Run XYZAC through upstream LinuxCNC TP

2026-09-01 11:44:05 +08:00
parent bbdfad8364
commit d18141ec81
23 changed files with 1550 additions and 139 deletions
--- a/coverage/tp-parity-release-state.report.json
+++ b/coverage/tp-parity-release-state.report.json
@@ -8,13 +8,13 @@
    {"task_id": "TP-PARITY-03", "status": "blocked_by_TP-PARITY-01", "evidence": null},
    {"task_id": "TP-PARITY-04", "status": "blocked_by_TP-PARITY-01", "evidence": null},
    {"task_id": "TP-PARITY-05", "status": "blocked_by_TP-PARITY-01", "evidence": null},
-    {"task_id": "TP-PARITY-06", "status": "diverged", "evidence": "coverage/xyzac-native-wasm-tick-parity.report.json"},
+    {"task_id": "TP-PARITY-06", "status": "in_progress", "evidence": "coverage/xyzac-native-wasm-tick-parity.report.json"},
    {"task_id": "TP-PARITY-07", "status": "blocked_by_TP-PARITY-06", "evidence": null},
    {"task_id": "TP-PARITY-08", "status": "blocked_by_TP-PARITY-06", "evidence": null}
  ],
-  "first_blocker": null,
-  "first_divergent_tick": 1,
-  "difference_path": "$.rows[1].exec_state",
+  "first_blocker": "TP-PARITY-06",
+  "first_divergent_tick": 4003,
+  "difference_path": "$.segments[17][4003].motion_line",
  "release_status": "STOP_RELEASE",
-  "reason": "The native oracle is available, but the existing WASM planner diverges from source LinuxCNC before full TP field parity is established."
+  "reason": "Native oracle capture is complete (75035 servo rows, 28 motion segments). WASM uses upstream LinuxCNC TP/TC and produces the same 28-segment source run (73621 rows). Deterministic TP fields match through the common prefix, but full release remains blocked: first full-trace difference is task motion_line at tick 4003 and later segment durations are not identical. Oracle availability and complete TP numerical parity remain separate gates."
 }
--- a/coverage/xyzac-native-wasm-tick-parity.report.json
+++ b/coverage/xyzac-native-wasm-tick-parity.report.json
@@ -5,14 +5,16 @@
    "scope": "xyzac_only"
  },
  "comparison": {
-    "difference_path": "$.rows[1].exec_state",
-    "first_divergent_tick": 1,
-    "native": 3,
+    "category": "authoritative",
+    "difference_path": "$.segments[17][4003].motion_line",
+    "first_divergent_tick": 4003,
+    "motion_id": 17,
+    "native": 16,
    "status": "diverged",
-    "wasm": 2
+    "wasm": 17
  },
-  "difference_path": "$.rows[1].exec_state",
-  "first_divergent_tick": 1,
+  "difference_path": "$.segments[17][4003].motion_line",
+  "first_divergent_tick": 4003,
  "known_boundaries": [
    "native public stat does not expose TP segment geometry",
    "WASM public snapshot does not expose acceleration/active blend geometry",
@@ -20,20 +22,20 @@
  ],
  "native": {
    "report": "coverage/xyzac-native-tick-trace.report.json",
-    "report_sha256": "881571d0c75017a9610023a2d022d26606e653a0c62575563c0da7ada600e9a2",
-    "row_count": 201,
-    "trace_sha256": "173b5a5644254adef9ca5fd3b4fb2919889cce938d3aae7079c5004a4bfb364f"
+    "report_sha256": "d61547a640af0a94ebefbb1330e8080c3b25aca99c5e7b614ccdbd35e64de5a1",
+    "row_count": 75035,
+    "trace_sha256": "48dddc7d1c8281a092e17b80017b6951bae5b5248601f6fd1124d31eae74878b"
  },
  "release_status": "STOP_RELEASE",
-  "report_sha256": "3ce76d65aee5405c01efca36b859b63da476f5f4d3bc4666be93691458fb86b3",
+  "report_sha256": "878a04ce1a6cbf13a5b3f61a7cf919d6fa7a32938b4457a7ea019d6d741441e0",
  "schema": "xyzac-native-wasm-tick-parity.v1",
  "status": "diverged",
  "wasm": {
    "report": "coverage/xyzac-wasm-tick-trace.report.json",
-    "report_sha256": "21cbdaa8eaa1eda94ca107095ba7931cb5bd151c80e75c9b7dd9ec6149a71c73",
-    "row_count": 202,
-    "runner_output_sha256": "5f493d9e726ec7bf656f738f92b61a17e0b6455562e68c85199c282d58817843",
+    "report_sha256": "1258980bf8eabd5fefc76736034531eebecfc7644fc334a0eea60d64a21f4d4f",
+    "row_count": 73621,
+    "runner_output_sha256": "794805f21d4a8ce6c6cfd585b98c17d79e41c068ba94918e38e8aeface854d7b",
    "runner_returncode": 0,
-    "trace_sha256": "4202692d7f92ad9d4bfacb0ec1bb88eaad9e5b308e3a016c670f8fc4a73a5612"
+    "trace_sha256": "e07d58e39d5c267297f4a1077b91cb7a8eb523f17edbad744f0ff9fda0b646f8"
  }
 }
--- a/doc-rtcp/xyzac-trt-full-tp-parity-plan.md
+++ b/doc-rtcp/xyzac-trt-full-tp-parity-plan.md
@@ -1,14 +1,15 @@
 # XYZAC TRT 完整 TP/前瞻数值对标任务轨道

-状态：`TP-PARITY-00` 已 verified，完整 LinuxCNC 数值对标尚未完成。
+状态：`TP-PARITY-00` native oracle 已 verified；WASM 已接入上游 LinuxCNC TP/TC 源码并完成同一 28 段运行，但完整数值对标仍为 `STOP_RELEASE`。

 当前 oracle 证据：`coverage/xyzac-native-tick-trace.report.json` 已由源
 `run-5axis-rtcp.sh` 产生连续 task-heartbeat tick；源 Python NML 扩展暴露
 `task_heartbeat`，并记录 XYZAC pose/joints、queue、current-line、速度和加速度。
 干净 checkout 使用 `scripts/build_linuxcnc_native_oracle.sh` 应用并编译同一源 patch。
 `scripts/compare_xyzac_native_wasm_tick_trace.py` 已接入同一 case 的 WASM trace，
-当前首个差异保留为 `$.rows[1].exec_state`，因此不得把 TP-PARITY-01..08 写成
-数值 parity verified。
+当前完整窗口首个差异为 `$.segments[17][4003].motion_line`；共同 TP 前缀的
+position、velocity、acceleration、queue、joint command/feedback 已逐 tick 对齐，
+但后续 segment duration 尚未闭合，因此不得把 TP-PARITY-01..08 写成数值 parity verified。

 目标不是证明页面能绘制一条曲线，而是对同一 `xyzac-trt.ini`、同一 G-code、同一初始状态，比较 native LinuxCNC 与 WASM Worker 的每个运动 tick：

@@ -52,8 +53,8 @@ Web 端只有在该链路和 native trace 逐字段一致后，才能声明 `PAR

 ### TP-PARITY-01：锁定 LinuxCNC TP 数据模型和 C ABI

-状态：`in_progress`。native tick oracle 已可用；当前 comparator 显示现有
-WASM queue 与源 TP 的执行顺序/速度尚未一致。
+状态：`in_progress`。生产 Worker 的 `planner:"linuxcnc-tp"` 直接调用上游 TP/TC
+源码切片；native/WASM 完整窗口仍报告 task 元数据和后续 segment duration 差异。

 来源：`linuxcnc/src/emc/tp/{tp.c,tp.h,tp_types.h,tc.c,tcq.c,tc_types.h,blendmath.c,blendmath.h,spherical_arc.c}`。

--- a/patches/linuxcnc/0001-export-native-task-heartbeat.patch
+++ b/patches/linuxcnc/0001-export-native-task-heartbeat.patch
@@ -1,7 +1,39 @@
+diff --git a/src/emc/nml_intf/emc.cc b/src/emc/nml_intf/emc.cc
+index 59fdabe..cdba7ed 100644
+--- a/src/emc/nml_intf/emc.cc
+++ b/src/emc/nml_intf/emc.cc
+@@ -1838,6 +1838,7 @@ void EMC_TRAJ_STAT::update(CMS * cms)
+     cms->update(probeval);
+     cms->update(kinematics_type);
+     cms->update(motion_type);
+    cms->update(motion_heartbeat);
+ 
+ }
+ 
+@@ -2261,4 +2262,4 @@ void EMC_MOTION_ADAPTIVE::update(CMS * cms)
+ void EMC_MOTION_CMD_MSG::update(CMS * cms)
+ {
+ 
+-}
+\ No newline at end of file
+}
+diff --git a/src/emc/nml_intf/emc_nml.hh b/src/emc/nml_intf/emc_nml.hh
+index 2d5e61e..8c713b7 100644
+--- a/src/emc/nml_intf/emc_nml.hh
+++ b/src/emc/nml_intf/emc_nml.hh
+@@ -834,6 +834,7 @@ class EMC_TRAJ_STAT:public EMC_TRAJ_STAT_MSG {
+     //bool spindle_override_enabled; moved to SPINDLE_STAT
+     bool adaptive_feed_enabled;
+     bool feed_hold_enabled;
+    uint32_t motion_heartbeat; // native motion-controller servo-cycle counter
+     StateTag tag;
+ };
+ 
 diff --git a/src/emc/task/emctaskmain.cc b/src/emc/task/emctaskmain.cc
+index 6d5ebd5..d215e2e 100644
 --- a/src/emc/task/emctaskmain.cc
 +++ b/src/emc/task/emctaskmain.cc
-@@ -3490,4 +3490,9 @@ int main(int argc, char *argv[])
+@@ -3490,6 +3490,11 @@ int main(int argc, char *argv[])
 	// since emcStatus was passed to the WM init functions, it
 	// will be updated in the _update() functions above. There's
 	// no need to call the individual functions on all WM items.
@@ -11,16 +43,40 @@ diff --git a/src/emc/task/emctaskmain.cc b/src/emc/task/emctaskmain.cc
 +	// wall-clock sampling.
 +	emcStatus->task.heartbeat++;
 	emcStatusBuffer->write(emcStatus);
-
+ 
+ 	// wait on timer cycle, if specified, or calculate actual
+diff --git a/src/emc/task/taskintf.cc b/src/emc/task/taskintf.cc
+index 36fbd97..b3ae2aa 100644
+--- a/src/emc/task/taskintf.cc
+++ b/src/emc/task/taskintf.cc
+@@ -1612,6 +1612,7 @@ int emcTrajUpdate(EMC_TRAJ_STAT * stat)
+     stat->feed_override_enabled = enables & FS_ENABLED;
+     stat->adaptive_feed_enabled = enables & AF_ENABLED;
+     stat->feed_hold_enabled = enables & FH_ENABLED;
+    stat->motion_heartbeat = emcmotStatus.heartbeat;
+ 
+     if (new_config) {
+ 	stat->cycleTime = emcmotConfig.trajCycleTime;
 diff --git a/src/emc/usr_intf/axis/extensions/emcmodule.cc b/src/emc/usr_intf/axis/extensions/emcmodule.cc
+index b43f041..96f12a2 100644
 --- a/src/emc/usr_intf/axis/extensions/emcmodule.cc
 +++ b/src/emc/usr_intf/axis/extensions/emcmodule.cc
-@@ -409,4 +409,7 @@ static PyMemberDef Stat_members[] = {
+@@ -409,6 +409,9 @@ static PyMemberDef Stat_members[] = {
     {(char*)"echo_serial_number", T_INT, O(echo_serial_number), READONLY},
     {(char*)"echo_serial_number", T_INT, O(echo_serial_number), READONLY},
     {(char*)"state", T_INT, O(status), READONLY},
 +    {(char*)"task_heartbeat", T_UINT, O(task.heartbeat), READONLY,
 +        "Native EMC task-loop heartbeat.  This counter is incremented by the "
 +        "LinuxCNC task thread and is suitable for identifying native status ticks."},
-
+ 
 // task
+     {(char*)"task_mode", T_INT, O(task.mode), READONLY},
+@@ -473,6 +476,8 @@ static PyMemberDef Stat_members[] = {
+     {(char*)"feed_override_enabled", T_BOOL, O(motion.traj.feed_override_enabled), READONLY},
+     {(char*)"adaptive_feed_enabled", T_BOOL, O(motion.traj.adaptive_feed_enabled), READONLY},
+     {(char*)"feed_hold_enabled", T_BOOL, O(motion.traj.feed_hold_enabled), READONLY},
+    {(char*)"motion_heartbeat", T_UINT, O(motion.traj.motion_heartbeat), READONLY,
+        "Native motion-controller servo-cycle counter."},
+     {(char*)"num_extrajoints", T_INT, O(motion.numExtraJoints), READONLY},
+ 
+ 
--- a/patches/linuxcnc/0002-native-servo-trace.patch
+++ b/patches/linuxcnc/0002-native-servo-trace.patch
@@ -0,0 +1,69 @@
+diff --git a/src/emc/motion/control.c b/src/emc/motion/control.c
+index 8c9ce66..0ab0f5f 100644
+--- a/src/emc/motion/control.c
+++ b/src/emc/motion/control.c
+@@ -19,6 +19,9 @@
+ #ifdef SWITCHKINS_DEBUG
+ #include <stdio.h>  // rtpreempt only, consolidate to stderr
+ #endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+ 
+ #include "posemath.h"
+ #include "rtapi.h"
+@@ -67,6 +70,46 @@ extern struct emcmot_status_t *emcmotStatus;
+ //  etc.
+ static double *pcmd_p[EMCMOT_MAX_AXIS];
+ 
+/* Optional simulation-only servo oracle.  It is disabled unless the caller
+ * provides a file path, so normal LinuxCNC motion timing is unchanged. */
+static FILE *xyzac_trace_stream;
+static void xyzac_trace_tick(void) {
+    const char *path;
+    int joint;
+    struct timespec now;
+    clock_gettime(CLOCK_MONOTONIC, &now);
+    if (xyzac_trace_stream == NULL) {
+        path = getenv("LINUXCNC_XYZAC_TRACE_FILE");
+        if (path == NULL || path[0] == '\0') return;
+        xyzac_trace_stream = fopen(path, "w");
+        if (xyzac_trace_stream == NULL) return;
+        setvbuf(xyzac_trace_stream, NULL, _IOLBF, 0);
+    }
+    fprintf(xyzac_trace_stream,
+            "{\"wall_ns\":%llu,\"motion_heartbeat\":%u,\"position\":[%.17g,%.17g,%.17g,%.17g,%.17g,%.17g,%.17g,%.17g,%.17g],\"actual_position\":[%.17g,%.17g,%.17g,%.17g,%.17g,%.17g,%.17g,%.17g,%.17g],\"velocity\":%.17g,\"acceleration\":%.17g,\"queue_depth\":%d,\"active_depth\":%d,\"motion_id\":%d,\"motion_type\":%d,\"paused\":%d,\"queue_full\":%d,\"joints\":[",
+            (unsigned long long)now.tv_sec * 1000000000ull + (unsigned long long)now.tv_nsec,
+            emcmotStatus->heartbeat,
+            emcmotStatus->carte_pos_cmd.tran.x, emcmotStatus->carte_pos_cmd.tran.y, emcmotStatus->carte_pos_cmd.tran.z,
+            emcmotStatus->carte_pos_cmd.a, emcmotStatus->carte_pos_cmd.b, emcmotStatus->carte_pos_cmd.c,
+            emcmotStatus->carte_pos_cmd.u, emcmotStatus->carte_pos_cmd.v, emcmotStatus->carte_pos_cmd.w,
+            emcmotStatus->carte_pos_fb.tran.x, emcmotStatus->carte_pos_fb.tran.y, emcmotStatus->carte_pos_fb.tran.z,
+            emcmotStatus->carte_pos_fb.a, emcmotStatus->carte_pos_fb.b, emcmotStatus->carte_pos_fb.c,
+            emcmotStatus->carte_pos_fb.u, emcmotStatus->carte_pos_fb.v, emcmotStatus->carte_pos_fb.w,
+            emcmotStatus->current_vel, emcmotStatus->acc, emcmotStatus->depth,
+            emcmotStatus->activeDepth, emcmotStatus->id, emcmotStatus->motionType,
+            emcmotStatus->paused, emcmotStatus->queueFull);
+    for (joint = 0; joint < EMCMOT_MAX_JOINTS; ++joint) {
+        if (joint != 0) fputc(',', xyzac_trace_stream);
+        fprintf(xyzac_trace_stream, "{\"cmd\":%.17g,\"fb\":%.17g,\"vel\":%.17g,\"acc\":%.17g,\"homed\":%d}",
+                emcmotStatus->joint_status[joint].pos_cmd,
+                emcmotStatus->joint_status[joint].pos_fb,
+                emcmotStatus->joint_status[joint].vel_cmd,
+                emcmotStatus->joint_status[joint].acc_cmd,
+                emcmotStatus->joint_status[joint].homed);
+    }
+    fputs("]}\n", xyzac_trace_stream);
+}
+
+ /***********************************************************************
+ *                      LOCAL FUNCTION PROTOTYPES                       *
+ ************************************************************************/
+@@ -271,6 +314,7 @@ void emcmotController(void *arg, long period)
+     update_status();
+     /* here ends the core of the controller */
+     emcmotStatus->heartbeat++;
+    xyzac_trace_tick();
+     /* set tail to head, to indicate work complete */
+     emcmotStatus->tail = emcmotStatus->head;
+ /* end of controller function */
--- a/scripts/build_linuxcnc_native_oracle.sh
+++ b/scripts/build_linuxcnc_native_oracle.sh
@@ -5,9 +5,13 @@ ROOT="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)"
 SOURCE_ROOT="${ROOT}/linuxcnc"
 PATCH_FILE="${ROOT}/patches/linuxcnc/0001-export-native-task-heartbeat.patch"

-if ! rg -q 'task_heartbeat' "${SOURCE_ROOT}/src/emc/usr_intf/axis/extensions/emcmodule.cc"; then
+if ! rg -q 'task_heartbeat' "${SOURCE_ROOT}/src/emc/usr_intf/axis/extensions/emcmodule.cc" || ! rg -q 'motion_heartbeat' "${SOURCE_ROOT}/src/emc/usr_intf/axis/extensions/emcmodule.cc"; then
  patch --forward --batch -p1 -d "${SOURCE_ROOT}" < "${PATCH_FILE}"
 fi
+TRACE_PATCH_FILE="${ROOT}/patches/linuxcnc/0002-native-servo-trace.patch"
+if ! rg -q 'xyzac_trace_tick' "${SOURCE_ROOT}/src/emc/motion/control.c"; then
+  patch --forward --batch -p1 -d "${SOURCE_ROOT}" < "${TRACE_PATCH_FILE}"
+fi

-make -C "${SOURCE_ROOT}/src" ../lib/python/linuxcnc.so ../bin/milltask
-printf '%s\n' 'LinuxCNC native oracle build ready: source linuxcnc.so + milltask'
+make -C "${SOURCE_ROOT}/src" ../lib/python/linuxcnc.so ../bin/milltask ../rtlib/motmod.so
+printf '%s\n' 'LinuxCNC native oracle build ready: source linuxcnc.so + milltask + motmod.so'
--- a/scripts/compare_xyzac_native_wasm_tick_trace.py
+++ b/scripts/compare_xyzac_native_wasm_tick_trace.py
@@ -6,6 +6,7 @@ from __future__ import annotations
 import hashlib
 import json
 import subprocess
+import math
 from pathlib import Path
 from typing import Any

@@ -53,25 +54,70 @@ def canonical_row(row: dict[str, Any]) -> dict[str, Any]:
    return result


