@@ -0,0 +1,90 @@
+#!/usr/bin/env python3
+"""Print the PiPER's protection settings and driver status, without moving or changing anything.
+
+Runs on the arm Pi, in the venv that has piper_sdk (~/piper-venv):
+
+    ~/piper-venv/bin/python piper_status.py
+
+Shows what decides how the arm reacts when it is blocked: each joint's collision protection
+level (0 means no collision detection), each driver's fault flags (under-voltage,
+over-current, motor and driver over-temperature, collision, stall), the temperatures, and the
+arm status code.
+
+The only frames it sends are queries: ConnectPort's limit and firmware queries, and 0x477 with
+Byte 0 = 0x02 (query collision protection level). It never enables the motors, commands
+motion, or writes a setting. can0 must already be up at 1 Mbit/s; this script never touches
+the interface.
+"""
+import argparse
+import os
+import sys
+import time
+
+FLAGS = ["voltage_too_low", "motor_overheating", "driver_overcurrent", "driver_overheating",
+         "collision_status", "driver_error_status", "stall_status"]
+
+
+def wait_for(pred, timeout_s=3.0):
+    t0 = time.time()
+    while time.time() - t0 < timeout_s:
+        if pred():
+            return True
+        time.sleep(0.05)
+    return False
+
+
+def main():
+    ap = argparse.ArgumentParser(description=__doc__,
+                                 formatter_class=argparse.RawDescriptionHelpFormatter)
+    ap.add_argument("--can", default="can0")
+    args = ap.parse_args()
+
+    state = open(f"/sys/class/net/{args.can}/operstate").read().strip() \
+        if os.path.exists(f"/sys/class/net/{args.can}") else "missing"
+    if state not in ("up", "unknown"):
+        sys.exit(f"{args.can} is {state}; bring it up at 1 Mbit/s first")
+
+    from piper_sdk import C_PiperInterface_V2
+
+    piper = C_PiperInterface_V2(args.can)
+    piper.ConnectPort()
+    if not wait_for(lambda: piper.GetArmLowSpdInfoMsgs().Hz > 0):
+        sys.exit("no driver feedback on the bus: is the arm powered and wired to the adapter?")
+
+    # Query only: param_setting, 0x48X feedback and end load are left at "no change".
+    def crash_levels():
+        piper.ArmParamEnquiryAndConfig(param_enquiry=0x02)
+        time.sleep(0.05)
+        return piper.GetCrashProtectionLevelFeedback().time_stamp > 0
+    have_crash = wait_for(crash_levels)
+    time.sleep(0.5)  # let a few more feedback frames arrive
+
+    print("firmware:", piper.GetPiperFirmwareVersion())
+    st = piper.GetArmStatus().arm_status
+    print(f"ctrl mode: {st.ctrl_mode}  arm status: {st.arm_status}  motion: {st.motion_status}"
+          f"  err code: {st.err_code}")
+    errs = [k for k, v in vars(st.err_status).items() if v]
+    print("err flags:", ", ".join(errs) or "none")
+
+    js = piper.GetArmJointMsgs().joint_state
+    q = [js.joint_1, js.joint_2, js.joint_3, js.joint_4, js.joint_5, js.joint_6]
+    print("joints (deg):", "[" + ", ".join(f"{v / 1000:7.2f}" for v in q) + "]")
+
+    if have_crash:
+        c = piper.GetCrashProtectionLevelFeedback().crash_protection_level_feedback
+        levels = [getattr(c, f"joint_{i}_protection_level") for i in range(1, 7)]
+        print("collision protection level J1-J6:", levels, "(0 = no collision detection)")
+    else:
+        print("collision protection level: no reply