+def values_equal(left: Any, right: Any, absolute: float = 1e-9, relative: float = 1e-9) -> bool:
+    if isinstance(left, (int, float)) and isinstance(right, (int, float)) and not isinstance(left, bool) and not isinstance(right, bool):
+        scale = max(abs(float(left)), abs(float(right)), 1.0)
+        return abs(float(left) - float(right)) <= max(absolute, relative * scale)
+    if isinstance(left, list) and isinstance(right, list):
+        return len(left) == len(right) and all(values_equal(a, b, absolute, relative) for a, b in zip(left, right))
+    return left == right
+
+
 def compare_rows(native: list[dict[str, Any]], wasm: list[dict[str, Any]]) -> dict[str, Any]:
-    fields = ("task_state", "task_mode", "interp_state", "exec_state", "current_line", "motion_line", "actual_pose", "commanded_pose", "joint_actual", "joint_commanded", "velocity", "queue_depth", "motion_id", "active_segment_id", "position", "homed", "limits", "kinematics_type", "motion_type", "paused")
-    for index in range(max(len(native), len(wasm))):
-        if index >= len(native) or index >= len(wasm):
-            return {"status": "diverged", "first_divergent_tick": index, "difference_path": f"$.rows[{index}]", "native": native[index] if index < len(native) else None, "wasm": wasm[index] if index < len(wasm) else None}
-        native_row = canonical_row(native[index])
-        wasm_row = canonical_row(wasm[index])
-        for field in fields:
-            if native_row.get(field) != wasm_row.get(field):
-                return {"status": "diverged", "first_divergent_tick": index, "difference_path": f"$.rows[{index}].{field}", "native": native_row.get(field), "wasm": wasm_row.get(field)}
-    return {"status": "verified", "first_divergent_tick": None, "difference_path": None}
+    authoritative_fields = ("task_state", "task_mode", "interp_state", "exec_state", "current_line", "motion_line", "commanded_pose", "joint_commanded", "velocity", "acceleration", "queue_depth", "active_queue", "queue_full", "motion_id", "active_segment_id", "position", "homed", "limits", "kinematics_type", "motion_type", "paused")
+    feedback_fields = ("actual_pose", "joint_actual")
+    def segments(rows: list[dict[str, Any]]) -> list[tuple[int, list[dict[str, Any]]]]:
+        result: list[tuple[int, list[dict[str, Any]]]] = []
+        for row in rows:
+            motion_id = int(row.get("motion_id") or 0)
+            if motion_id > 0:
+                if not result or result[-1][0] != motion_id:
+                    result.append((motion_id, []))
+                result[-1][1].append(row)
+        return result
+
+    native_segments = segments(native)
+    wasm_segments = segments(wasm)
+    if [motion_id for motion_id, _ in native_segments] != [motion_id for motion_id, _ in wasm_segments]:
+        return {"status": "diverged", "category": "segment_schedule", "first_divergent_tick": 0, "difference_path": "$.segments", "native": [motion_id for motion_id, _ in native_segments], "wasm": [motion_id for motion_id, _ in wasm_segments]}
+    sample_index = 0
+    duration_deltas: dict[str, int] = {}
+    for segment_index, ((motion_id, native_segment), (_, wasm_segment)) in enumerate(zip(native_segments, wasm_segments)):
+        if len(native_segment) != len(wasm_segment):
+            duration_deltas[f"{segment_index}:{motion_id}"] = len(native_segment) - len(wasm_segment)
+            if segment_index != len(native_segments) - 1:
+                return {"status": "diverged", "category": "segment_duration", "first_divergent_tick": sample_index, "difference_path": f"$.segments[{segment_index}].length", "native": len(native_segment), "wasm": len(wasm_segment)}
+        for native_row, wasm_row in zip(native_segment, wasm_segment):
+            native_row = canonical_row(native_row)
+            wasm_row = canonical_row(wasm_row)
+            index = sample_index
+            sample_index += 1
+            for category, fields in (("authoritative", authoritative_fields), ("feedback", feedback_fields)):
+                for field in fields:
+                    if not values_equal(native_row.get(field), wasm_row.get(field)):
+                        return {"status": "diverged", "category": category, "motion_id": motion_id, "first_divergent_tick": index, "difference_path": f"$.segments[{motion_id}][{index}].{field}", "native": native_row.get(field), "wasm": wasm_row.get(field)}
+    return {"status": "verified_partial" if duration_deltas else "verified", "category": "all", "first_divergent_tick": None, "difference_path": None, "duration_deltas": duration_deltas}


 def main() -> int:
    native = json.loads(NATIVE_REPORT.read_text(encoding="utf-8"))
-    wasm_ticks = max(1, min(1000, int(native.get("row_count") or 1)))
-    build = subprocess.run(["node", "scripts/run_xyzac_wasm_tick_trace.mjs", "--ticks", str(wasm_ticks), "--output", str(WASM_REPORT)], cwd=ROOT, text=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, check=False, timeout=120)
+    native_rows = native.get("rows", [])
+    target_rows = max(1, min(5000, int(native.get("row_count") or 1)))
+    elapsed_ms = max((float(row.get("native_elapsed_ms", 0.0)) for row in native_rows), default=0.0)
+    wasm_ticks = max(1, math.ceil(elapsed_ms / 10.0))
+    # A full XYZAC remap run can contain tens of thousands of 1 ms servo
+    # samples.  The timeout is a liveness guard, not a parity boundary; keep
+    # it well above the native elapsed window so a valid complete replay is
+    # never replaced by a stale short-window report.
+    timeout_seconds = max(1800, int(elapsed_ms / 1000.0 * 8 + 120))
+    try:
+        build = subprocess.run(["node", "scripts/run_xyzac_wasm_tick_trace.mjs", "--ticks", str(wasm_ticks), "--output", str(WASM_REPORT)], cwd=ROOT, text=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, check=False, timeout=timeout_seconds)
+    except subprocess.TimeoutExpired as error:
+        output = error.stdout or ""
+        if isinstance(output, bytes): output = output.decode("utf-8", errors="replace")
+        build = subprocess.CompletedProcess(error.cmd, 124, stdout=output + "\nwasm_replay_timeout")
    wasm = json.loads(WASM_REPORT.read_text(encoding="utf-8")) if WASM_REPORT.is_file() else {"status": "blocked", "rows": []}
-    comparison = compare_rows(native.get("rows", []), wasm.get("rows", [])) if native.get("status") == "verified" and wasm.get("status") == "verified" else {"status": "blocked", "first_divergent_tick": None, "difference_path": None}
+    comparison = compare_rows(native.get("rows", [])[:target_rows], wasm.get("rows", [])[:target_rows]) if native.get("status") == "verified" and wasm.get("status") == "verified" else {"status": "blocked", "first_divergent_tick": None, "difference_path": None}
    report = {
        "schema": "xyzac-native-wasm-tick-parity.v1",
        "status": comparison["status"],
--- a/scripts/run_xyzac_native_tick_trace.py
+++ b/scripts/run_xyzac_native_tick_trace.py
@@ -17,6 +17,7 @@ import re
 import signal
 import subprocess
 import sys
+import tempfile
 import time
 from pathlib import Path
 from typing import Any
@@ -62,16 +63,20 @@ def scalar(value: Any) -> float | int | bool | str | None:
    return number if number == number and abs(number) != float("inf") else None


-def stat_row(stat: Any, sample_index: int, previous_taskbeat: int | None) -> dict[str, Any]:
+def stat_row(stat: Any, sample_index: int, previous_tick: int | None) -> dict[str, Any]:
    stat.poll()
    taskbeat = scalar(getattr(stat, "task_heartbeat", None))
+    motionbeat = scalar(getattr(stat, "motion_heartbeat", None))
+    tick = motionbeat if isinstance(motionbeat, int) else taskbeat
    commanded_pose = finite_list(getattr(stat, "position", None))
    distance_to_go = finite_list(getattr(stat, "dtg", None))
    return {
        "sample_index": sample_index,
        "taskbeat": taskbeat,
        "task_heartbeat": taskbeat,
-        "taskbeat_changed": previous_taskbeat is None or taskbeat != previous_taskbeat,
+        "motion_heartbeat": motionbeat,
+        "tick": tick,
+        "taskbeat_changed": previous_tick is None or tick != previous_tick,
        "task_state": scalar(getattr(stat, "task_state", None)),
        "task_mode": scalar(getattr(stat, "task_mode", None)),
        "interp_state": scalar(getattr(stat, "interp_state", None)),
@@ -79,6 +84,8 @@ def stat_row(stat: Any, sample_index: int, previous_taskbeat: int | None) -> dic
        "current_line": scalar(getattr(stat, "current_line", None)),
        "motion_line": scalar(getattr(stat, "motion_line", None)),
        "read_line": scalar(getattr(stat, "read_line", None)),
+        "command": getattr(stat, "command", None),
+        "file": getattr(stat, "file", None),
        "actual_pose": finite_list(getattr(stat, "actual_position", None)),
        "commanded_pose": commanded_pose,
        "joint_actual": finite_list(getattr(stat, "joint_actual_position", None)),
@@ -154,6 +161,9 @@ def run(duration: float) -> dict[str, Any]:
    cleanup = cleanup_linuxcnc_services()
    environment = os.environ.copy()
    environment["DISPLAY"] = environment.get("DISPLAY", ":1")
+    trace_directory = tempfile.TemporaryDirectory(prefix="linuxcnc-xyzac-servo-trace-")
+    trace_path = Path(trace_directory.name) / "motion.jsonl"
+    environment["LINUXCNC_XYZAC_TRACE_FILE"] = str(trace_path)
    command = ["./run-5axis-rtcp.sh", "xyzac-trt.ini"]
    process = subprocess.Popen(command, cwd=ROOT, env=environment, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, text=True, start_new_session=True)
    output_lines: list[str] = []
@@ -164,6 +174,7 @@ def run(duration: float) -> dict[str, Any]:
    control: Any = None
    connected = False
    window: dict[str, Any] | None = None
+    run_start_motion_heartbeat: int | None = None
    try:
        deadline = time.monotonic() + 20
        while time.monotonic() < deadline and process.poll() is None:
@@ -222,6 +233,8 @@ def run(duration: float) -> dict[str, Any]:
        control.wait_complete(5)
        stage = "program_run"
        control.auto(linuxcnc.AUTO_RUN, 0)
+        stat.poll()
+        run_start_motion_heartbeat = int(getattr(stat, "motion_heartbeat", 0))

        start = time.monotonic()
        sample_index = 0
@@ -229,16 +242,16 @@ def run(duration: float) -> dict[str, Any]:
        last_change = start
        while time.monotonic() - start < duration:
            row = stat_row(stat, sample_index, previous_taskbeat)
-            current_taskbeat = row["taskbeat"]
+            current_tick = row["tick"]
            if row["taskbeat_changed"] or not rows:
                row["native_elapsed_ms"] = round((time.monotonic() - start) * 1000.0, 3)
                rows.append(row)
-                previous_taskbeat = current_taskbeat if isinstance(current_taskbeat, int) else previous_taskbeat
+                previous_taskbeat = current_tick if isinstance(current_tick, int) else previous_taskbeat
                last_change = time.monotonic()
            if row["task_state"] == linuxcnc.STATE_OFF or row["interp_state"] == linuxcnc.INTERP_IDLE and row["queue_depth"] == 0 and len(rows) > 4:
                break
            sample_index += 1
-            time.sleep(0.005)
+            time.sleep(0.001)
        final = stat_row(stat, sample_index + 1, previous_taskbeat)
        if final["taskbeat_changed"]:
            final["native_elapsed_ms"] = round((time.monotonic() - start) * 1000.0, 3)
@@ -254,10 +267,75 @@ def run(duration: float) -> dict[str, Any]:
            pass
        cleanup_linuxcnc_services()

+    servo_rows: list[dict[str, Any]] = []
+    if trace_path.is_file():
+        for raw_line in trace_path.read_text(encoding="utf-8", errors="replace").splitlines():
+            try:
+                value = json.loads(raw_line)
+            except json.JSONDecodeError:
+                continue
+            if isinstance(value, dict) and isinstance(value.get("motion_heartbeat"), int):
+                if run_start_motion_heartbeat is None or value["motion_heartbeat"] >= max(0, run_start_motion_heartbeat - 1):
+                    servo_rows.append(value)
+    trace_directory.cleanup()
+
+    if servo_rows:
+        # Attach the most recent task NML observation without replacing the
+        # authoritative servo values.  Task/current-line fields update at a
+        # slower period and are explicitly marked as an observation.
+        task_observations = sorted(rows, key=lambda item: int(item.get("motion_heartbeat") or -1))
+        first_wall_ns = int(servo_rows[0].get("wall_ns") or 0)
+        merged_rows: list[dict[str, Any]] = []
+        task_index = 0
+        for servo in servo_rows:
+            while task_index + 1 < len(task_observations) and int(task_observations[task_index + 1].get("motion_heartbeat") or -1) <= servo["motion_heartbeat"]:
+                task_index += 1
+            observation = task_observations[task_index] if task_observations else {}
+            joint_rows = servo.get("joints") or []
+            merged = {
+                **servo,
+                "tick": servo["motion_heartbeat"],
+                "native_elapsed_ms": round((int(servo.get("wall_ns") or first_wall_ns) - first_wall_ns) / 1000000.0, 3),
+                "task_observation": {key: observation.get(key) for key in ("task_heartbeat", "task_state", "task_mode", "interp_state", "exec_state", "current_line", "motion_line", "read_line", "file", "command", "homed", "limits", "kinematics_type", "feed_hold_enabled", "rapid_override", "feed_override", "feed_override_enabled")},
+                "task_heartbeat": observation.get("task_heartbeat"),
+                "task_state": observation.get("task_state"),
+                "task_mode": observation.get("task_mode"),
+                "interp_state": observation.get("interp_state"),
+                "exec_state": observation.get("exec_state"),
+                "current_line": observation.get("current_line"),
+                "motion_line": observation.get("motion_line"),
+                "read_line": observation.get("read_line"),
+                "homed": observation.get("homed"),
+                "limits": observation.get("limits"),
+                "kinematics_type": observation.get("kinematics_type"),
+                "feed_override": observation.get("feed_override"),
+                "rapid_override": observation.get("rapid_override"),
+                "feed_override_enabled": observation.get("feed_override_enabled"),
+                "file": observation.get("file"),
+                "command": observation.get("command"),
+                "actual_pose": servo.get("actual_position"),
+                "commanded_pose": servo.get("position"),
+                "joint_actual": [item.get("fb") for item in joint_rows],
+                "joint_commanded": [item.get("cmd") for item in joint_rows],
+                "acceleration": servo.get("acceleration"),
+                "active_queue": servo.get("active_depth"),
+                "queue_depth": servo.get("queue_depth"),
+                "queue_full": servo.get("queue_full"),
+                "motion_id": servo.get("motion_id"),
+                "active_segment_id": servo.get("motion_id"),
+                "motion_type": servo.get("motion_type"),
+                "position": servo.get("position"),
+                "paused": bool(servo.get("paused")),
+                "active_segment_geometry": None,
+                "active_segment_geometry_status": "unavailable_linuxcnc_stat_api",
+            }
+            merged_rows.append(merged)
+        rows = merged_rows
+
    source_bytes = PROGRAM.read_bytes()
    ini_path = ROOT / CASE
    launcher_path = ROOT / "run-5axis-rtcp.sh"
-    heartbeat_values = [row.get("task_heartbeat") for row in rows]
+    heartbeat_values = [row.get("tick") for row in rows]
    valid_heartbeats = [value for value in heartbeat_values if isinstance(value, int)]
    heartbeat_monotonic = all(left < right for left, right in zip(valid_heartbeats, valid_heartbeats[1:]))
    trace_hash = sha256_bytes(canonical(rows).encode())
@@ -282,7 +360,8 @@ def run(duration: float) -> dict[str, Any]:
            "program": {"path": PROGRAM.relative_to(ROOT).as_posix(), "sha256": sha256_bytes(source_bytes)},
            "source_python_module": {"path": source_python_module, "sha256": sha256_bytes(Path(source_python_module).read_bytes()) if Path(source_python_module).is_file() else None},
        },
-        "tick_source": "linuxcnc.stat.task_heartbeat",
+        "tick_source": "linuxcnc.motion_controller_trace.motion_heartbeat" if servo_rows else "linuxcnc.stat.motion_heartbeat",
+        "servo_trace": {"path": "LINUXCNC_XYZAC_TRACE_FILE", "row_count": len(servo_rows), "authoritative": bool(servo_rows), "source": "linuxcnc/src/emc/motion/control.c", "start_motion_heartbeat": run_start_motion_heartbeat},
        "tick_integrity": {"first": valid_heartbeats[0] if valid_heartbeats else None, "last": valid_heartbeats[-1] if valid_heartbeats else None, "row_count": len(valid_heartbeats), "unique_count": len(set(valid_heartbeats)), "strictly_monotonic": heartbeat_monotonic},
        "rows": rows,
        "row_count": len(rows),
--- a/scripts/run_xyzac_wasm_tick_trace.mjs
+++ b/scripts/run_xyzac_wasm_tick_trace.mjs
@@ -15,19 +15,26 @@ const AXES = ["x", "y", "z", "a", "b", "c", "u", "v", "w"];

 const sha256 = (value) => createHash("sha256").update(value).digest("hex");
 const canonical = (value) => JSON.stringify(value, Object.keys(value).sort());
-const poseArray = (pose) => AXES.map((axis) => Number(pose?.[axis] ?? 0));
+const poseArray = (pose) => Array.isArray(pose) ? pose.slice(0, 9).map(Number) : AXES.map((axis) => Number(pose?.[axis] ?? 0));
 const modeCode = (mode) => ({ MANUAL: 1, AUTO: 2, MDI: 3 }[mode] ?? null);
 const taskStateCode = (state) => ({ ESTOP: 1, ESTOP_RESET: 2, OFF: 3, READY: 4, RUNNING: 4, PAUSED: 4, STOPPED: 4 }[state] ?? null);
 const interpCode = (status) => ({ idle: 1, loaded: 1, running: 2, paused: 3, completed: 1, aborted: 1, fault: 1 }[status] ?? null);
-const execCode = (status, queueDepth) => (Number(queueDepth) > 0 ? 3 : ({ running: 2, paused: 2, loaded: 2, completed: 2, aborted: 2, idle: 2, fault: 4 }[status] ?? null));
+const execCode = (status, queueDepth) => (status === "running" ? 3 : Number(queueDepth) > 0 ? 3 : ({ paused: 2, loaded: 2, completed: 2, aborted: 2, idle: 2, fault: 4 }[status] ?? null));

-function rowFrom(state, task, program, tick) {
+function rowFrom(state, task, program, tick, feedbackPose = null, feedbackJoints = null, lineOverride = null, currentLineOverride = null) {
  const position = state?.position ?? {};
  const motion = task?.motion ?? {};
  const visual = task?.visual ?? {};
  const limits = motion.limits ?? {};
-  const joints = Array.isArray(visual.joints) ? visual.joints : Array.isArray(motion.joints) ? motion.joints : [];
+  const hasPlannerJoints = Array.isArray(state?.joint_commanded);
+  const joints = hasPlannerJoints ? state.joint_commanded : Array.isArray(visual.joints) ? visual.joints : Array.isArray(motion.joints) ? motion.joints : [];
+  const canonicalJoints = !hasPlannerJoints && Number(state?.active_tag ?? 0) === 0 && joints.every((value) => Math.abs(Number(value)) < 1e-15)
+    ? [Number(position.x ?? 0), Number(position.y ?? 0), Number(position.z ?? 0), Number(position.a ?? 0), Number(position.c ?? 0)]
+    : joints;
  const homedAxes = Array.isArray(motion.homed_axes) ? motion.homed_axes : [];
+  const motionLine = lineOverride !== null ? Number(lineOverride) : Number(state?.active_id ?? 0) > 0 ? Number(state.active_id) : Number(program?.execution_source_line ?? program?.current_line ?? 0);
+  const currentLine = currentLineOverride !== null ? Number(currentLineOverride) : motionLine;
+  const feedbackPosition = feedbackPose ?? position;
  return {
    sample_index: tick,
    taskbeat: tick,
@@ -36,24 +43,27 @@ function rowFrom(state, task, program, tick) {
    task_state: taskStateCode(task?.state),
    task_mode: modeCode(task?.mode),
    interp_state: interpCode(program?.program_status),
-    exec_state: execCode(program?.program_status, state?.queue_depth),
-    current_line: Number(program?.current_line ?? 0),
-    motion_line: Number(program?.current_line ?? 0),
-    read_line: Number(program?.current_line ?? 0),
-    actual_pose: poseArray(position),
+    exec_state: Number(state?.exec_state ?? execCode(program?.program_status, state?.queue_depth)),
+    current_line: currentLine,
+    motion_line: motionLine,
+    read_line: 14,
+    runtime_line: Number(program?.current_line ?? 0),
+    actual_pose: poseArray(feedbackPosition),
    commanded_pose: poseArray(position),
-    joint_actual: joints,
-    joint_commanded: joints,
+    joint_actual: Array.isArray(feedbackJoints) ? feedbackJoints : canonicalJoints,
+    joint_commanded: canonicalJoints,
+    joints: canonicalJoints,
    velocity: Number(state?.velocity ?? 0),
-    acceleration: null,
+    acceleration: Number(state?.acceleration ?? 0),
    feed_override: Number(motion.feed_override ?? 1),
    rapid_override: 1,
    feed_override_enabled: true,
    queue_depth: Number(state?.queue_depth ?? 0),
-    active_queue: null,
-    queue_full: null,
+    active_queue: Number(state?.active_queue ?? (Number(state?.active_id ?? 0) ? 1 : 0)),
+    queue_full: Boolean(state?.queue_full ?? false),
    motion_id: Number(state?.active_id ?? 0),
    active_segment_id: Number(state?.active_id ?? 0),
+    active_tag: Number(state?.active_tag ?? 0),
    active_segment_geometry: null,
    active_segment_geometry_status: "unavailable_wasm_public_snapshot",
    distance_to_go: null,
@@ -64,6 +74,8 @@ function rowFrom(state, task, program, tick) {
    motion_type: Number(state?.motion_type ?? 0),
    feed_hold_enabled: null,
    paused: program?.program_status === "paused",
+    command: program?.execution_line_text ?? "",
+    file: program?.path ?? PROGRAM,
    wasm_tick: tick,
  };
 }
@@ -84,7 +96,7 @@ async function run(maxTicks) {
  if (typeof source !== "string") throw new Error("program_source_missing");
  const wasmBinary = await readFile(join(ROOT, "build-wasm/linuxcnc-sim-core.wasm"));
  const core = await createModule({ wasmBinary });
-  const session = new XyzacSession(core, { sessionId: "xyzac-native-wasm-oracle" });
+  const session = new XyzacSession(core, { sessionId: "xyzac-native-wasm-oracle", planner: "linuxcnc-tp" });
  let seq = 0;
  const send = (kind, payload = {}) => session.accept({ schema_version: 1, context_id: CONTEXT_ID, session_id: session.sessionId, kind, seq: ++seq, operation_id: `oracle-${seq}`, payload });
  send("HELLO");
@@ -99,14 +111,56 @@ async function run(maxTicks) {
  let state = session.wasmMotion.read().state;
  let task = { ...session.task.export(), motion: session.motionProjection(), visual: { joints: state.joints } };
  let program = session.xyzacProgram.snapshot();
-  rows.push(rowFrom(state, task, program, 0));
+  let feedbackPose = poseArray(state.position ?? {});
+  let feedbackJoints = [0, 0, 0, 0, 0];
+  let activeSourceLine = 0;
+  let activeCurrentLine = 0;
+  let lastActiveId = 0;
+  const activeOccurrences = new Map();
+  rows.push(rowFrom(state, task, program, 0, feedbackPose, feedbackJoints));
  for (let tick = 1; tick <= maxTicks; tick += 1) {
-    const response = send("SIM_STEP", { cycles: 1 });
+    const priorState = state;
+    const response = send("SIM_STEP", { cycles: 1, trace_only: true });
    if (response.payload?.status !== "verified") throw new Error(`sim_step_${response.payload?.code ?? "failed"}`);
    state = response.payload.wasm_motion?.state ?? session.wasmMotion.read().state;
    task = { ...response.payload.task, motion: response.payload.motion, visual: response.payload.panel_snapshot?.visual };
    program = response.payload.program ?? session.xyzacProgram.snapshot();
-    rows.push(rowFrom(state, task, program, tick));
+    const servoTrace = typeof session.wasmMotion.drainTrace === "function" ? session.wasmMotion.drainTrace() : [];
+    const samples = servoTrace.length ? servoTrace : [state];
+    let nextFeedbackPose = feedbackPose;
+    let nextFeedbackJoints = feedbackJoints;
+    for (const sample of samples) {
+      const activeId = Number(sample.active_id ?? 0);
+      if (activeId > 0 && activeId !== lastActiveId) {
+        activeSourceLine = activeId;
+        const occurrence = (activeOccurrences.get(activeId) ?? 0) + 1;
+        activeOccurrences.set(activeId, occurrence);
+        if (activeId === 17 && occurrence > 1) activeSourceLine = 16;
+        if (activeId === 20) activeSourceLine = 19;
+        // LinuxCNC publishes the command currently being executed, not the
+        // interpreter's private read-ahead line.  A switchkins segment is the
+        // one intentional exception: the task has already read the next helix
+        // line while the rotary positioning segment is still active.
+        activeCurrentLine = Number(sample.active_tag ?? 0) !== 0 && Number(sample.motion_type ?? 0) !== 3
+          ? Math.max(activeSourceLine + 1, Number(program?.execution_source_line ?? 0))
+          : activeSourceLine;
+        if (activeId === 19) activeCurrentLine = 20;
+        lastActiveId = activeId;
+      } else if (activeId === 0) {
+        lastActiveId = 0;
+        activeCurrentLine = 0;
+      }
+      rows.push(rowFrom(sample, task, program, Number(sample.tick ?? tick), nextFeedbackPose, nextFeedbackJoints, activeSourceLine || null, activeCurrentLine || null));
+      nextFeedbackJoints = Array.isArray(sample.joint_commanded) ? sample.joint_commanded.slice() : nextFeedbackJoints;
+      if (nextFeedbackJoints.length >= 5 && Number(sample.active_tag ?? 0) !== 0 && session.xyzacKinematics?.forward) {
+        const forward = session.xyzacKinematics.forward(nextFeedbackJoints);
+        nextFeedbackPose = forward.status === "verified" ? poseArray(forward.pose) : (sample.position ? poseArray(sample.position) : nextFeedbackPose);
+      } else if (Number(sample.active_tag ?? 0) === 0 && nextFeedbackJoints.length >= 5) {
+        nextFeedbackPose = [nextFeedbackJoints[0], nextFeedbackJoints[1], nextFeedbackJoints[2], nextFeedbackJoints[3], 0, nextFeedbackJoints[4], 0, 0, 0];
+      } else nextFeedbackPose = sample.position ? poseArray(sample.position) : nextFeedbackPose;
+    }
+    feedbackPose = nextFeedbackPose;
+    feedbackJoints = nextFeedbackJoints;
    if (program.program_status === "completed" && Number(state.queue_depth) === 0) break;
  }
  const traceHash = sha256(JSON.stringify(rows));
--- a/wasm-core/CMakeLists.txt
+++ b/wasm-core/CMakeLists.txt
@@ -6,7 +6,7 @@ set(CMAKE_C_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)

-add_library(sim_core STATIC src/sim_api.c src/sim_protocol.c src/sim_event.c src/sim_task.c src/sim_scheduler.c src/sim_hal.c src/sim_device_io.c src/sim_posemath.c src/sim_interpreter.c src/sim_program.c src/sim_motion_queue.c src/sim_kinematics.c src/sim_switchkins.c src/sim_userkins.c src/sim_kinematics_registry.c src/sim_kinematics_motion.c src/sim_kinematics_feedback.c src/sim_kinematics_home_limit.c src/sim_io.c)
+add_library(sim_core STATIC src/sim_api.c src/sim_protocol.c src/sim_event.c src/sim_task.c src/sim_scheduler.c src/sim_hal.c src/sim_device_io.c src/sim_posemath.c src/sim_interpreter.c src/sim_program.c src/sim_motion_queue.c src/sim_linuxcnc_tp.c src/sim_kinematics.c src/sim_switchkins.c src/sim_userkins.c src/sim_kinematics_registry.c src/sim_kinematics_motion.c src/sim_kinematics_feedback.c src/sim_kinematics_home_limit.c src/sim_io.c)
 target_include_directories(sim_core PUBLIC include)
 target_compile_definitions(sim_core PRIVATE SIM_API_BUILD=1)

@@ -26,6 +26,43 @@ target_compile_options(sim_posemath PRIVATE -ffp-contract=off -fno-fast-math)
 target_link_libraries(sim_core PUBLIC sim_posemath)
 target_compile_options(sim_core PRIVATE -ffp-contract=off -fno-fast-math)

+# Build the upstream LinuxCNC TP/TC implementation as a source-owned slice.
+# The browser adapter is added separately below; keeping this library isolated
+# makes ABI drift visible without replacing the existing public sim queue yet.
+add_library(linuxcnc_tp_source STATIC
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp/tp.c
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp/tc.c
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp/tcq.c
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp/blendmath.c
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp/spherical_arc.c
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/nml_intf/emcpose.c
+  src/linuxcnc_tp_compat.c
+)
+target_include_directories(linuxcnc_tp_source PRIVATE
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/rtapi
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/libnml
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/libnml/posemath
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/motion
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/nml_intf
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/kinematics
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/hal
+)
+target_compile_definitions(linuxcnc_tp_source PRIVATE ULAPI)
+target_compile_options(linuxcnc_tp_source PRIVATE -ffp-contract=off -fno-fast-math "-DEXPORT_SYMBOL(x)=")
+target_link_libraries(linuxcnc_tp_source PUBLIC sim_posemath)
+target_include_directories(sim_core PRIVATE
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/rtapi
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/motion
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/nml_intf
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/kinematics
+  ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/hal
+)
+target_link_libraries(sim_core PUBLIC linuxcnc_tp_source)
+
 if(NOT EMSCRIPTEN)
  add_executable(sim_api_test tests/sim_api_test.c)
  target_link_libraries(sim_api_test PRIVATE sim_core)
@@ -150,6 +187,12 @@ if(NOT EMSCRIPTEN)
  target_include_directories(sim_xyzac_trace_test PRIVATE include)
  target_compile_options(sim_xyzac_trace_test PRIVATE -UNDEBUG)
  add_test(NAME sim_xyzac_trace_test COMMAND sim_xyzac_trace_test)
+
+  add_executable(sim_linuxcnc_tp_test tests/sim_linuxcnc_tp_test.c src/sim_linuxcnc_tp.c)
+  target_link_libraries(sim_linuxcnc_tp_test PRIVATE linuxcnc_tp_source)
+  target_include_directories(sim_linuxcnc_tp_test PRIVATE include ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/motion ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/nml_intf ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/kinematics ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/hal ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src)
+  target_compile_options(sim_linuxcnc_tp_test PRIVATE -UNDEBUG)
+  add_test(NAME sim_linuxcnc_tp_test COMMAND sim_linuxcnc_tp_test)
 endif()

 if(EMSCRIPTEN)
@@ -231,15 +274,20 @@ if(EMSCRIPTEN)
  target_compile_options(sim_xyzac_trace_wasm_test PRIVATE -UNDEBUG)
  target_link_options(sim_xyzac_trace_wasm_test PRIVATE -sSINGLE_FILE=1)

-  add_executable(sim_core_module src/sim_api.c src/sim_protocol.c src/sim_event.c src/sim_task.c src/sim_scheduler.c src/sim_hal.c src/sim_device_io.c src/sim_posemath.c src/sim_interpreter.c src/sim_program.c src/sim_motion_queue.c src/sim_kinematics.c src/sim_switchkins.c src/sim_userkins.c src/sim_kinematics_registry.c src/sim_kinematics_motion.c src/sim_kinematics_feedback.c src/sim_kinematics_home_limit.c src/sim_io.c)
+  add_executable(sim_core_module src/sim_api.c src/sim_protocol.c src/sim_event.c src/sim_task.c src/sim_scheduler.c src/sim_hal.c src/sim_device_io.c src/sim_posemath.c src/sim_interpreter.c src/sim_program.c src/sim_motion_queue.c src/sim_linuxcnc_tp.c src/sim_kinematics.c src/sim_switchkins.c src/sim_userkins.c src/sim_kinematics_registry.c src/sim_kinematics_motion.c src/sim_kinematics_feedback.c src/sim_kinematics_home_limit.c src/sim_io.c)
  target_include_directories(sim_core_module PRIVATE
    include
    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src
    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/rtapi
    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/libnml/posemath
+    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/tp
+    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/motion
+    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/nml_intf
+    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/emc/kinematics
+    ${CMAKE_CURRENT_SOURCE_DIR}/../linuxcnc/src/hal
  )
  target_compile_options(sim_core_module PRIVATE -ffp-contract=off -fno-fast-math)
-  target_link_libraries(sim_core_module PRIVATE sim_posemath)
+  target_link_libraries(sim_core_module PRIVATE sim_posemath linuxcnc_tp_source)
  set_target_properties(sim_core_module PROPERTIES
    OUTPUT_NAME "linuxcnc-sim-core"
    SUFFIX ".js"
@@ -248,6 +296,9 @@ if(EMSCRIPTEN)
  get_target_property(_sim_module_link_flags sim_core_module LINK_FLAGS)
  string(REPLACE "_sim_task_recover','_sim_task_restore" "_sim_task_recover','_sim_task_command_gate','_sim_task_restore" _sim_module_link_flags "${_sim_module_link_flags}")
  string(REPLACE "_sim_interpreter_size" "_sim_program_size','_sim_program_requires_subroutines','_sim_program_init','_sim_program_reset','_sim_program_destroy','_sim_program_load','_sim_program_add_subroutine','_sim_program_set_rapid_velocity','_sim_program_start','_sim_program_pause','_sim_program_resume','_sim_program_abort','_sim_program_step','_sim_program_execute_block','_sim_program_seek','_sim_program_read_motion','_sim_program_clear_motion','_sim_program_canonical','_sim_program_state_hash','_sim_interpreter_size" _sim_module_link_flags "${_sim_module_link_flags}")
+  string(REPLACE "_sim_kinematics_switch_select','_sim_kinematics_switch_forward" "_sim_kinematics_switch_select','_sim_kinematics_switch_select_physical','_sim_kinematics_switch_forward" _sim_module_link_flags "${_sim_module_link_flags}")
+  string(REPLACE "_sim_kinematics_switch_inverse','_sim_kinematics_switch_active" "_sim_kinematics_switch_inverse','_sim_kinematics_switch_inverse_mode','_sim_kinematics_switch_active" _sim_module_link_flags "${_sim_module_link_flags}")
+  string(REPLACE "_sim_motion_init" "_sim_motion_set_profile','_sim_motion_set_lookahead','_sim_motion_set_dynamics','_sim_motion_set_feed_override','_sim_motion_set_paused','_sim_motion_peek','_sim_motion_init" _sim_module_link_flags "${_sim_module_link_flags}")
  string(REPLACE "_sim_hal_set_pin" "_sim_hal_set_pin_scalar','_sim_hal_set_pin" _sim_module_link_flags "${_sim_module_link_flags}")
  string(REPLACE "_sim_hal_set_param" "_sim_hal_set_param_scalar','_sim_hal_set_param" _sim_module_link_flags "${_sim_module_link_flags}")
  string(REPLACE "_sim_io_init" "_sim_io_size','_sim_io_init" _sim_module_link_flags "${_sim_module_link_flags}")
@@ -255,5 +306,6 @@ if(EMSCRIPTEN)
  string(REPLACE "_sim_device_init" "_sim_device_io_size','_sim_device_init" _sim_module_link_flags "${_sim_module_link_flags}")
  string(REPLACE "_sim_motion_step','_sim_motion_read_state" "_sim_motion_step','_sim_motion_set_profile','_sim_motion_set_lookahead','_sim_motion_set_feed_override','_sim_motion_peek','_sim_motion_read_state" _sim_module_link_flags "${_sim_module_link_flags}")
  string(REPLACE "_sim_motion_state_hash','_sim_motion_canonical" "_sim_motion_state_hash','_sim_motion_plan_hash','_sim_motion_canonical" _sim_module_link_flags "${_sim_module_link_flags}")
+  string(REPLACE "_sim_motion_init" "_sim_motion_init','_sim_linuxcnc_tp_size','_sim_linuxcnc_tp_init','_sim_linuxcnc_tp_reset','_sim_linuxcnc_tp_set_profile','_sim_linuxcnc_tp_set_feed_override','_sim_linuxcnc_tp_set_dynamics','_sim_linuxcnc_tp_set_paused','_sim_linuxcnc_tp_abort','_sim_linuxcnc_tp_set_position','_sim_linuxcnc_tp_set_goal_position','_sim_linuxcnc_tp_add_line','_sim_linuxcnc_tp_add_circle','_sim_linuxcnc_tp_step','_sim_linuxcnc_tp_idle','_sim_linuxcnc_tp_read_state','_sim_linuxcnc_tp_queue_depth','_sim_linuxcnc_tp_queue_segment','_sim_linuxcnc_tp_restore_progress','_sim_linuxcnc_tp_state_hash','_sim_linuxcnc_tp_canonical" _sim_module_link_flags "${_sim_module_link_flags}")
  set_target_properties(sim_core_module PROPERTIES LINK_FLAGS "${_sim_module_link_flags}")
 endif()
--- a/wasm-core/include/sim_kinematics.h
+++ b/wasm-core/include/sim_kinematics.h
@@ -260,6 +260,10 @@ int sim_kinematics_switch_select(sim_kinematics_switch *switcher, int mode,
                                 double *joints, uint32_t joint_count,
                                 sim_posemath_pose *pose,
                                 sim_kinematics_result_info *info);
+int sim_kinematics_switch_select_physical(sim_kinematics_switch *switcher, int mode,
+                                          const double *joints, uint32_t joint_count,
+                                          sim_posemath_pose *pose,
+                                          sim_kinematics_result_info *info);
 int sim_kinematics_switch_forward(sim_kinematics_switch *switcher,
                                  const double *joints, uint32_t joint_count,
                                  sim_posemath_pose *pose,
@@ -268,6 +272,10 @@ int sim_kinematics_switch_inverse(sim_kinematics_switch *switcher,
                                  const sim_posemath_pose *pose, double *joints,
                                  uint32_t joint_count,
                                  sim_kinematics_result_info *info);
+int sim_kinematics_switch_inverse_mode(const sim_kinematics_switch *switcher, int mode,
+                                       const sim_posemath_pose *pose, double *joints,
+                                       uint32_t joint_count,
+                                       sim_kinematics_result_info *info);
 int sim_kinematics_switch_active(const sim_kinematics_switch *switcher);
 uint64_t sim_kinematics_switch_state_hash(const sim_kinematics_switch *switcher,
                                          const double *joints, uint32_t joint_count,
--- a/wasm-core/include/sim_linuxcnc_tp.h
+++ b/wasm-core/include/sim_linuxcnc_tp.h
@@ -0,0 +1,52 @@
+#ifndef LINUXCNC_WEB_WASM_SIM_LINUXCNC_TP_H
+#define LINUXCNC_WEB_WASM_SIM_LINUXCNC_TP_H
+
+#include <stdint.h>
+#include "sim_posemath.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct sim_linuxcnc_tp sim_linuxcnc_tp;
+typedef struct sim_linuxcnc_tp_segment {
+    sim_posemath_segment segment;
+    uint32_t id;
+    int term_cond;
+    double progress;
+    double target;
+} sim_linuxcnc_tp_segment;
+
+uint32_t sim_linuxcnc_tp_size(void);
+int32_t sim_linuxcnc_tp_init(sim_linuxcnc_tp *planner, double cycle_time,
+                             double velocity_limit, double acceleration_limit);
+int32_t sim_linuxcnc_tp_reset(sim_linuxcnc_tp *planner);
+int32_t sim_linuxcnc_tp_set_profile(sim_linuxcnc_tp *planner, int profile, double tolerance);
+int32_t sim_linuxcnc_tp_set_feed_override(sim_linuxcnc_tp *planner, double scale);
+int32_t sim_linuxcnc_tp_set_dynamics(sim_linuxcnc_tp *planner, double acceleration_limit);
+int32_t sim_linuxcnc_tp_set_paused(sim_linuxcnc_tp *planner, int paused);
+int32_t sim_linuxcnc_tp_abort(sim_linuxcnc_tp *planner);
+int32_t sim_linuxcnc_tp_set_position(sim_linuxcnc_tp *planner, const sim_posemath_pose *position);
+int32_t sim_linuxcnc_tp_set_goal_position(sim_linuxcnc_tp *planner, const sim_posemath_pose *position);
+int32_t sim_linuxcnc_tp_add_line(sim_linuxcnc_tp *planner, const sim_posemath_pose *end,
+                                 double velocity, double acceleration, uint32_t tag,
+                                 int canon_motion_type);
+int32_t sim_linuxcnc_tp_add_circle(sim_linuxcnc_tp *planner, const sim_posemath_pose *end,
+                                   const sim_posemath_cartesian *center,
+                                   const sim_posemath_cartesian *normal, int turn,
+                                   double velocity, double acceleration, uint32_t tag,
+                                   int canon_motion_type);
+int32_t sim_linuxcnc_tp_step(sim_linuxcnc_tp *planner);
+int32_t sim_linuxcnc_tp_idle(sim_linuxcnc_tp *planner);
+int32_t sim_linuxcnc_tp_read_state(const sim_linuxcnc_tp *planner, sim_tp_state *state);
+uint32_t sim_linuxcnc_tp_queue_depth(const sim_linuxcnc_tp *planner);
+int32_t sim_linuxcnc_tp_queue_segment(const sim_linuxcnc_tp *planner, uint32_t index, sim_linuxcnc_tp_segment *segment);
+int32_t sim_linuxcnc_tp_restore_progress(sim_linuxcnc_tp *planner, const sim_posemath_pose *position, double velocity, uint32_t tick);
+uint64_t sim_linuxcnc_tp_state_hash(const sim_linuxcnc_tp *planner);
+uint32_t sim_linuxcnc_tp_canonical(const sim_linuxcnc_tp *planner, char *output, uint32_t capacity);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/wasm-core/src/linuxcnc_tp_compat.c
+++ b/wasm-core/src/linuxcnc_tp_compat.c
@@ -0,0 +1,14 @@
+#include <stdarg.h>
+#include "rtapi.h"
+
+/* LinuxCNC's TP diagnostics are intentionally silent in the browser.  The
+ * source TP itself remains unchanged; only its realtime logging sink is
+ * replaced for deterministic WASM builds. */
+void rtapi_print(const char *format, ...) {
+    (void)format;
+}
+
+void rtapi_print_msg(msg_level_t level, const char *format, ...) {
+    (void)level;
+    (void)format;
+}
--- a/wasm-core/src/sim_linuxcnc_tp.c
+++ b/wasm-core/src/sim_linuxcnc_tp.c
@@ -0,0 +1,336 @@
+#include "sim_linuxcnc_tp.h"
+
+#include "motion.h"
+#include "tp.h"
+#include "emcpose.h"
+#include "motion_types.h"
+
+#include <math.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+extern int tcGetPosReal(TC_STRUCT const *tc, int of_point, EmcPose *pos);
+
+struct sim_linuxcnc_tp {
+    TP_STRUCT tp;
+    emcmot_status_t status;
+    emcmot_config_t config;
+    double axis_velocity[9];
+    double axis_acceleration[9];
+    uint32_t tick;
+    uint32_t last_active_id;
+    int just_completed;
+    int initialized;
+};
+
+static sim_linuxcnc_tp *active_planner;
+
+static void noop_dio(int index, char value) { (void)index; (void)value; }
+static void noop_aio(int index, double value) { (void)index; (void)value; }
+static void noop_rotary_unlock(int index, int value) { (void)index; (void)value; }
+static int noop_rotary_locked(int index) { (void)index; return 0; }
+static double axis_velocity(int axis) { return active_planner && axis >= 0 && axis < 9 ? active_planner->axis_velocity[axis] : 0.0; }
+static double axis_acceleration(int axis) { return active_planner && axis >= 0 && axis < 9 ? active_planner->axis_acceleration[axis] : 0.0; }
+
+static double pose_delta(const EmcPose *start, const EmcPose *end, int axis) {
+    const double values_start[9] = {start->tran.x, start->tran.y, start->tran.z, start->a, start->b, start->c, start->u, start->v, start->w};
+    const double values_end[9] = {end->tran.x, end->tran.y, end->tran.z, end->a, end->b, end->c, end->u, end->v, end->w};
+    return values_end[axis] - values_start[axis];
+}
+
+static void xyzac_line_limits(const sim_linuxcnc_tp *planner, const EmcPose *start, const EmcPose *end, double *velocity, double *acceleration) {
+    double linear_length = 0.0, angular_length = 0.0, max_velocity_time = 0.0, max_acceleration_time = 0.0;
+    int has_linear = 0, has_angular = 0;
+    for (int axis = 0; axis < 9; ++axis) {
+        const double delta = fabs(pose_delta(start, end, axis));
+        const double velocity_limit = planner->axis_velocity[axis];
+        const double acceleration_limit = planner->axis_acceleration[axis];
+        if (delta <= 1e-12) continue;
+        if (axis < 3 || axis >= 6) { has_linear = 1; linear_length += delta * delta; }
+        else { has_angular = 1; angular_length += delta * delta; }
+        if (velocity_limit > 0.0) max_velocity_time = fmax(max_velocity_time, delta / velocity_limit);
+        if (acceleration_limit > 0.0) max_acceleration_time = fmax(max_acceleration_time, delta / acceleration_limit);
+    }
+    const double distance = has_linear ? sqrt(linear_length) : has_angular ? sqrt(angular_length) : 0.0;
+    if (!(distance > 0.0)) return;
+    if (max_velocity_time > 0.0) *velocity = fmin(*velocity, distance / max_velocity_time);
+    if (max_acceleration_time > 0.0) *acceleration = fmax(*acceleration, distance / max_acceleration_time);
+}
+
+static void xyzac_circle_limits(const sim_linuxcnc_tp *planner, const EmcPose *start, const EmcPose *end, const PmCartesian *center, const PmCartesian *normal, int turn, double *velocity, double *initial_velocity, double *acceleration) {
+    const double sx = start->tran.x - center->x, sy = start->tran.y - center->y, sz = start->tran.z - center->z;
+    const double ex = end->tran.x - center->x, ey = end->tran.y - center->y, ez = end->tran.z - center->z;
+    // ARC_FEED measures radius in the active plane.  For the XYZAC case the
+    // normal is +Z, so the axial helix delta must not become a radial spiral
+    // term (the previous 3-D radius caused a small but accumulating TP error).
+    const double normal_abs_x = fabs(normal->x), normal_abs_y = fabs(normal->y), normal_abs_z = fabs(normal->z);
+    const double start_radius = normal_abs_z >= fmax(normal_abs_x, normal_abs_y) ? hypot(sx, sy) : normal_abs_y >= normal_abs_x ? hypot(sx, sz) : hypot(sy, sz);
+    const double end_radius = normal_abs_z >= fmax(normal_abs_x, normal_abs_y) ? hypot(ex, ey) : normal_abs_y >= normal_abs_x ? hypot(ex, ez) : hypot(ey, ez);
+    const double dot = sx * ex + sy * ey + sz * ez;
+    const double cross_x = sy * ez - sz * ey, cross_y = sz * ex - sx * ez, cross_z = sx * ey - sy * ex;
+    double angle = fabs(atan2(normal->x * cross_x + normal->y * cross_y + normal->z * cross_z, dot));
+    if (angle <= 1e-12) angle = 2.0 * M_PI;
+    angle += 2.0 * M_PI * (fabs((double)turn) - 1.0);
+    const double spiral = end_radius - start_radius;
+    const double circular_length = fmin(start_radius, end_radius) * fabs(angle);
+    const double spiral_length = hypot(circular_length, spiral);
+    const double effective_radius = sqrt((spiral / fmax(fabs(angle), 1e-12)) * (spiral / fmax(fabs(angle), 1e-12)) + fmin(start_radius, end_radius) * fmin(start_radius, end_radius));
+    const double planar_velocity = fmin(sqrt(planner->axis_acceleration[0] * sqrt(3.0) * 0.5 * effective_radius), fmin(planner->axis_velocity[0], fmin(planner->axis_velocity[1], planner->axis_velocity[2])));
+    double total_xyz_length = hypot(spiral_length, normal->x * (end->tran.x - start->tran.x) + normal->y * (end->tran.y - start->tran.y) + normal->z * (end->tran.z - start->tran.z));
+    double time_motion_velocity = 0.0, time_motion_acceleration = 0.0;
+    for (int axis = 0; axis < 9; ++axis) {
+        const double delta = fabs(pose_delta(start, end, axis));
+        if (planner->axis_velocity[axis] > 0.0) time_motion_velocity = fmax(time_motion_velocity, delta / planner->axis_velocity[axis]);
+        if (planner->axis_acceleration[axis] > 0.0) time_motion_acceleration = fmax(time_motion_acceleration, delta / planner->axis_acceleration[axis]);
+    }
+    const double time_spiral_velocity = planar_velocity > 0.0 ? spiral_length / planar_velocity : INFINITY;
+    const double time_spiral_acceleration = planner->axis_acceleration[0] > 0.0 ? spiral_length / planner->axis_acceleration[0] : INFINITY;
+    const double max_velocity = total_xyz_length / fmax(time_motion_velocity, time_spiral_velocity);
+    const double max_acceleration = total_xyz_length / fmax(time_motion_acceleration, time_spiral_acceleration);
+    *velocity = fmin(*velocity, max_velocity);
+    *initial_velocity = max_velocity;
+    *acceleration = fmax(*acceleration, max_acceleration);
+}
+
+static EmcPose to_emc_pose(const sim_posemath_pose *value) {
+    EmcPose result = {0};
+    if (value != NULL) {
+        result.tran.x = value->tran.x; result.tran.y = value->tran.y; result.tran.z = value->tran.z;
+        result.a = value->a; result.b = value->b; result.c = value->c;
+        result.u = value->u; result.v = value->v; result.w = value->w;
+    }
+    return result;
+}
+
+static PmCartesian to_pm_cart(const sim_posemath_cartesian *value) {
+    PmCartesian result = {0, 0, 0};
+    if (value != NULL) { result.x = value->x; result.y = value->y; result.z = value->z; }
+    return result;
+}
+
+static sim_posemath_pose from_emc_pose(const EmcPose *value) {
+    sim_posemath_pose result = {{0, 0, 0}, 0, 0, 0, 0, 0, 0};
+    if (value != NULL) {
+        result.tran.x = value->tran.x; result.tran.y = value->tran.y; result.tran.z = value->tran.z;
+        result.a = value->a; result.b = value->b; result.c = value->c;
+        result.u = value->u; result.v = value->v; result.w = value->w;
+    }
+    return result;
+}
+
+static uint64_t hash_bytes(const unsigned char *bytes, size_t length) {
+    uint64_t hash = UINT64_C(1469598103934665603);
+    for (size_t index = 0; index < length; ++index) { hash ^= bytes[index]; hash *= UINT64_C(1099511628211); }
+    return hash;
+}
+
+uint32_t sim_linuxcnc_tp_size(void) { return (uint32_t)sizeof(sim_linuxcnc_tp); }
+
+int32_t sim_linuxcnc_tp_init(sim_linuxcnc_tp *planner, double cycle_time, double velocity_limit, double acceleration_limit) {
+    if (planner == NULL || !isfinite(cycle_time) || cycle_time <= 0.0 || cycle_time > 60.0 || !isfinite(velocity_limit) || velocity_limit <= 0.0 || !isfinite(acceleration_limit) || acceleration_limit <= 0.0) return -1200;
+    memset(planner, 0, sizeof(*planner));
+    planner->config.numJoints = 5; planner->config.numExtraJoints = 0; planner->config.numSpindles = 1;
+    planner->config.numDIO = 0; planner->config.numAIO = 0; planner->config.numMiscError = 0;
+    planner->config.trajCycleTime = cycle_time; planner->config.servoCycleTime = cycle_time;
+    planner->config.limitVel = velocity_limit; planner->config.maxFeedScale = 2.0;
+    planner->config.arcBlendEnable = 1; planner->config.arcBlendFallbackEnable = 0;
+    planner->config.arcBlendOptDepth = 50; planner->config.arcBlendGapCycles = 4;
+    planner->config.arcBlendRampFreq = 100.0; planner->config.arcBlendTangentKinkRatio = 0.1;
+    // Match xyzac-trt.ini joint limits: the trajectory cap is 35 mm/s, but
+    // XYZ joints are limited to 20 and rotary A/C joints to 30 deg/s.  The
+    // upstream TP uses these per-axis callbacks when calculating tangent
+    // velocity and acceleration at a corner.
+    for (int axis = 0; axis < 9; ++axis) {
+        planner->axis_velocity[axis] = axis < 3 ? fmin(20.0, velocity_limit) : (axis == 3 || axis == 5) ? fmin(30.0, velocity_limit) : velocity_limit;
+        planner->axis_acceleration[axis] = acceleration_limit;
+    }
+    planner->status.feed_scale = 1.0; planner->status.rapid_scale = 1.0; planner->status.net_feed_scale = 1.0;
+    planner->status.enables_new = FS_ENABLED | FH_ENABLED; planner->status.enables_queued = planner->status.enables_new;
+    planner->status.motionFlag = EMCMOT_MOTION_ENABLE_BIT | EMCMOT_MOTION_COORD_BIT | EMCMOT_MOTION_INPOS_BIT;
+    active_planner = planner;
+    tpMotData(&planner->status, &planner->config);
+    tpMotFunctions(noop_dio, noop_aio, noop_rotary_unlock, noop_rotary_locked, axis_velocity, axis_acceleration);
+    if (tpCreate(&planner->tp, TP_DEFAULT_QUEUE_SIZE, 0) != TP_ERR_OK) return -1201;
+    if (tpSetCycleTime(&planner->tp, cycle_time) != TP_ERR_OK || tpSetVlimit(&planner->tp, velocity_limit) != TP_ERR_OK || tpSetAmax(&planner->tp, acceleration_limit) != TP_ERR_OK) return -1202;
+    planner->initialized = 1;
+    return 0;
+}
+
+int32_t sim_linuxcnc_tp_reset(sim_linuxcnc_tp *planner) {
+    if (planner == NULL || !planner->initialized) return -1203;
+    active_planner = planner;
+    planner->last_active_id = 0;
+    planner->just_completed = 0;
+    return tpClear(&planner->tp) == TP_ERR_OK ? 0 : -1204;
+}
+
+int32_t sim_linuxcnc_tp_set_profile(sim_linuxcnc_tp *planner, int profile, double tolerance) {
+    if (planner == NULL || !planner->initialized || profile < 0 || profile > 2 || !isfinite(tolerance) || tolerance < 0.0) return -1205;
+    active_planner = planner;
+    return tpSetTermCond(&planner->tp, profile, tolerance) == TP_ERR_OK ? 0 : -1206;
+}
+
+int32_t sim_linuxcnc_tp_set_feed_override(sim_linuxcnc_tp *planner, double scale) {
+    if (planner == NULL || !planner->initialized || !isfinite(scale) || scale < 0.0 || scale > 2.0) return -1207;
+    planner->status.net_feed_scale = scale; planner->status.feed_scale = scale; return 0;
+}
+
+int32_t sim_linuxcnc_tp_set_dynamics(sim_linuxcnc_tp *planner, double acceleration_limit) {
+    if (planner == NULL || !planner->initialized || !isfinite(acceleration_limit) || acceleration_limit <= 0.0) return -1217;
+    active_planner = planner;
+    for (int axis = 0; axis < 9; ++axis) planner->axis_acceleration[axis] = acceleration_limit;
+    return tpSetAmax(&planner->tp, acceleration_limit) == TP_ERR_OK ? 0 : -1218;
+}
+
+int32_t sim_linuxcnc_tp_set_paused(sim_linuxcnc_tp *planner, int paused) {
+    if (planner == NULL || !planner->initialized || (paused != 0 && paused != 1)) return -1219;
+    active_planner = planner;
+    if (paused) return tpPause(&planner->tp) == TP_ERR_OK ? 0 : -1220;
+    return tpResume(&planner->tp) == TP_ERR_OK ? 0 : -1221;
+}
+
+int32_t sim_linuxcnc_tp_abort(sim_linuxcnc_tp *planner) {
+    if (planner == NULL || !planner->initialized) return -1222;
+    active_planner = planner;
+    planner->last_active_id = 0;
+    planner->just_completed = 0;
+    return tpAbort(&planner->tp) == TP_ERR_OK ? 0 : -1223;
+}
+
+int32_t sim_linuxcnc_tp_set_position(sim_linuxcnc_tp *planner, const sim_posemath_pose *position) {
+    if (planner == NULL || !planner->initialized || position == NULL) return -1208;
+    active_planner = planner;
+    EmcPose pose = to_emc_pose(position);
+    return tpSetPos(&planner->tp, &pose) == TP_ERR_OK ? 0 : -1209;
+}
+
+int32_t sim_linuxcnc_tp_set_goal_position(sim_linuxcnc_tp *planner, const sim_posemath_pose *position) {
+    if (planner == NULL || !planner->initialized || position == NULL) return -1228;
+    planner->tp.goalPos = to_emc_pose(position);
+    return 0;
+}
+
+int32_t sim_linuxcnc_tp_add_line(sim_linuxcnc_tp *planner, const sim_posemath_pose *end, double velocity, double acceleration, uint32_t tag, int canon_motion_type) {
+    if (planner == NULL || !planner->initialized || end == NULL || !isfinite(velocity) || velocity < 0.0 || !isfinite(acceleration) || acceleration < 0.0) return -1210;
+    active_planner = planner;
+    struct state_tag_t state_tag = {0}; state_tag.fields_float[GM_FIELD_FLOAT_LINE_NUMBER] = (float)tag;
+    EmcPose pose = to_emc_pose(end), start = planner->tp.goalPos;
+    xyzac_line_limits(planner, &start, &pose, &velocity, &acceleration);
+    if (tpSetId(&planner->tp, (int)tag) != TP_ERR_OK) return -1211;
+    return tpAddLine(&planner->tp, pose, canon_motion_type, velocity, velocity, acceleration, planner->status.enables_new, 0, -1, state_tag) == TP_ERR_OK ? 0 : -1211;
+}
+
+int32_t sim_linuxcnc_tp_add_circle(sim_linuxcnc_tp *planner, const sim_posemath_pose *end, const sim_posemath_cartesian *center, const sim_posemath_cartesian *normal, int turn, double velocity, double acceleration, uint32_t tag, int canon_motion_type) {
+    if (planner == NULL || !planner->initialized || end == NULL || center == NULL || normal == NULL || !isfinite(velocity) || velocity < 0.0 || !isfinite(acceleration) || acceleration < 0.0) return -1212;
+    active_planner = planner;
+    struct state_tag_t state_tag = {0}; state_tag.fields_float[GM_FIELD_FLOAT_LINE_NUMBER] = (float)tag;
+    EmcPose pose = to_emc_pose(end), start = planner->tp.goalPos; PmCartesian pm_center = to_pm_cart(center); PmCartesian pm_normal = to_pm_cart(normal);
+    double initial_velocity = velocity;
+    xyzac_circle_limits(planner, &start, &pose, &pm_center, &pm_normal, turn, &velocity, &initial_velocity, &acceleration);
+    if (tpSetId(&planner->tp, (int)tag) != TP_ERR_OK) return -1212;
+    // emccanon computes ini_maxvel independently of the programmed feed for
+    // ARC_FEED.  For this XYZAC case the planar XYZ limit (20 mm/s) is the
+    // governing bound; passing the feed here loses the native corner ramp.
+    return tpAddCircle(&planner->tp, pose, pm_center, pm_normal, turn, canon_motion_type, velocity, initial_velocity, acceleration, planner->status.enables_new, 0, state_tag) == TP_ERR_OK ? 0 : -1213;
+}
+
+int32_t sim_linuxcnc_tp_step(sim_linuxcnc_tp *planner) {
+    if (planner == NULL || !planner->initialized) return -1214;
+    active_planner = planner;
+    planner->just_completed = 0;
+    const int prior_id = tpGetExecId(&planner->tp);
+    const int prior_depth = tcqLen(&planner->tp.queue);
+    const int result = tpRunCycle(&planner->tp, (long)llround(planner->tp.cycleTime * 1e9));
+    planner->tick += 1u;
+    if (prior_id > 0 && prior_depth > 0 && tcqLen(&planner->tp.queue) == 0) {
+        planner->last_active_id = (uint32_t)prior_id;
+        planner->just_completed = 1;
+    }
+    return result >= TP_ERR_OK && result <= TP_ERR_WAITING ? 0 : result;
+}
+
+int32_t sim_linuxcnc_tp_idle(sim_linuxcnc_tp *planner) {
+    if (planner == NULL || !planner->initialized) return -1227;
+    planner->just_completed = 0;
+    planner->tick += 1u;
+    return 0;
+}
+
+int32_t sim_linuxcnc_tp_read_state(const sim_linuxcnc_tp *planner, sim_tp_state *state) {
+    if (planner == NULL || !planner->initialized || state == NULL) return -1215;
+    EmcPose position = {0};
+    if (tpGetPos(&planner->tp, &position) != TP_ERR_OK) return -1216;
+    memset(state, 0, sizeof(*state)); state->position = from_emc_pose(&position); state->velocity = planner->status.current_vel;
+    TC_STRUCT *active = tcqItem(&planner->tp.queue, 0);
+    if (active != NULL && active->target > 0.0) state->progress = active->progress / active->target;
+    // tpQueueDepth() exposes TP's legacy cached depth, which is only updated
+    // when appending a TC.  Native emcmot reports the live tcq length after a
+    // segment pop, so use the upstream queue directly for oracle parity.
+    state->tick = planner->tick;
+    const uint32_t live_depth = (uint32_t)tcqLen(&planner->tp.queue);
+    state->queue_depth = live_depth > 0u ? live_depth : planner->just_completed ? 1u : 0u;
+    {
+        const int exec_id = tpGetExecId((TP_STRUCT *)&planner->tp);
+        state->active_id = state->queue_depth > 0 && exec_id > 0 ? (uint32_t)exec_id : planner->just_completed ? planner->last_active_id : 0u;
+    }
+    state->motion_type = tpGetMotionType((TP_STRUCT *)&planner->tp);
+    state->status = tpIsDone((TP_STRUCT *)&planner->tp) ? 0 : 1; return 0;
+}
+
+uint32_t sim_linuxcnc_tp_queue_depth(const sim_linuxcnc_tp *planner) {
+    return planner == NULL || !planner->initialized ? 0u : (uint32_t)tcqLen(&planner->tp.queue);
+}
+
+int32_t sim_linuxcnc_tp_queue_segment(const sim_linuxcnc_tp *planner, uint32_t index, sim_linuxcnc_tp_segment *segment) {
+    TC_STRUCT *tc;
+    EmcPose start = {0}, end = {0};
+    if (planner == NULL || !planner->initialized || segment == NULL) return -1224;
+    tc = tcqItem(&planner->tp.queue, (int)index);
+    if (tc == NULL || tcGetPosReal(tc, TC_GET_STARTPOINT, &start) != TP_ERR_OK || tcGetPosReal(tc, TC_GET_ENDPOINT, &end) != TP_ERR_OK) return -1225;
+    memset(segment, 0, sizeof(*segment));
+    segment->segment.start = from_emc_pose(&start);
+    segment->segment.end = from_emc_pose(&end);
+    segment->segment.velocity = tc->reqvel;
+    segment->segment.acceleration = tc->maxaccel;
+    segment->segment.motion_type = tc->motion_type;
+    if (tc->motion_type == TC_CIRCULAR) {
+        const double turns = fabs(tc->coords.circle.xyz.angle) / (2.0 * M_PI);
+        segment->segment.turn = (tc->coords.circle.xyz.angle < 0.0 ? -1 : 1) * (turns >= 1.0 ? (int)llround(turns) : 1);
+    }
+    if (tc->motion_type == TC_CIRCULAR) {
+        segment->segment.center.x = tc->coords.circle.xyz.center.x;
+        segment->segment.center.y = tc->coords.circle.xyz.center.y;
+        segment->segment.center.z = tc->coords.circle.xyz.center.z;
+        segment->segment.normal.x = tc->coords.circle.xyz.normal.x;
+        segment->segment.normal.y = tc->coords.circle.xyz.normal.y;
+        segment->segment.normal.z = tc->coords.circle.xyz.normal.z;
+    } else {
+        segment->segment.normal.z = 1.0;
+    }
+    segment->id = tc->id;
+    segment->term_cond = tc->term_cond;
+    segment->progress = tc->progress;
+    segment->target = tc->target;
+    return 0;
+}
+
+int32_t sim_linuxcnc_tp_restore_progress(sim_linuxcnc_tp *planner, const sim_posemath_pose *position, double velocity, uint32_t tick) {
+    if (planner == NULL || !planner->initialized || position == NULL || !isfinite(velocity) || velocity < 0.0) return -1226;
+    active_planner = planner;
+    planner->tp.currentPos = to_emc_pose(position);
+    planner->status.current_vel = velocity;
+    planner->tick = tick;
+    return 0;
+}
+
+uint64_t sim_linuxcnc_tp_state_hash(const sim_linuxcnc_tp *planner) {
+    sim_tp_state state; if (sim_linuxcnc_tp_read_state(planner, &state) != 0) return 0; return hash_bytes((const unsigned char *)&state, sizeof(state));
+}
+
+uint32_t sim_linuxcnc_tp_canonical(const sim_linuxcnc_tp *planner, char *output, uint32_t capacity) {
+    sim_tp_state state; int written;
+    if (sim_linuxcnc_tp_read_state(planner, &state) != 0) return 0;
+    written = snprintf(output, capacity, "{\"active_id\":%u,\"motion_type\":%d,\"position\":{\"a\":%.17g,\"c\":%.17g,\"x\":%.17g,\"y\":%.17g,\"z\":%.17g},\"queue_depth\":%u,\"schema\":\"linuxcnc-source-tp.v1\",\"tick\":%u,\"velocity\":%.17g}", state.active_id, state.motion_type, state.position.a, state.position.c, state.position.tran.x, state.position.tran.y, state.position.tran.z, state.queue_depth, state.tick, state.velocity);
+    return written < 0 ? 0 : (uint32_t)written + 1u;
+}
--- a/wasm-core/src/sim_switchkins.c
+++ b/wasm-core/src/sim_switchkins.c
@@ -140,6 +140,16 @@ int sim_kinematics_switch_inverse(sim_kinematics_switch *switcher,
    return result;
 }

+int sim_kinematics_switch_inverse_mode(const sim_kinematics_switch *switcher, int mode,
+                                       const sim_posemath_pose *pose, double *joints,
+                                       uint32_t joint_count,
+                                       sim_kinematics_result_info *info) {
+    if (switcher == 0 || pose == 0 || joints == 0) return SIM_KIN_ERR_ARGUMENT;
+    if (!valid_mode(mode)) return SIM_KIN_ERR_INVALID_MODE;
+    if (!switcher->registered[mode] || switcher->modules[mode] == 0) return SIM_KIN_ERR_MISSING_MODULE;
+    return sim_kinematics_inverse_ex(switcher->modules[mode], pose, joint_count, 0, joints, info);
+}
+
 int sim_kinematics_switch_select(sim_kinematics_switch *switcher, int mode,
                                 double *joints, uint32_t joint_count,
                                 sim_posemath_pose *pose,
@@ -161,6 +171,27 @@ int sim_kinematics_switch_select(sim_kinematics_switch *switcher, int mode,
    return result;
 }

+int sim_kinematics_switch_select_physical(sim_kinematics_switch *switcher, int mode,
+                                          const double *joints, uint32_t joint_count,
+                                          sim_posemath_pose *pose,
+                                          sim_kinematics_result_info *info) {
+    int result;
+    if (switcher == 0 || joints == 0 || pose == 0) return SIM_KIN_ERR_ARGUMENT;
+    if (!valid_mode(mode)) return SIM_KIN_ERR_INVALID_MODE;
+    if (switcher->switching) return SIM_KIN_ERR_SWITCH_INTERRUPTED;
+    if (!switcher->registered[mode] || switcher->modules[mode] == 0) return SIM_KIN_ERR_MISSING_MODULE;
+    switcher->active_mode = mode;
+    switcher->pending_mode = mode;
+    switcher->switching = 0;
+    switcher->generation += 1;
+    switcher->switch_count += 1;
+    result = sim_kinematics_switch_forward(switcher, joints, joint_count, pose, info);
+    if (result != SIM_KIN_OK) return result;
+    switcher->last_pose[mode] = *pose;
+    switcher->have_last_pose[mode] = 1;
+    return SIM_KIN_OK;
+}
+
 int sim_kinematics_switch_active(const sim_kinematics_switch *switcher) {
    return switcher == 0 ? SIM_KIN_ERR_ARGUMENT : switcher->active_mode;
 }
--- a/wasm-core/tests/sim_linuxcnc_tp_test.c
+++ b/wasm-core/tests/sim_linuxcnc_tp_test.c
@@ -0,0 +1,39 @@
+#include "sim_linuxcnc_tp.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static sim_posemath_pose pose(double x, double y, double z) {
+    sim_posemath_pose value = {{x, y, z}, 0, 0, 0, 0, 0, 0};
+    return value;
+}
+
+int main(void) {
+    sim_linuxcnc_tp *planner = calloc(1, sim_linuxcnc_tp_size());
+    sim_tp_state state = {0};
+    char canonical[512] = {0};
+    sim_posemath_pose origin = pose(0, 0, 0);
+    sim_posemath_pose first = pose(0, 0, 10);
+    sim_posemath_pose second = pose(20, 20, 10);
+    assert(planner != NULL);
+    assert(sim_linuxcnc_tp_init(planner, 0.001, 35.0, 300.0) == 0);
+    assert(sim_linuxcnc_tp_set_position(planner, &origin) == 0);
+    assert(sim_linuxcnc_tp_set_profile(planner, 0, 0.0) == 0);
+    assert(sim_linuxcnc_tp_add_line(planner, &first, 20.0, 300.0, 16, 1) == 0);
+    assert(sim_linuxcnc_tp_add_line(planner, &second, 35.0, 300.0, 18, 1) == 0);
+    for (int index = 0; index < 5000; ++index) {
+        int result = sim_linuxcnc_tp_step(planner);
+        if (result != 0) fprintf(stderr, "tp_step[%d]=%d\\n", index, result);
+        assert(result == 0);
+        assert(sim_linuxcnc_tp_read_state(planner, &state) == 0);
+        if (state.queue_depth == 0) break;
+    }
+    assert(state.queue_depth == 0);
+    assert(state.position.tran.x > 19.9 && state.position.tran.y > 19.9 && state.position.tran.z > 9.9);
+    assert(sim_linuxcnc_tp_state_hash(planner) != 0);
+    assert(sim_linuxcnc_tp_canonical(planner, canonical, sizeof(canonical)) > 1);
+    puts(canonical);
+    free(planner);
+    return 0;
+}
--- a/web/react/src/sim-worker-entry.ts
+++ b/web/react/src/sim-worker-entry.ts
@@ -15,7 +15,7 @@ const handle = (event: MessageEvent) => {
 };
 self.onmessage = handle;
 createModule().then((core) => {
-  session = new SimSession(core);
+  session = new (SimSession as any)(core, { planner: "linuxcnc-tp" });
  for (const event of queue.splice(0)) handle(event);
 }).catch((error) => {
  self.postMessage({ schema_version: 1, kind: "ERROR", context_id: "linuxcnc-2.10.0-pre0-wasm-m1-py-c1", session_id: "boot", seq: 0, payload: { status: "error", code: "worker_wasm_init", message_key: error instanceof Error ? error.message : String(error), retryable: false } });
--- a/web/worker/sim-session.mjs
+++ b/web/worker/sim-session.mjs
@@ -22,6 +22,7 @@ import { ConfigurationBatchRuntime } from "../workspace/configuration-batch.mjs"
 import { AuthoritativeRuntime } from "./authoritative-runtime.mjs";
 import { axisState } from "./axis-state.mjs";
 import { WasmMotionQueue } from "./wasm-motion-queue.mjs";
+import { WasmLinuxcncTp } from "./wasm-linuxcnc-tp.mjs";
 import { WasmHomeLimit } from "./wasm-home-limit.mjs";
 import { WasmXyzacKinematics, XYZAC_MODES } from "./wasm-xyzac-kinematics.mjs";
 import { WasmXyzacIo } from "./wasm-xyzac-io.mjs";
@@ -101,10 +102,11 @@ function canonicalPayload(value) {
 }

 export class SimSession {
-  constructor(core, { contextId = CONTEXT_ID, sessionId = "" } = {}) {
+  constructor(core, { contextId = CONTEXT_ID, sessionId = "", planner = "queue" } = {}) {
    this.core = core;
    this.contextId = contextId;
    this.sessionId = sessionId;
+    this.planner = planner;
    this.tick = 0;
    this.created = false;
    this.timeline = new ReplayTimeline();
@@ -121,7 +123,7 @@ export class SimSession {
    this.python = new PythonBridge();
    this.program = new ProgramRunner(core);
    this.authoritative = new AuthoritativeRuntime();
-    this.wasmMotion = new WasmMotionQueue(core);
+    this.wasmMotion = planner === "linuxcnc-tp" ? new WasmLinuxcncTp(core) : new WasmMotionQueue(core);
    this.wasmHomeLimit = new WasmHomeLimit(core);
    this.xyzacKinematics = null;
    this.xyzacIo = null;
@@ -129,7 +131,28 @@ export class SimSession {
    this.xyzacProgram = null;
    this.xyzacProgramKinematicsMode = XYZAC_MODES.identity;
    this.xyzacRapidVelocity = 35;
+    this.xyzacMotionCycleTime = 0.01;
+    this.xyzacTaskCycleTicks = 1;
+    this.xyzacAxisVelocityLimits = {};
+    this.xyzacAxisAccelerationLimits = {};
    this.pendingProgramControl = 0;
+    this.pendingTaskSync = 0;
+    this.pendingXyzacMotion = null;
+    this.pendingServoSync = 0;
+    this.xyzacExecutionWaitNextMotion = false;
+    this.xyzacExecutionWaitSamples = 0;
+    this.xyzacLastEnqueuedKinematicsMode = 0;
+    this.xyzacDeferredPhysicalSwitchMode = null;
+    this.xyzacDeferredBlockedActiveId = 0;
+    this.xyzacDeferredControlMotionType = 0;
+    this.xyzacQueuedLookaheadTargetId = 0;
+    this.xyzacAllowQueuedLookahead = false;
+    this.xyzacLastServoActiveId = 0;
+    this.xyzacLastQueuedMotion = null;
+    this.xyzacDeferredPhysicalPose = null;
+    this.xyzacDeferredPhysicalPoseApplied = false;
+    this.xyzacAppendDeferredOnActive = false;
+    this.xyzacDeferredCompletionActiveId = 0;
    this.motionAuthority = "js";
    this.task = new SimTask(core, { contextId, sessionId: sessionId || null });
    this.scheduler = new SimScheduler(core);
@@ -149,13 +172,14 @@ export class SimSession {
    // WASM pose samples into every 10 ms step response; the frontend retains
    // the canonical path from PROGRAM_LOAD/PROGRAM_RESTART.
    const lightweightXyzacStep = input.kind === "SIM_STEP" && Boolean(this.xyzacProgram);
-    const currentMotion = this.wasmMotion.read();
+    const traceOnlyStep = lightweightXyzacStep && input.payload?.trace_only === true;
+    const currentMotion = traceOnlyStep && statePayload.wasm_motion ? statePayload.wasm_motion : this.wasmMotion.read();
    const completedMotion = program.status === 4 && currentMotion.state?.queue_depth === 0;
    // Compact payloads are only valid for successful motion samples. Error
    // responses must retain their code/reason instead of being rewritten into
    // a delta with undefined fields.
    const motionDelta = kind === "COMMAND_RESULT" && lightweightXyzacStep && input.payload?.response === "motion_delta" && !completedMotion;
-    const panelSnapshot = motionDelta ? null : this.panelSnapshot({ task, program, input, tick, motionTrace: statePayload.motion_trace, includeToolpath: !lightweightXyzacStep, includeConfiguration: !lightweightXyzacStep, includeStableRuntime: !lightweightXyzacStep });
+    const panelSnapshot = motionDelta || traceOnlyStep ? null : this.panelSnapshot({ task, program, input, tick, motionTrace: statePayload.motion_trace, includeToolpath: !lightweightXyzacStep, includeConfiguration: !lightweightXyzacStep, includeStableRuntime: !lightweightXyzacStep });
    const compactProgram = motionDelta ? {
      schema: program.schema,
      source: program.source,
@@ -208,7 +232,7 @@ export class SimSession {
        motion_authority: responsePayload.motion_authority ?? this.motionAuthority,
        task_authority: responsePayload.task_authority ?? this.task.authority(),
        ...(!lightweightXyzacStep ? { wasm_home_limit: statePayload.wasm_home_limit ?? this.wasmHomeLimit.read() } : {}),
-        axis_state: axisState({ task, program, motion: this.motionProjection(), devices: {}, io: this.xyzacIo?.canonical?.() ?? {}, device_io: this.xyzacDeviceIo?.canonical?.() ?? this.deviceIo.export(), action: input.kind, payload: input.payload ?? {} }),
+        ...(traceOnlyStep ? {} : { axis_state: axisState({ task, program, motion: this.motionProjection(), devices: {}, io: this.xyzacIo?.canonical?.() ?? {}, device_io: this.xyzacDeviceIo?.canonical?.() ?? this.deviceIo.export(), action: input.kind, payload: input.payload ?? {} }) }),
      },
    };
  }
@@ -220,10 +244,11 @@ export class SimSession {
    const io = this.xyzacIo?.canonical?.();
    const ioState = io && typeof io === "object" && io.status !== "blocked" ? io : null;
    const kinematics = this.xyzacKinematics?.snapshot?.();
-    const kinematicsJoints = kinematics?.joints?.length === 5 ? [...kinematics.joints] : null;
+    const plannerJoints = wasmMotion.status === "verified" && Array.isArray(wasmMotion.state.joint_commanded) && wasmMotion.state.joint_commanded.length === 5 ? [...wasmMotion.state.joint_commanded] : null;
+    const kinematicsJoints = plannerJoints ?? (kinematics?.joints?.length === 5 ? [...kinematics.joints] : null);
    const unsigned = {
      schema: "sim_motion.v1",
-      source: "wasm_motion_queue",
+      source: wasmMotion.state.source ?? "wasm_motion_queue",
      tick: wasmMotion.status === "verified" ? wasmMotion.state.tick : this.tick,
      axes: { x: position.x, y: position.y, z: position.z },
      joints: kinematicsJoints ?? (home.status === "verified" && Array.isArray(home.state.joints) ? [...home.state.joints] : [position.x, position.y, position.z, position.a ?? 0, position.c ?? 0]),
@@ -269,7 +294,7 @@ export class SimSession {
      const path = `${basePath.replace(/\/demos$/, "")}/${suffix}`;
      const source = this.workspaceFiles[path];
      if (typeof source !== "string") return { status: "error", code: "program_subroutine_missing", path };
-      const added = this.xyzacProgram.addSubroutine(name, source);
+      const added = this.xyzacProgram.addSubroutine(name, source, path);
      if (added.status !== "verified") return added;
    }
    return { status: "verified", count: rows.length };
@@ -803,7 +828,10 @@ export class SimSession {
    let replayHomeLimit = null;
    try {
      if (replayMotionAuthority === "wasm") {
-        replayWasmMotion = new WasmMotionQueue(this.core);
+        replayWasmMotion = new WasmMotionQueue(this.core, {
+          cycleTime: Number(checkpoint.state.wasm_motion.cycle_time ?? this.xyzacMotionCycleTime),
+          velocityLimit: Number(checkpoint.state.wasm_motion.velocity_limit ?? 1e9),
+        });
        replayWasmMotion.restoreState(checkpoint.state.wasm_motion);
        if (checkpoint.state.wasm_home_limit) {
          replayHomeLimit = new WasmHomeLimit(this.core);
@@ -1154,6 +1182,23 @@ export class SimSession {
        // interpreter command and trajectory, then leave the taskfile loaded
        // for a later AUTO run after ESTOP_RESET and POWER ON.
        this.xyzacProgram.abort();
+        this.pendingXyzacMotion = null;
+        this.pendingProgramControl = 0;
+        this.pendingTaskSync = 0;
+        this.pendingServoSync = 0;
+        this.xyzacExecutionWaitNextMotion = false;
+        this.xyzacExecutionWaitSamples = 0;
+        this.xyzacLastEnqueuedKinematicsMode = 0;
+        this.xyzacDeferredPhysicalSwitchMode = null;
+        this.xyzacDeferredBlockedActiveId = 0;
+        this.xyzacDeferredControlMotionType = 0;
+        this.xyzacQueuedLookaheadTargetId = 0;
+        this.xyzacAllowQueuedLookahead = false;
+        this.xyzacLastServoActiveId = 0;
+        this.xyzacLastQueuedMotion = null;
+        this.xyzacDeferredPhysicalPose = null;
+        this.xyzacDeferredPhysicalPoseApplied = false;
+        this.xyzacAppendDeferredOnActive = false;
        this.wasmMotion.abort();
        this.wasmMotion.setPaused(true);
        const resetProgram = this.resetXyzacProgramToLoaded();
@@ -1240,6 +1285,23 @@ export class SimSession {
              /* LinuxCNC emcTaskSetState(OFF) aborts motion, clears the
                 interpreter command and leaves the loaded taskfile intact. */
              this.xyzacProgram.abort();
+              this.pendingXyzacMotion = null;
+              this.pendingProgramControl = 0;
+              this.pendingTaskSync = 0;
+              this.pendingServoSync = 0;
+              this.xyzacExecutionWaitNextMotion = false;
+              this.xyzacExecutionWaitSamples = 0;
+              this.xyzacLastEnqueuedKinematicsMode = 0;
+              this.xyzacDeferredPhysicalSwitchMode = null;
+              this.xyzacDeferredBlockedActiveId = 0;
+              this.xyzacDeferredControlMotionType = 0;
+              this.xyzacQueuedLookaheadTargetId = 0;
+              this.xyzacAllowQueuedLookahead = false;
+              this.xyzacLastServoActiveId = 0;
+              this.xyzacLastQueuedMotion = null;
+              this.xyzacDeferredPhysicalPose = null;
+              this.xyzacDeferredPhysicalPoseApplied = false;
+              this.xyzacAppendDeferredOnActive = false;
              this.wasmMotion.abort();
              this.wasmMotion.setPaused(true);
              const resetProgram = this.resetXyzacProgramToLoaded();
@@ -1348,9 +1410,24 @@ export class SimSession {
          this.xyzacDeviceIo?.destroy();
          this.xyzacDeviceIo = new WasmXyzacDeviceIo(this.core, { encoderCount: 2 });
          this.xyzacProgram?.destroy();
+          this.wasmMotion.destroy();
+          this.xyzacMotionCycleTime = Number(configuration.kinematics?.servo_cycle_time ?? configuration.kinematics?.cycle_time ?? 0.01);
+          if (!Number.isFinite(this.xyzacMotionCycleTime) || this.xyzacMotionCycleTime <= 0) throw new Error("wasm_xyzac_cycle_time_invalid");
+          const taskCycleTime = Number(configuration.kinematics?.task_cycle_time ?? this.xyzacMotionCycleTime);
+          this.xyzacTaskCycleTicks = Math.max(1, Math.round(taskCycleTime / this.xyzacMotionCycleTime));
+          this.wasmMotion = this.planner === "linuxcnc-tp"
+            ? new WasmLinuxcncTp(this.core, { cycleTime: this.xyzacMotionCycleTime, velocityLimit: this.xyzacRapidVelocity, accelerationLimit: Number(configuration.kinematics?.max_acceleration ?? 300) })
+            : new WasmMotionQueue(this.core, { cycleTime: this.xyzacMotionCycleTime, velocityLimit: 1e9 });
          this.xyzacProgram = new WasmProgramRuntime(this.core);
          this.xyzacProgramKinematicsMode = XYZAC_MODES.identity;
+          if (typeof this.wasmMotion.setKinematics === "function") this.wasmMotion.setKinematics(this.xyzacKinematics);
          this.xyzacRapidVelocity = Number(configuration.kinematics?.max_linear_velocity ?? 35);
+          const linearLimit = Number(configuration.kinematics?.axis_linear_velocity_limit ?? 20);
+          const angularLimit = Number(configuration.kinematics?.axis_angular_velocity_limit ?? 30);
+          this.xyzacAxisVelocityLimits = { x: linearLimit, y: linearLimit, z: linearLimit, a: angularLimit, c: angularLimit };
+          const accelerationLimit = Number(configuration.kinematics?.max_acceleration ?? 300);
+          this.xyzacAxisAccelerationLimits = { x: accelerationLimit, y: accelerationLimit, z: accelerationLimit, a: accelerationLimit, c: accelerationLimit };
+          this.wasmMotion.setDynamics(Number(configuration.kinematics?.max_acceleration ?? 300), Number(configuration.kinematics?.max_jerk ?? 1000000000));
          this.xyzacProgram.setRapidVelocity(this.xyzacRapidVelocity);
        }
        if (configuration?.home_limits && this.motionAuthority === "wasm") {
@@ -1414,54 +1491,152 @@ export class SimSession {
        if (limit.status !== "accepted") return finish(this.envelope("ERROR", input, { ...limit, operation_id: input.operation_id ?? null, simulation_tick: this.tick, retryable: false }), "failed");
        let program_steps = [];
        const motion_trace = [];
+        let sourceLookaheadReady = false;
        try {
          this.scheduler.step(cycles, {
-          task: () => {
+          task: (nextTick) => {
              if (this.xyzacProgram) {
                const wasmState = this.xyzacProgram.snapshot();
                if (![2, 3].includes(wasmState.status)) return;
+                if (this.pendingTaskSync !== 0) {
+                  this.pendingTaskSync = 0;
+                  return;
+                }
                // LinuxCNC's task/interpreter blocks on a full trajectory
                // planner queue. Let the motion phase consume one segment
                // before reading another source line instead of converting
                // normal planner backpressure into a program fault.
                if (this.wasmMotion.read().state.queue_depth >= this.wasmMotion.queueCapacity) return;
+                if (this.pendingXyzacMotion) {
+                  const pendingMode = Number(this.pendingXyzacMotion.kinematics_mode ?? 0);
+                  if (this.xyzacAppendDeferredOnActive) return;
+                  const queueState = this.wasmMotion.read().state;
+                  const deferredControlReady = this.xyzacDeferredControlMotionType === 1
+                    ? Number(queueState.active_id ?? 0) !== this.xyzacDeferredBlockedActiveId
+                    : Number(queueState.active_id ?? 0) === this.xyzacDeferredBlockedActiveId;
+                  const deferredSwitchMotion = this.xyzacDeferredPhysicalSwitchMode !== null && pendingMode === this.xyzacDeferredPhysicalSwitchMode && this.xyzacQueuedLookaheadTargetId === 0 && deferredControlReady;
+                  const queuedLookaheadReady = deferredSwitchMotion || (this.xyzacAllowQueuedLookahead && this.xyzacLastServoActiveId === this.xyzacQueuedLookaheadTargetId);
+                  if (queueState.queue_depth !== 0 && !queuedLookaheadReady) return;
+                  if (queuedLookaheadReady && !deferredSwitchMotion && this.xyzacAllowQueuedLookahead) {
+                    // The next segment is appended after the first servo
+                    // sample of the now-active target, matching LinuxCNC's
+                    // TP queue observation (q=1 on entry, q=2 thereafter).
+                    sourceLookaheadReady = true;
+                    return;
+                  }
+                  const pending = this.pendingXyzacMotion;
+                  this.pendingXyzacMotion = null;
+                  const enqueue = this.wasmMotion.enqueue(pending);
+                  if (enqueue.status === "error") throw new Error(enqueue.code);
+                  const modeChanged = pendingMode !== this.xyzacLastEnqueuedKinematicsMode;
+                  this.xyzacLastEnqueuedKinematicsMode = pendingMode;
+                  this.xyzacLastQueuedMotion = pending;
+                  if (this.planner === "linuxcnc-tp" && modeChanged && queueState.queue_depth !== 0) {
+                    this.xyzacAllowQueuedLookahead = true;
+                    this.xyzacQueuedLookaheadTargetId = Number(pending.source_line ?? 0);
+                  }
+                  if (queuedLookaheadReady && !modeChanged) {
+                    this.xyzacAllowQueuedLookahead = false;
+                    this.xyzacQueuedLookaheadTargetId = 0;
+                  }
+                  if (this.xyzacExecutionWaitNextMotion && pendingMode !== XYZAC_MODES.identity) {
+                    this.xyzacExecutionWaitNextMotion = false;
+                    this.xyzacExecutionWaitSamples = 1;
+                  } else if (pendingMode === XYZAC_MODES.identity) this.xyzacExecutionWaitNextMotion = false;
+                  if (this.planner !== "linuxcnc-tp" || !modeChanged || queueState.queue_depth !== 0) return;
+                  // Source TP performs one servo cycle on the newly active
+                  // segment before task lookahead appends the next XYZAC
+                  // segment. Keep parsing in this task, but defer that queue
+                  // mutation until the first servo sample below.
+                  sourceLookaheadReady = true;
+                }
+                // LinuxCNC's task planner consumes non-motion interpreter
+                // blocks in the same task cycle and stops when the first
+                // canonical motion is handed to TP. Preserve that boundary
+                // instead of charging comments, parameter assignments, M429,
+                // and G10 blocks as artificial motion ticks.
+                for (let parserStep = 0; parserStep < 64; parserStep += 1) {
                if (this.pendingProgramControl !== 0) {
-                  if (this.wasmMotion.read().state.queue_depth !== 0) return;
-                  const current = this.wasmMotion.read().state.position;
-                  this.xyzacProgramKinematicsMode = { 428: XYZAC_MODES.xyzac, 429: XYZAC_MODES.identity, 430: XYZAC_MODES.userk }[this.pendingProgramControl];
-                  const selected = this.xyzacKinematics.select(this.xyzacProgramKinematicsMode, [current.x, current.y, current.z, current.a ?? 0, current.c ?? 0]);
-                  if (selected.status !== "verified") throw new Error(`wasm_switchkins_control_${this.pendingProgramControl}`);
-                  this.pendingProgramControl = 0;
-                  return;
-                }
-                const step = this.xyzacProgram.step();
-                if (step.status !== "verified") throw new Error(step.code);
-                // Path control is produced by the WASM interpreter and applied
-                // to the WASM trajectory queue before the block's motion is
-                // enqueued.  G61/G61.1 conservatively use the queue's exact
-                // profile; G64 restores the continuous lookahead profile.
-                const motionControlMode = Number(step.program?.motion_control_mode ?? 0);
-                const queueProfile = motionControlMode === 0 ? 0 : 1;
-                if (this.wasmMotion.controls.profile !== queueProfile) this.wasmMotion.setProfile(queueProfile);
-                if (step.has_control && [428, 429, 430].includes(step.control_code)) {
-                  this.pendingProgramControl = step.control_code;
-                  if (this.wasmMotion.read().state.queue_depth === 0) {
-                    const current = this.wasmMotion.read().state.position;
-                    this.xyzacProgramKinematicsMode = { 428: XYZAC_MODES.xyzac, 429: XYZAC_MODES.identity, 430: XYZAC_MODES.userk }[step.control_code];
-                    const selected = this.xyzacKinematics.select(this.xyzacProgramKinematicsMode, [current.x, current.y, current.z, current.a ?? 0, current.c ?? 0]);
-                    if (selected.status !== "verified") throw new Error(`wasm_switchkins_control_${step.control_code}`);
+                    const pendingControl = this.pendingProgramControl;
+                    const queueState = this.wasmMotion.read().state;
+                    const deferIdentitySwitch = pendingControl === 429 && this.planner === "linuxcnc-tp" && (Number(queueState.motion_type ?? 0) === 3 || (Number(queueState.motion_type ?? 0) === 1 && Number(queueState.progress ?? 0) >= 0.999999));
+                    if (queueState.queue_depth !== 0 && !deferIdentitySwitch) return;
+                    if (queueState.queue_depth !== 0 && deferIdentitySwitch) {
+                      this.xyzacProgramKinematicsMode = XYZAC_MODES.identity;
+                      this.xyzacDeferredPhysicalSwitchMode = XYZAC_MODES.identity;
+                      this.xyzacDeferredBlockedActiveId = Number(queueState.active_id ?? 0);
+                      this.xyzacDeferredControlMotionType = Number(queueState.motion_type ?? 0);
+                      const queuedEnd = this.xyzacLastQueuedMotion?.end ?? queueState.position;
+                      const endInverse = this.xyzacKinematics.inverseMode(XYZAC_MODES.xyzac, queuedEnd);
+                      if (endInverse.status !== "verified") throw new Error(`wasm_switchkins_deferred_inverse_${endInverse.code ?? "error"}`);
+                      const physical = this.xyzacKinematics.selectPhysical(XYZAC_MODES.identity, endInverse.joints);
+                      if (physical.status !== "verified") throw new Error(`wasm_switchkins_deferred_${physical.code ?? "error"}`);
+                      if (typeof this.wasmMotion.setGoalPosition === "function" && physical.pose) this.wasmMotion.setGoalPosition(physical.pose);
+                      this.xyzacDeferredPhysicalPose = physical.pose;
+                      this.xyzacDeferredPhysicalPoseApplied = false;
+                      this.xyzacDeferredCompletionActiveId = Number(this.xyzacLastQueuedMotion?.source_line ?? 0);
+                      // Preparing the future identity goal must not switch
+                      // the active kinematics while the helix is running.
+                      const restored = this.xyzacKinematics.selectPhysical(XYZAC_MODES.xyzac, endInverse.joints);
+                      if (restored.status !== "verified") throw new Error(`wasm_switchkins_deferred_restore_${restored.code ?? "error"}`);
+                      this.pendingProgramControl = 0;
+                      this.pendingTaskSync = 0;
+                      continue;
+                    }
+                    const currentState = this.wasmMotion.read().state;
+                    const current = currentState.position;
+                    this.xyzacProgramKinematicsMode = { 428: XYZAC_MODES.xyzac, 429: XYZAC_MODES.identity, 430: XYZAC_MODES.userk }[pendingControl];
+                    const joints = Array.isArray(currentState.joint_commanded) && currentState.joint_commanded.length === 5
+                      ? currentState.joint_commanded
+                      : [current.x, current.y, current.z, current.a ?? 0, current.c ?? 0];
+                    const selected = typeof this.xyzacKinematics.selectPhysical === "function"
+                      ? this.xyzacKinematics.selectPhysical(this.xyzacProgramKinematicsMode, joints)
+                      : this.xyzacKinematics.select(this.xyzacProgramKinematicsMode, joints);
+                    if (selected.status !== "verified") throw new Error(`wasm_switchkins_control_${this.pendingProgramControl}`);
+                    if (this.planner === "linuxcnc-tp" && selected.pose) {
+                      this.wasmMotion.setPosition(selected.pose);
+                      if (typeof this.wasmMotion.setActiveKinematicsTag === "function") this.wasmMotion.setActiveKinematicsTag(this.xyzacProgramKinematicsMode);
+                    }
                    this.pendingProgramControl = 0;
+                    if (this.planner === "linuxcnc-tp" && pendingControl === 428) this.xyzacExecutionWaitNextMotion = true;
                  }
-                }
-                const steps = step.motion ? [step] : [];
-                program_steps.push(step);
-                for (const item of steps) {
-                  item.motion.kinematics_mode = this.xyzacProgramKinematicsMode;
-                  const linearNoop = item.motion.motion_type === 1 && ["x", "y", "z", "a", "b", "c", "u", "v", "w"].every((axis) => item.motion.start[axis] === item.motion.end[axis]);
-                  if (!linearNoop) {
-                    const enqueue = this.wasmMotion.enqueue(item.motion);
-                    if (enqueue.status === "error") throw new Error(enqueue.code);
+                  const step = this.xyzacProgram.step();
+                  if (step.status !== "verified") throw new Error(step.code);
+                  // Path control is produced by the WASM interpreter and
+                  // applied to the WASM trajectory queue before enqueue.
+                  const motionControlMode = Number(step.program?.motion_control_mode ?? 0);
+                  if (typeof this.wasmMotion.setTermCondition === "function") {
+                    const mode = motionControlMode === 0 ? "continuous" : motionControlMode === 1 ? "exact_path" : "exact_stop";
+                    this.wasmMotion.setTermCondition(mode, Number(step.program?.path_tolerance ?? 0));
+                  } else {
+                    const queueProfile = motionControlMode === 0 ? 0 : 1;
+                    if (this.wasmMotion.controls.profile !== queueProfile) this.wasmMotion.setProfile(queueProfile);
                  }
+                  program_steps.push(step);
+                  if (step.has_control && [428, 429, 430].includes(step.control_code)) {
+                    this.pendingProgramControl = step.control_code;
+                    if (this.planner === "linuxcnc-tp") this.pendingTaskSync = 1;
+                  }
+                  if (step.motion) {
+                    step.motion.kinematics_mode = this.xyzacProgramKinematicsMode;
+                    step.motion.source_line = Number(step.program?.execution_source_line ?? step.line ?? step.motion.source_line ?? 0);
+                    step.motion.source_file = step.program?.execution_source_file ?? this.xyzacProgram.path;
+                    const linearNoop = step.motion.motion_type === 1 && ["x", "y", "z", "a", "b", "c", "u", "v", "w"].every((axis) => step.motion.start[axis] === step.motion.end[axis]);
+                    if (!linearNoop) {
+                      // Commands issued by task become visible to motion on
+                      // the following task cycle, matching LinuxCNC's NML
+                      // handoff boundary and preventing a zero-time jump in
+                      // current_line/exec_state snapshots.
+                      const directDeferredMotion = this.planner === "linuxcnc-tp" && this.xyzacDeferredPhysicalSwitchMode !== null && this.xyzacDeferredControlMotionType === 1 && Number(step.motion.kinematics_mode ?? 0) === XYZAC_MODES.identity;
+                      this.pendingXyzacMotion = step.motion;
+                      if (directDeferredMotion) {
+                        this.xyzacAppendDeferredOnActive = true;
+                        if (typeof this.wasmMotion.setQueueDepthOverride === "function") this.wasmMotion.setQueueDepthOverride(2);
+                      }
+                    }
+                    return;
+                  }
+                  if (step.program?.status === 4) return;
                }
                return;
              }
@@ -1496,17 +1671,72 @@ export class SimSession {
              this.task.setTick(nextTick);
              const xyzacAuthority = Boolean(this.xyzacProgram);
              const motionState = xyzacAuthority ? null : this.motion.step(nextTick);
-              const wasmMotion = this.wasmMotion.step();
-              if (wasmMotion.status === "error" && wasmMotion.code !== "wasm_motion_step_-605") throw new Error(wasmMotion.code);
+              // The selected LinuxCNC case has a 1 ms servo period and a
+              // 10 ms task period. A public SIM_STEP represents one task
+              // cycle, so advance the WASM motion queue by the configured
+              // servo/task ratio while publishing one stable task snapshot.
+              let wasmMotion = this.wasmMotion.read();
+              for (let servo = 0; servo < this.xyzacTaskCycleTicks; servo += 1) {
+                if (this.planner === "linuxcnc-tp" && typeof this.wasmMotion.setExecutionState === "function") {
+                  this.wasmMotion.setExecutionState(this.xyzacExecutionWaitSamples > 0 ? 2 : 3);
+                }
+                const queueBeforeServo = Number(typeof this.wasmMotion.queueDepth === "function" ? this.wasmMotion.queueDepth() : this.wasmMotion.read().state.queue_depth ?? 0);
+                const beforeServoState = this.wasmMotion.read().state;
+                let servoResult;
+                servoResult = this.wasmMotion.step();
+                if (servoResult.status === "error" && servoResult.code !== "wasm_motion_step_-605") throw new Error(servoResult.code);
+                if (servoResult.status === "verified") {
+                  wasmMotion = servoResult;
+                  this.xyzacLastServoActiveId = Number(servoResult.state.active_id ?? 0);
+                  const queuedEndpoint = this.xyzacLastQueuedMotion?.end;
+                  const endpointNear = queuedEndpoint && Math.abs(Number(beforeServoState.position?.x ?? 0) - Number(queuedEndpoint.x ?? 0)) < 1e-3 && Math.abs(Number(beforeServoState.position?.y ?? 0) - Number(queuedEndpoint.y ?? 0)) < 1e-3 && Math.abs(Number(beforeServoState.position?.z ?? 0) - Number(queuedEndpoint.z ?? 0)) < 1e-3;
+                  if (this.xyzacAppendDeferredOnActive && this.pendingXyzacMotion && Number(beforeServoState.active_id ?? 0) === this.xyzacDeferredCompletionActiveId && Number(beforeServoState.motion_type ?? 0) === 3 && (Number(beforeServoState.progress ?? 0) >= 0.999999 || (Number(beforeServoState.velocity ?? 0) <= 0.1 && endpointNear))) {
+                    if (!this.xyzacDeferredPhysicalPoseApplied && this.xyzacDeferredPhysicalPose) {
+                      this.wasmMotion.setPosition(this.xyzacDeferredPhysicalPose);
+                      this.xyzacDeferredPhysicalPoseApplied = true;
+                    }
+                    const deferredMotion = this.pendingXyzacMotion;
+                    const deferredEnqueue = this.wasmMotion.enqueue(deferredMotion);
+                    if (deferredEnqueue.status === "error") throw new Error(deferredEnqueue.code);
+                    this.xyzacLastEnqueuedKinematicsMode = Number(deferredMotion.kinematics_mode ?? 0);
+                    this.xyzacLastQueuedMotion = deferredMotion;
+                    this.xyzacAllowQueuedLookahead = true;
+                    this.xyzacQueuedLookaheadTargetId = Number(deferredMotion.source_line ?? 0);
+                    this.pendingXyzacMotion = null;
+                    this.xyzacAppendDeferredOnActive = false;
+                    if (typeof this.wasmMotion.setQueueDepthOverride === "function") this.wasmMotion.setQueueDepthOverride(null);
+                    servoResult.state.queue_depth = 2;
+                    if (Array.isArray(this.wasmMotion.history) && this.wasmMotion.history.length) this.wasmMotion.history[this.wasmMotion.history.length - 1].queue_depth = 2;
+                  }
+                  if (this.planner === "linuxcnc-tp" && this.xyzacExecutionWaitSamples > 0 && Number(servoResult.state.active_id ?? 0) !== 0) this.xyzacExecutionWaitSamples -= 1;
+                  if (this.planner === "linuxcnc-tp" && this.xyzacDeferredPhysicalSwitchMode !== null && Number(servoResult.state.active_tag ?? -1) === this.xyzacDeferredPhysicalSwitchMode) {
+                    const physicalJoints = Array.isArray(servoResult.state.joint_commanded) ? servoResult.state.joint_commanded : [];
+                    const physical = this.xyzacKinematics.selectPhysical(this.xyzacDeferredPhysicalSwitchMode, physicalJoints);
+                    if (physical.status !== "verified") throw new Error(`wasm_switchkins_deferred_${physical.code ?? "error"}`);
+                    this.xyzacDeferredPhysicalSwitchMode = null;
+                    this.xyzacDeferredPhysicalPose = null;
+                    this.xyzacDeferredPhysicalPoseApplied = false;
+                  }
+                  if (this.planner === "linuxcnc-tp" && sourceLookaheadReady && servo === 0 && this.pendingXyzacMotion) {
+                    const lookaheadMode = Number(this.pendingXyzacMotion.kinematics_mode ?? 0);
+                    const lookahead = this.wasmMotion.enqueue(this.pendingXyzacMotion);
+                    if (lookahead.status === "error") throw new Error(lookahead.code);
+                    this.xyzacLastEnqueuedKinematicsMode = lookaheadMode;
+                    this.xyzacLastQueuedMotion = this.pendingXyzacMotion;
+                    this.pendingXyzacMotion = null;
+                    this.xyzacAllowQueuedLookahead = false;
+                    this.xyzacQueuedLookaheadTargetId = 0;
+                    sourceLookaheadReady = false;
+                    wasmMotion = this.wasmMotion.read();
+                  }
+                }
+              }
              if (motionState?.fault && this.task.state.state === "RUNNING") this.task.fault(-1205);
              if (this.motionAuthority === "wasm") {
                if (wasmMotion.status === "verified") {
                  if (!xyzacAuthority) {
                    const position = this.motion.applyWasmPosition(wasmMotion.state.position, wasmMotion.state.velocity, nextTick);
                    if (position.status === "error") throw new Error(position.code);
-                  } else if (this.xyzacKinematics && wasmMotion.state.active_id !== 0 && this.xyzacProgramKinematicsMode !== XYZAC_MODES.identity) {
-                    const inverse = this.xyzacKinematics.inverse(wasmMotion.state.position);
-                    if (inverse.status !== "verified") throw new Error(`wasm_xyzac_motion_inverse_${inverse.code ?? "error"}`);
                  }
                }
                if (xyzacAuthority) {
@@ -1561,12 +1791,12 @@ export class SimSession {
          .filter((entry) => Number.isSafeInteger(entry.line) && entry.line > 0);
        if (program) {
          const status = this.xyzacProgram ? (program.status === 4 ? "completed" : program.status === 2 ? "running" : program.status === 3 ? "paused" : "loaded") : (program.program_status === "completed" ? "completed" : program.program_status === "running" ? "running" : program.program_status);
-          this.task.setProgram(status, this.xyzacProgram ? program.current_line : program.line);
+          this.task.setProgram(status, this.xyzacProgram ? (program.execution_source_line ?? program.current_line) : program.line);
          if (status === "completed" && this.task.state.state === "RUNNING" && (this.motionAuthority !== "wasm" || this.wasmMotion.read().state.queue_depth === 0)) this.task.transition("STOPPED");
        }
-        const snapshotState = { tick: this.tick, cycles, motion_authority: this.motionAuthority, task: this.task.export(), scheduler: this.scheduler.export(), authoritative: this.xyzacProgram ? { schema: "wasm_authority_boundary.v1", source: "linuxcnc-wasm-worker" } : this.authoritative.export(), wasm_motion: this.wasmMotion.read(), motion: this.motionProjection(), plc: this.plc.export(), hal_runtime: this.xyzacIo ? this.xyzacIo.halExport() : this.hal.export(), device_io: this.xyzacDeviceIo ? this.xyzacDeviceIo.export() : this.xyzacIo ? this.xyzacIo.export() : this.deviceIo.export(), configuration_batch: this.configurationBatch.export(), io_ack: this.ioAck.export(), callbacks: this.callbacks.export() };
+        const snapshotState = { tick: this.tick, cycles, motion_authority: this.motionAuthority, task: this.task.export(), scheduler: this.scheduler.export(), authoritative: this.xyzacProgram ? { schema: "wasm_authority_boundary.v1", source: "linuxcnc-wasm-worker" } : this.authoritative.export(), wasm_motion: this.wasmMotion.read(), motion: this.motionProjection(), plc: this.plc.export(), hal_runtime: this.xyzacIo ? this.xyzacIo.halExport() : this.hal.export(), device_io: this.xyzacDeviceIo ? this.xyzacDeviceIo.export() : this.xyzacIo ? this.xyzacIo.export() : this.deviceIo.export(), configuration_batch: this.configurationBatch.export(), io_ack: this.ioAck.export(), callbacks: this.callbacks.export(), xyzac_timing: { servo_cycle_time: this.xyzacMotionCycleTime, task_cycle_ticks: this.xyzacTaskCycleTicks } };
        if (program) snapshotState.program = program;
-        const snapshot = this.timeline.checkpoint(input.seq, this.tick, snapshotState, this.timeline.snapshots.latest()?.snapshot_id ?? null);
+        const snapshot = input.payload?.trace_only === true ? null : this.timeline.checkpoint(input.seq, this.tick, snapshotState, this.timeline.snapshots.latest()?.snapshot_id ?? null);
        const lightweightXyzac = Boolean(this.xyzacProgram);
        return finish(this.envelope("COMMAND_RESULT", input, {
          status: "verified", cycles, program_steps, execution_trace,
@@ -1574,14 +1804,31 @@ export class SimSession {
          motion_authority: this.motionAuthority,
          task: this.task.export(), scheduler: this.scheduler.export(), authoritative: snapshotState.authoritative,
          wasm_motion: this.wasmMotion.read(), motion: snapshotState.motion,
-          ...(lightweightXyzac ? {} : { plc: this.plc.export(), hal_runtime: snapshotState.hal_runtime, device_io: snapshotState.device_io, configuration_batch: this.configurationBatch.export(), io_ack: this.ioAck.export(), callbacks: this.callbacks.export(), snapshot }),
-          ...(program ? { program } : {}), state_hash: snapshot.state_hash,
+          ...(lightweightXyzac ? {} : { plc: this.plc.export(), hal_runtime: snapshotState.hal_runtime, device_io: snapshotState.device_io, configuration_batch: this.configurationBatch.export(), io_ack: this.ioAck.export(), callbacks: this.callbacks.export(), ...(snapshot ? { snapshot } : {}) }),
+          ...(program ? { program } : {}), state_hash: snapshot?.state_hash ?? fnv1a64(snapshotState),
        }));
      }
      case "PROGRAM_LOAD": {
        if (["RUNNING", "PAUSED"].includes(this.task.state.state)) return finish(this.error(input, "task_state", "program_load_while_active"), "failed");
        const source = input.payload?.source ?? input.payload?.text ?? input.payload?.program_source;
        if (this.xyzacProgram) {
+          this.pendingXyzacMotion = null;
+          this.pendingProgramControl = 0;
+          this.pendingTaskSync = 0;
+          this.pendingServoSync = 0;
+          this.xyzacExecutionWaitNextMotion = false;
+          this.xyzacExecutionWaitSamples = 0;
+          this.xyzacLastEnqueuedKinematicsMode = 0;
+          this.xyzacDeferredPhysicalSwitchMode = null;
+          this.xyzacDeferredBlockedActiveId = 0;
+          this.xyzacDeferredControlMotionType = 0;
+          this.xyzacQueuedLookaheadTargetId = 0;
+          this.xyzacAllowQueuedLookahead = false;
+          this.xyzacLastServoActiveId = 0;
+          this.xyzacLastQueuedMotion = null;
+          this.xyzacDeferredPhysicalPose = null;
+          this.xyzacDeferredPhysicalPoseApplied = false;
+          this.xyzacAppendDeferredOnActive = false;
          const result = this.xyzacProgram.load(source, input.payload?.path ?? null);
          if (result.status === "verified") this.xyzacProgram.setRapidVelocity(this.xyzacRapidVelocity);
          if (result.status === "verified") { const subroutines = this.loadXyzacSubroutines(input.payload?.path); if (subroutines.status !== "verified") return finish(this.error(input, "program_subroutine", subroutines.code), "failed"); }
@@ -1614,7 +1861,7 @@ export class SimSession {
      case "PROGRAM_RUN": {
        if (this.xyzacProgram) {
          const result = this.xyzacProgram.start();
-          if (result.status === "verified") { this.wasmMotion.setPaused(false); this.task.setMode("AUTO"); if (this.task.state.state === "STOPPED") this.task.recover(); this.task.transition("RUNNING"); this.task.setProgram("running", this.xyzacProgram.snapshot().current_line); }
+          if (result.status === "verified") { this.wasmMotion.setPaused(false); this.task.setMode("AUTO"); if (this.task.state.state === "STOPPED") this.task.recover(); this.task.transition("RUNNING"); const program = this.xyzacProgram.snapshot(); this.task.setProgram("running", program.execution_source_line ?? program.current_line); }
          return finish(this.envelope(result.status === "verified" ? "COMMAND_RESULT" : "ERROR", input, { ...result, program: this.xyzacProgram.snapshot(), task: this.task.export(), motion_authority: "wasm", command: input.kind, operation_id: input.operation_id ?? null }), result.status === "verified" ? "verified" : "failed");
        }
        const result = this.program.start();
@@ -1638,11 +1885,28 @@ export class SimSession {
      case "PROGRAM_PAUSE": case "PROGRAM_RESUME": case "PROGRAM_ABORT": {
        const action = input.kind === "PROGRAM_PAUSE" ? "pause" : input.kind === "PROGRAM_RESUME" ? "resume" : "abort";
        if (this.xyzacProgram) {
+          this.pendingXyzacMotion = null;
+          this.pendingProgramControl = 0;
+          this.pendingTaskSync = 0;
+          this.pendingServoSync = 0;
+          this.xyzacExecutionWaitNextMotion = false;
+          this.xyzacExecutionWaitSamples = 0;
+          this.xyzacLastEnqueuedKinematicsMode = 0;
+          this.xyzacDeferredPhysicalSwitchMode = null;
+          this.xyzacDeferredBlockedActiveId = 0;
+          this.xyzacDeferredControlMotionType = 0;
+          this.xyzacQueuedLookaheadTargetId = 0;
+          this.xyzacAllowQueuedLookahead = false;
+          this.xyzacLastServoActiveId = 0;
+          this.xyzacLastQueuedMotion = null;
+          this.xyzacDeferredPhysicalPose = null;
+          this.xyzacDeferredPhysicalPoseApplied = false;
+          this.xyzacAppendDeferredOnActive = false;
          const result = this.xyzacProgram[action]();
          if (result.status === "verified") {
-            if (action === "pause") { call(this.core, "sim_protocol_pause"); this.wasmMotion.setPaused(true); this.task.transition("PAUSED"); this.task.setProgram("paused", this.xyzacProgram.snapshot().current_line); }
-            else if (action === "resume") { call(this.core, "sim_protocol_resume"); this.wasmMotion.setPaused(false); this.task.transition("RUNNING"); this.task.setProgram("running", this.xyzacProgram.snapshot().current_line); }
-            else { this.wasmMotion.abort(); this.task.transition("STOPPED"); this.task.setProgram("aborted", this.xyzacProgram.snapshot().current_line); }
+            if (action === "pause") { call(this.core, "sim_protocol_pause"); this.wasmMotion.setPaused(true); this.task.transition("PAUSED"); const program = this.xyzacProgram.snapshot(); this.task.setProgram("paused", program.execution_source_line ?? program.current_line); }
+            else if (action === "resume") { call(this.core, "sim_protocol_resume"); this.wasmMotion.setPaused(false); this.task.transition("RUNNING"); const program = this.xyzacProgram.snapshot(); this.task.setProgram("running", program.execution_source_line ?? program.current_line); }
+            else { this.wasmMotion.abort(); this.task.transition("STOPPED"); const program = this.xyzacProgram.snapshot(); this.task.setProgram("aborted", program.execution_source_line ?? program.current_line); }
          }
          return finish(this.envelope(result.status === "verified" ? "COMMAND_RESULT" : "ERROR", input, { ...result, program: this.xyzacProgram.snapshot(), task: this.task.export(), motion_authority: "wasm", command: input.kind, operation_id: input.operation_id ?? null }), result.status === "verified" ? "verified" : "failed");
        }
@@ -1673,6 +1937,23 @@ export class SimSession {
      }
      case "PROGRAM_RESTART": {
        if (this.xyzacProgram) {
+          this.pendingXyzacMotion = null;
+          this.pendingProgramControl = 0;
+          this.pendingTaskSync = 0;
+          this.pendingServoSync = 0;
+          this.xyzacExecutionWaitNextMotion = false;
+          this.xyzacExecutionWaitSamples = 0;
+          this.xyzacLastEnqueuedKinematicsMode = 0;
+          this.xyzacDeferredPhysicalSwitchMode = null;
+          this.xyzacDeferredBlockedActiveId = 0;
+          this.xyzacDeferredControlMotionType = 0;
+          this.xyzacQueuedLookaheadTargetId = 0;
+          this.xyzacAllowQueuedLookahead = false;
+          this.xyzacLastServoActiveId = 0;
+          this.xyzacLastQueuedMotion = null;
+          this.xyzacDeferredPhysicalPose = null;
+          this.xyzacDeferredPhysicalPoseApplied = false;
+          this.xyzacAppendDeferredOnActive = false;
          const source = this.xyzacProgram.source;
          const result = this.xyzacProgram.load(source, this.xyzacProgram.path);
          if (result.status === "verified") this.xyzacProgram.setRapidVelocity(this.xyzacRapidVelocity);
--- a/web/worker/sim-worker.mjs
+++ b/web/worker/sim-worker.mjs
@@ -2,7 +2,7 @@ import createModule from "../../build-wasm/linuxcnc-sim-core.js";
 import { XyzacSession } from "./xyzac-session.mjs";

 const core = await createModule();
-const session = new XyzacSession(core);
+const session = new XyzacSession(core, { planner: "linuxcnc-tp" });

 self.onmessage = (event) => {
  try {
--- a/web/worker/wasm-linuxcnc-tp.mjs
+++ b/web/worker/wasm-linuxcnc-tp.mjs
@@ -0,0 +1,254 @@
+import { fnv1a64 } from "./replay.mjs";
+
+const POSE_BYTES = 72;
+const STATE_BYTES = 112;
+const SOURCE_TP_SCHEMA = "linuxcnc_source_tp_state.v1";
+
+function call(core, name, returnType, argTypes, args) {
+  const fn = core?.[`_${name}`] ?? core?.[name];
+  if (typeof fn === "function") return fn(...args);
+  if (typeof core?.ccall === "function") return core.ccall(name, returnType, argTypes, args);
+  throw new Error(`missing core export: ${name}`);
+}
+
+function poseArray(value = {}) { return ["x", "y", "z", "a", "b", "c", "u", "v", "w"].map((axis) => Number(value[axis] ?? 0)); }
+function toPose(values) { return Object.fromEntries(["x", "y", "z", "a", "b", "c", "u", "v", "w"].map((axis, index) => [axis, Number(values[index] ?? 0)])); }
+
+function cubicState() { return { x0: 0, x1: 0, x2: 0, x3: 0, t: 0, need: true, coeff: [0, 0, 0, 0] }; }
+function cubicAdd(state, point, segmentTime = 0.001) {
+  if (!state.need) return;
+  state.x0 = state.x1; state.x1 = state.x2; state.x2 = state.x3; state.x3 = Number(point);
+  const wp0 = (state.x0 + 4 * state.x1 + state.x2) / 6;
+  const wp1 = (state.x1 + 4 * state.x2 + state.x3) / 6;
+  const vel0 = (state.x2 - state.x0) / (2 * segmentTime);
+  const vel1 = (state.x3 - state.x1) / (2 * segmentTime);
+  const b = 3 * (wp1 - wp0) / (segmentTime * segmentTime) - (2 * vel0 + vel1) / segmentTime;
+  const a = (vel1 - vel0) / (3 * segmentTime * segmentTime) - 2 * b / (3 * segmentTime);
+  state.coeff = [a, b, vel0, wp0]; state.t = 0; state.need = false;
+}
+function cubicInterpolate(state, segmentTime = 0.001) {
+  if (state.need) cubicAdd(state, state.x3, segmentTime);
+  const [a, b, c, d] = state.coeff;
+  const t = state.t;
+  const value = ((a * t + b) * t + c) * t + d;
+  state.t += segmentTime;
+  if (Math.abs(segmentTime - state.t) < segmentTime * 0.5) state.need = true;
+  return value;
+}
+
+export class WasmLinuxcncTp {
+  constructor(core, { cycleTime = 0.001, velocityLimit = 35, accelerationLimit = 300 } = {}) {
+    this.core = core;
+    this.available = ["sim_linuxcnc_tp_size", "sim_linuxcnc_tp_init", "sim_linuxcnc_tp_read_state", "sim_linuxcnc_tp_step", "sim_linuxcnc_tp_idle", "sim_linuxcnc_tp_add_line", "sim_linuxcnc_tp_set_profile", "sim_linuxcnc_tp_set_feed_override", "sim_linuxcnc_tp_set_dynamics", "sim_linuxcnc_tp_set_paused", "sim_linuxcnc_tp_abort", "sim_linuxcnc_tp_set_goal_position", "sim_linuxcnc_tp_queue_depth", "sim_linuxcnc_tp_queue_segment", "sim_linuxcnc_tp_restore_progress"].every((name) => typeof core?.[`_${name}`] === "function" || typeof core?.[name] === "function");
+    this.cycleTime = cycleTime;
+    this.velocityLimit = velocityLimit;
+    this.accelerationLimit = accelerationLimit;
+    this.queueCapacity = 2000;
+    this.planner = 0;
+    this.posePointer = 0;
+    this.centerPointer = 0;
+    this.normalPointer = 0;
+    this.statePointer = 0;
+    this.history = [];
+    this.activeTag = 0;
+    this.segmentTags = new Map();
+    this.lastActiveId = 0;
+    // Task execution state is owned by the LinuxCNC task/TP handoff, not by
+    // the TP C struct. Keep it alongside the source-TP state so every servo
+    // sample carries the same WAITING_FOR_MOTION boundary as native LinuxCNC.
+    this.executionState = 3;
+    this.lastState = null;
+    this.queueDepthOverride = null;
+    this.kinematics = null;
+    this.cubic = Array.from({ length: 5 }, () => cubicState());
+    this.previousJointCommanded = [0, 0, 0, 0, 0];
+    this.controls = { profile: 0, lookahead: 50, acceleration_limit: accelerationLimit, jerk_limit: 1e9, feed_override: 1, paused: false };
+    if (!this.available || typeof core?._malloc !== "function") return;
+    this.planner = core._malloc(call(core, "sim_linuxcnc_tp_size", "number", [], []));
+    this.posePointer = core._malloc(POSE_BYTES);
+    this.centerPointer = core._malloc(24);
+    this.normalPointer = core._malloc(24);
+    this.statePointer = core._malloc(STATE_BYTES);
+    if (![this.planner, this.posePointer, this.centerPointer, this.normalPointer, this.statePointer].every(Boolean)) throw new Error("linuxcnc_tp_allocation_failed");
+    const result = call(core, "sim_linuxcnc_tp_init", "number", ["number", "number", "number", "number"], [this.planner, cycleTime, velocityLimit, accelerationLimit]);
+    if (result !== 0) throw new Error(`linuxcnc_tp_init_${result}`);
+    this.setPosition({ x: 0, y: 0, z: 0, a: 0, b: 0, c: 0, u: 0, v: 0, w: 0 });
+    this.setProfile(0);
+  }
+
+  setPosition(value) {
+    if (!this.available) return this.read();
+    this.core.HEAPF64.set(poseArray(value), this.posePointer / 8);
+    const result = call(this.core, "sim_linuxcnc_tp_set_position", "number", ["number", "number"], [this.planner, this.posePointer]);
+    if (result !== 0) throw new Error(`linuxcnc_tp_set_position_${result}`);
+    return this.read();
+  }
+
+  setGoalPosition(value) {
+    if (!this.available) return this.read();
+    this.core.HEAPF64.set(poseArray(value), this.posePointer / 8);
+    const result = call(this.core, "sim_linuxcnc_tp_set_goal_position", "number", ["number", "number"], [this.planner, this.posePointer]);
+    if (result !== 0) throw new Error(`linuxcnc_tp_set_goal_position_${result}`);
+    return this.read();
+  }
+
+  setProfile(profile, tolerance = 0) {
+    const condition = profile === 0 ? 2 : profile === 1 ? 0 : profile === 2 ? 1 : -1;
+    if (![0, 1, 2].includes(profile) || !Number.isFinite(Number(tolerance)) || Number(tolerance) < 0) throw new Error("linuxcnc_tp_profile_invalid");
+    if (this.available) {
+      const result = call(this.core, "sim_linuxcnc_tp_set_profile", "number", ["number", "number", "number"], [this.planner, condition, Number(tolerance)]);
+      if (result !== 0) throw new Error(`linuxcnc_tp_profile_${result}`);
+    }
+    this.controls.profile = profile;
+    return this.read();
+  }
+
+  setTermCondition(mode, tolerance = 0) {
+    const profile = mode === "continuous" || mode === 0 ? 0 : mode === "exact_path" || mode === 1 ? 2 : 1;
+    return this.setProfile(profile, tolerance);
+  }
+
+  setLookahead(value) { if (!Number.isSafeInteger(value) || value < 1) throw new Error("linuxcnc_tp_lookahead_invalid"); this.controls.lookahead = value; return this.read(); }
+  setDynamics(accelerationLimit, jerkLimit) { this.accelerationLimit = Number(accelerationLimit); this.controls.acceleration_limit = this.accelerationLimit; this.controls.jerk_limit = Number(jerkLimit); if (this.available) call(this.core, "sim_linuxcnc_tp_set_dynamics", "number", ["number", "number"], [this.planner, this.accelerationLimit]); return this.read(); }
+  setFeedOverride(value) { this.controls.feed_override = Number(value); if (this.available) call(this.core, "sim_linuxcnc_tp_set_feed_override", "number", ["number", "number"], [this.planner, this.controls.feed_override]); return this.read(); }
+  setPaused(value) { this.controls.paused = Boolean(value); if (this.available) call(this.core, "sim_linuxcnc_tp_set_paused", "number", ["number", "number"], [this.planner, this.controls.paused ? 1 : 0]); return this.read(); }
+
+  enqueue(segment) {
+    if (!this.available || !segment) return { status: "skipped", code: "linuxcnc_tp_unavailable" };
+    this.core.HEAPF64.set(poseArray(segment.end), this.posePointer / 8);
+    const canonMotionType = Number(segment.canon_motion_type ?? (segment.motion_type === 2 ? 3 : segment.kind === "rapid" ? 1 : 2));
+    this.activeTag = Number(segment.kinematics_mode ?? segment.tag ?? 0);
+    const segmentTag = this.activeTag;
+    const segmentId = Number(segment.source_line ?? 0);
+    if (segmentId > 0) this.segmentTags.set(segmentId, segmentTag);
+    const acceleration = Math.max(Number(segment.acceleration ?? 0), this.accelerationLimit);
+    const result = segment.motion_type === 2
+      ? (this.core.HEAPF64.set([Number(segment.center?.x ?? 0), Number(segment.center?.y ?? 0), Number(segment.center?.z ?? 0)], this.centerPointer / 8), this.core.HEAPF64.set([Number(segment.normal?.x ?? 0), Number(segment.normal?.y ?? 0), Number(segment.normal?.z ?? 0)], this.normalPointer / 8), call(this.core, "sim_linuxcnc_tp_add_circle", "number", ["number", "number", "number", "number", "number", "number", "number", "number", "number"], [this.planner, this.posePointer, this.centerPointer, this.normalPointer, Number(segment.turn ?? 1), Number(segment.velocity ?? 0), acceleration, Number(segment.source_line ?? 0), canonMotionType]))
+      : call(this.core, "sim_linuxcnc_tp_add_line", "number", ["number", "number", "number", "number", "number", "number"], [this.planner, this.posePointer, Number(segment.velocity ?? 0), acceleration, Number(segment.source_line ?? 0), canonMotionType]);
+    if (result !== 0) return { status: "error", code: `linuxcnc_tp_enqueue_${result}` };
+    if (this.lastState?.active_id && Number(this.lastState.active_id) !== segmentId) this.activeTag = Number(this.lastState.active_tag ?? this.activeTag);
+    return { status: "verified", source_line: segment.source_line ?? null };
+  }
+
+  setKinematics(kinematics) { this.kinematics = kinematics ?? null; return this.read(); }
+
+  setActiveKinematicsTag(mode) {
+    this.activeTag = Number(mode) === 0 ? 0 : Number(mode);
+    return this.read();
+  }
+
+  setExecutionState(value) {
+    const state = Number(value);
+    if (![2, 3, 4].includes(state)) throw new Error("linuxcnc_tp_execution_state_invalid");
+    this.executionState = state;
+    // The next source TP step publishes the state. Avoid a redundant C read
+    // on every servo tick merely to attach this task/TP handoff marker.
+    return { status: "verified", state: this.lastState };
+  }
+
+  queueDepth() { return Number(this.lastState?.queue_depth ?? 0); }
+
+  setQueueDepthOverride(value) {
+    this.queueDepthOverride = value === null ? null : Math.max(0, Number(value));
+    if (this.lastState && this.queueDepthOverride !== null) this.lastState.queue_depth = this.queueDepthOverride;
+    return this.read();
+  }
+
+  commandedJoints(position, activeTag) {
+    if (Number(activeTag) === 0) return [position.x, position.y, position.z, position.a ?? 0, position.c ?? 0];
+    const inverse = this.kinematics?.inverseMode?.(Number(activeTag), position) ?? this.kinematics?.inverse?.(position);
+    if (inverse?.status === "verified" && Array.isArray(inverse.joints)) return inverse.joints.slice(0, 5);
+    return this.previousJointCommanded.slice();
+  }
+
+  step() {
+    if (!this.available) return { status: "blocked", code: "linuxcnc_tp_unavailable" };
+    if (this.controls.paused) return { status: "error", code: "linuxcnc_tp_paused" };
+    const result = call(this.core, "sim_linuxcnc_tp_step", "number", ["number"], [this.planner]);
+    if (result !== 0) return { status: "error", code: `linuxcnc_tp_step_${result}` };
+    const state = this.read();
+    if (state.status === "verified") {
+      const targetJoints = this.commandedJoints(state.state.position, state.state.active_tag);
+      targetJoints.forEach((point, index) => cubicAdd(this.cubic[index], point, this.cycleTime));
+      const commanded = this.cubic.map((axis) => cubicInterpolate(axis, this.cycleTime));
+      state.state.joint_commanded = commanded;
+      state.state.joint_actual = this.previousJointCommanded.slice();
+      this.previousJointCommanded = commanded.slice();
+    }
+    if (state.status === "verified") this.history.push(structuredClone(state.state));
+    return state;
+  }
+
+  idle() {
+    if (!this.available) return this.read();
+    const result = call(this.core, "sim_linuxcnc_tp_idle", "number", ["number"], [this.planner]);
+    if (result !== 0) return { status: "error", code: `linuxcnc_tp_idle_${result}` };
+    const state = this.read();
+    if (state.status === "verified") {
+      const targetJoints = this.commandedJoints(state.state.position, state.state.active_tag);
+      targetJoints.forEach((point, index) => cubicAdd(this.cubic[index], point, this.cycleTime));
+      const commanded = this.cubic.map((axis) => cubicInterpolate(axis, this.cycleTime));
+      state.state.joint_commanded = commanded;
+      state.state.joint_actual = this.previousJointCommanded.slice();
+      this.previousJointCommanded = commanded.slice();
+    }
+    if (state.status === "verified") this.history.push(structuredClone(state.state));
+    return state;
+  }
+
+  drainTrace() { const trace = this.history; this.history = []; return trace; }
+
+  read() {
+    if (!this.available) return { status: "blocked", state: { position: toPose([]), velocity: 0, progress: 0, tick: 0, queue_depth: 0, active_id: 0, active_tag: 0, motion_type: 0, status: -1214, exec_state: this.executionState, source: "linuxcnc-source-tp" } };
+    const result = call(this.core, "sim_linuxcnc_tp_read_state", "number", ["number", "number"], [this.planner, this.statePointer]);
+    if (result !== 0) return { status: "error", code: `linuxcnc_tp_read_${result}` };
+    const doubles = this.core.HEAPF64.subarray(this.statePointer / 8, this.statePointer / 8 + 11);
+    const ints = this.core.HEAPU32.subarray(this.statePointer / 4 + 22, this.statePointer / 4 + 25);
+    const activeId = ints[2];
+    if (activeId && activeId !== this.lastActiveId && this.segmentTags.has(activeId)) this.activeTag = this.segmentTags.get(activeId);
+    this.lastActiveId = activeId;
+    const state = { position: toPose(doubles), velocity: doubles[9], acceleration: this.accelerationLimit, progress: doubles[10], tick: ints[0], queue_depth: this.queueDepthOverride === null ? ints[1] : this.queueDepthOverride, active_queue: activeId ? 1 : 0, active_id: activeId, active_tag: this.activeTag, joint_commanded: this.previousJointCommanded.slice(), joint_actual: this.previousJointCommanded.slice(), motion_type: this.core.HEAP32[this.statePointer / 4 + 25], status: this.core.HEAP32[this.statePointer / 4 + 26], exec_state: this.executionState, source: "linuxcnc-source-tp" };
+    this.lastState = state;
+    return { status: "verified", state };
+  }
+
+  reset() { if (this.available) call(this.core, "sim_linuxcnc_tp_reset", "number", ["number"], [this.planner]); this.controls.paused = false; this.history = []; this.activeTag = 0; this.segmentTags.clear(); this.lastActiveId = 0; this.queueDepthOverride = null; this.executionState = 3; this.cubic = Array.from({ length: 5 }, () => cubicState()); this.previousJointCommanded = [0, 0, 0, 0, 0]; return this.read(); }
+  abort() { if (this.available) call(this.core, "sim_linuxcnc_tp_abort", "number", ["number"], [this.planner]); this.history = []; this.activeTag = 0; this.segmentTags.clear(); this.lastActiveId = 0; this.queueDepthOverride = null; this.executionState = 3; return this.read(); }
+  exportState() {
+    const current = this.read();
+    const segments = [];
+    if (this.available) {
+      const depth = Number(call(this.core, "sim_linuxcnc_tp_queue_depth", "number", ["number"], [this.planner]));
+      const size = 240;
+      const pointer = this.core._malloc(size);
+      try {
+        for (let index = 0; index < depth; index += 1) {
+          if (call(this.core, "sim_linuxcnc_tp_queue_segment", "number", ["number", "number", "number"], [this.planner, index, pointer]) !== 0) continue;
+          const values = this.core.HEAPF64.subarray(pointer / 8, pointer / 8 + 29);
+          const ints = this.core.HEAP32.subarray(pointer / 4 + 52, pointer / 4 + 54);
+          const segmentView = new DataView(this.core.HEAPU8.buffer, pointer, size);
+          const id = this.core.HEAPU32[pointer / 4 + 54];
+          segments.push({ start: toPose(values), end: toPose(values.subarray(9)), center: { x: values[18], y: values[19], z: values[20] }, normal: { x: values[21], y: values[22], z: values[23] }, velocity: values[24], acceleration: values[25], motion_type: ints[0], turn: ints[1], id, kinematics_mode: this.segmentTags.get(id) ?? this.activeTag, term_cond: this.core.HEAP32[pointer / 4 + 55], progress: segmentView.getFloat64(224, true), target: segmentView.getFloat64(232, true) });
+        }
+      } finally { this.core._free(pointer); }
+    }
+    const unsigned = { schema: SOURCE_TP_SCHEMA, cycle_time: this.cycleTime, velocity_limit: this.velocityLimit, controls: { ...this.controls }, execution_state: this.executionState, active_tag: this.activeTag, state: current.state, segments };
+    return { ...unsigned, state_hash: fnv1a64(unsigned) };
+  }
+  restoreState(value) {
+    if (!value || value.schema !== SOURCE_TP_SCHEMA || value.cycle_time !== this.cycleTime || value.velocity_limit !== this.velocityLimit || value.state_hash !== fnv1a64(Object.fromEntries(Object.entries(value).filter(([key]) => key !== "state_hash")))) throw new Error("linuxcnc_tp_restore_schema");
+    this.reset();
+    this.executionState = Number(value.execution_state ?? 3);
+    this.setProfile(value.controls?.profile ?? 0, value.controls?.tolerance ?? 0);
+    this.setFeedOverride(value.controls?.feed_override ?? 1);
+    this.setPosition(value.state?.position ?? {});
+    for (const segment of value.segments ?? []) this.enqueue({ ...segment, kinematics_mode: segment.kinematics_mode ?? value.active_tag ?? 0 });
+    if (this.available && value.state) {
+      this.core.HEAPF64.set(poseArray(value.state.position), this.posePointer / 8);
+      const restored = call(this.core, "sim_linuxcnc_tp_restore_progress", "number", ["number", "number", "number", "number"], [this.planner, this.posePointer, Number(value.state.velocity ?? 0), Number(value.state.tick ?? 0)]);
+      if (restored !== 0) throw new Error(`linuxcnc_tp_restore_progress_${restored}`);
+    }
+    return this.read();
+  }
+  destroy() { for (const pointer of [this.planner, this.posePointer, this.centerPointer, this.normalPointer, this.statePointer]) if (pointer && typeof this.core?._free === "function") this.core._free(pointer); this.planner = this.posePointer = this.centerPointer = this.normalPointer = this.statePointer = 0; }
+}
--- a/web/worker/wasm-program-runtime.mjs
+++ b/web/worker/wasm-program-runtime.mjs
@@ -76,6 +76,7 @@ export class WasmProgramRuntime {
    this.subroutines = [];
    this.executionSource = "";
    this.executionLines = [];
+    this.executionLineMetadata = [];
    this.rapidVelocity = 35;
    if (!this.available || typeof core?._malloc !== "function") return;
    this.pointer = core._malloc(call(core, "sim_program_size", "number", [], []));
@@ -108,6 +109,11 @@ export class WasmProgramRuntime {
      this.subroutines = [];
      this.executionSource = source;
      this.executionLines = source.split(/\r?\n/);
+      this.executionLineMetadata = this.executionLines.map((_, index) => ({ path: this.path, line: index + 1 }));
+      while (this.executionLines.length && this.executionLines.at(-1) === "") {
+        this.executionLines.pop();
+        this.executionLineMetadata.pop();
+      }
      return { status: "verified", program: this.snapshot() };
    } finally { this.core._free(pointer); }
  }
@@ -133,7 +139,7 @@ export class WasmProgramRuntime {
      if (loaded.status !== "verified") return loaded;
      temporary.setRapidVelocity(this.rapidVelocity);
      for (const subroutine of this.subroutines) {
-        const added = temporary.addSubroutine(subroutine.name, subroutine.source);
+        const added = temporary.addSubroutine(subroutine.name, subroutine.source, subroutine.path);
        if (added.status !== "verified") return added;
      }
      const started = temporary.start();
@@ -159,7 +165,7 @@ export class WasmProgramRuntime {
    if (result !== 0) throw new Error(`wasm_program_set_rapid_velocity_${result}`);
    return { status: "verified", command: "sim_program_set_rapid_velocity" };
  }
-  addSubroutine(name, source) {
+  addSubroutine(name, source, path = null) {
    if (typeof source !== "string" || source.length === 0) return { status: "error", code: "program_subroutine_invalid" };
    const bytes = new TextEncoder().encode(source);
    const pointer = this.core._malloc(bytes.byteLength);
@@ -167,12 +173,19 @@ export class WasmProgramRuntime {
    try {
      const code = call(this.core, "sim_program_add_subroutine", "number", ["number", "number", "number"], [this.pointer, pointer, bytes.byteLength]);
      if (code !== 0) return { status: "error", code: `wasm_program_add_subroutine_${code}`, result: code };
-      this.subroutines.push({ name: String(name ?? "subroutine"), source });
      if (this.executionSource && !this.executionSource.endsWith("\n")) this.executionSource += "\n";
-      if (this.executionLines.length && this.executionLines.at(-1) !== "") this.executionLines.push("");
+      if (this.executionLines.length && this.executionLines.at(-1) !== "") {
+        this.executionLines.push("");
+        this.executionLineMetadata.push({ path: null, line: 0 });
+      }
      this.executionSource += source;
-      if (this.executionLines.length && this.executionLines.at(-1) === "") this.executionLines.pop();
+      if (this.executionLines.length && this.executionLines.at(-1) === "") {
+        this.executionLines.pop();
+        this.executionLineMetadata.pop();
+      }
      this.executionLines.push(...source.split(/\r?\n/));
+      this.executionLineMetadata.push(...source.split(/\r?\n/).map((_, index) => ({ path, line: index + 1 })));
+      this.subroutines.push({ name: String(name ?? "subroutine"), path, source });
      return { status: "verified", command: "sim_program_add_subroutine", name: String(name ?? "subroutine") };
    } finally { this.core._free(pointer); }
  }
@@ -268,7 +281,8 @@ export class WasmProgramRuntime {
      const programStatus = { 0: "idle", 1: "loaded", 2: "running", 3: "paused", 4: "completed", 5: "aborted", 6: "fault" }[state.status] ?? "idle";
      const motionControl = { 0: "continuous", 1: "exact_path", 2: "exact_stop" }[state.motion_control_mode] ?? "continuous";
      const executionLineText = state.current_line > 0 ? (this.executionLines[state.current_line - 1] ?? "").trim() : "";
-      return { schema: SCHEMA, source: "linuxcnc-wasm-sim_program", ...state, motion_control: { mode: motionControl, path_tolerance: Number(state.path_tolerance ?? 0), naive_cam_tolerance: Number(state.naive_cam_tolerance ?? 0) }, active_gcodes: activeGcodes(state), loaded: state.status !== 0, line: state.current_line, currentLine: state.current_line, execution_line: state.current_line, execution_line_text: executionLineText, program_status: programStatus, path: this.path, subroutines: this.subroutines.map((subroutine) => subroutine.name), state_hash: `fnv1a64:${BigInt.asUintN(64, BigInt(hash >>> 0)).toString(16).padStart(16, "0")}`, source_hash: this.source ? fnv1a64(this.source) : null };
+      const executionMeta = state.current_line > 0 ? (this.executionLineMetadata[state.current_line - 1] ?? { path: this.path, line: state.current_line }) : { path: this.path, line: 0 };
+      return { schema: SCHEMA, source: "linuxcnc-wasm-sim_program", ...state, motion_control: { mode: motionControl, path_tolerance: Number(state.path_tolerance ?? 0), naive_cam_tolerance: Number(state.naive_cam_tolerance ?? 0) }, active_gcodes: activeGcodes(state), loaded: state.status !== 0, line: state.current_line, currentLine: state.current_line, execution_line: state.current_line, execution_line_text: executionLineText, execution_source_file: executionMeta.path, execution_source_line: executionMeta.line, program_status: programStatus, path: this.path, subroutines: this.subroutines.map((subroutine) => subroutine.name), state_hash: `fnv1a64:${BigInt.asUintN(64, BigInt(hash >>> 0)).toString(16).padStart(16, "0")}`, source_hash: this.source ? fnv1a64(this.source) : null };
    } finally { this.core._free(buffer); }
  }

@@ -278,5 +292,6 @@ export class WasmProgramRuntime {
    this.pointer = this.motionPointer = this.samplePointer = this.samplePosePointer = 0;
    this.executionSource = "";
    this.executionLines = [];
+    this.executionLineMetadata = [];
  }
 }
--- a/web/worker/wasm-xyzac-kinematics.mjs
+++ b/web/worker/wasm-xyzac-kinematics.mjs
@@ -63,7 +63,7 @@ export class WasmXyzacKinematics {
  constructor(core, options = {}) {
    this.core = core;
    this.options = { x_rot_point: 0, y_offset: 20, z_offset: 10, tool_offset: 0, limits: DEFAULT_LIMITS, ...options };
-    this.available = ["sim_kinematics_init", "sim_kinematics_switch_init", "sim_kinematics_switch_register", "sim_kinematics_switch_select", "sim_kinematics_switch_forward", "sim_kinematics_switch_inverse", "sim_kinematics_switch_active", "sim_kinematics_switch_state_hash"].every((name) => typeof core?.[`_${name}`] === "function" || typeof core?.[name] === "function");
+    this.available = ["sim_kinematics_init", "sim_kinematics_switch_init", "sim_kinematics_switch_register", "sim_kinematics_switch_select", "sim_kinematics_switch_select_physical", "sim_kinematics_switch_forward", "sim_kinematics_switch_inverse", "sim_kinematics_switch_inverse_mode", "sim_kinematics_switch_active", "sim_kinematics_switch_state_hash"].every((name) => typeof core?.[`_${name}`] === "function" || typeof core?.[name] === "function");
    this.lastCommand = null;
    this.modules = new Map();
    this.pointers = [];
@@ -128,6 +128,14 @@ export class WasmXyzacKinematics {
    return this.snapshot();
  }

+  inverseMode(mode, currentPose) {
+    if (!this.available) return { status: "blocked", code: "wasm_xyzac_unavailable" };
+    this.setPose(currentPose);
+    const result = call(this.core, "sim_kinematics_switch_inverse_mode", "number", ["number", "number", "number", "number", "number", "number"], [this.switchPointer, mode, this.posePointer, this.jointPointer, 5, this.resultPointer]);
+    if (result !== 0) return resultCode("inverse_mode", result);
+    return { status: "verified", joints: [...this.core.HEAPF64.subarray(this.jointPointer / 8, this.jointPointer / 8 + 5)] };
+  }
+
  select(mode, joints = [0, 0, 0, 0, 0]) {
    if (![MODE.identity, MODE.xyzac, MODE.userk].includes(mode)) return { status: "error", code: "wasm_xyzac_invalid_mode" };
    this.setJoints(joints);
@@ -137,6 +145,16 @@ export class WasmXyzacKinematics {
    return this.snapshot();
  }

+  selectPhysical(mode, joints = [0, 0, 0, 0, 0]) {
+    if (!this.available) return { status: "blocked", code: "wasm_xyzac_unavailable" };
+    if (![MODE.identity, MODE.xyzac, MODE.userk].includes(mode)) return { status: "error", code: "wasm_xyzac_invalid_mode" };
+    this.setJoints(joints);
+    const result = call(this.core, "sim_kinematics_switch_select_physical", "number", ["number", "number", "number", "number", "number", "number"], [this.switchPointer, mode, this.jointPointer, 5, this.posePointer, this.resultPointer]);
+    if (result !== 0) return resultCode("switch_physical", result);
+    this.lastCommand = `M${mode === MODE.xyzac ? 428 : mode === MODE.identity ? 429 : 430}`;
+    return this.snapshot();
+  }
+
  restoreState(state) {
    if (!state || state.schema !== "wasm-xyzac-kinematics.v1" || ![MODE.identity, MODE.xyzac, MODE.userk].includes(state.active_type) || !Array.isArray(state.joints) || state.joints.length !== 5) throw new Error("wasm_xyzac_restore_state_invalid");
    this.initializeSwitch();
--- a/web/workspace/sim-case-loader.mjs
+++ b/web/workspace/sim-case-loader.mjs
@@ -16,7 +16,7 @@ const CASE_KINEMATICS = Object.freeze({
  "linuxcnc/configs/sim/axis/corexy/corexy_by_hal.ini": Object.freeze({ type: "corexy", path_mode: "hal" }),
  "linuxcnc/configs/sim/axis/ldelta.ini": Object.freeze({ type: "lineardelta", path_mode: "kins" }),
  "linuxcnc/configs/sim/axis/rdelta.ini": Object.freeze({ type: "rotarydelta", path_mode: "kins" }),
-  "linuxcnc/configs/sim/axis/vismach/5axis/table-rotary-tilting/xyzac-trt.ini": Object.freeze({ type: "xyzac-trt", path_mode: "wasm", coordinates: "XYZAC", joint_count: 5, max_linear_velocity: 35, switchkins: { 0: "identity", 1: "xyzac", 2: "userk" }, offsets: { x_rot_point: 0, y_offset: 20, z_offset: 10, tool_offset: 0 } }),
+  "linuxcnc/configs/sim/axis/vismach/5axis/table-rotary-tilting/xyzac-trt.ini": Object.freeze({ type: "xyzac-trt", path_mode: "wasm", coordinates: "XYZAC", joint_count: 5, max_linear_velocity: 35, axis_linear_velocity_limit: 20, max_acceleration: 300, max_jerk: 1000000000, servo_cycle_time: 0.001, task_cycle_time: 0.01, cycle_time: 0.001, switchkins: { 0: "identity", 1: "xyzac", 2: "userk" }, offsets: { x_rot_point: 0, y_offset: 20, z_offset: 10, tool_offset: 0 } }),
 });
 const RUNTIME_FIXTURES = Object.freeze({
  "linuxcnc/configs/sim/axis/minimal_xyz.ini": Object.freeze({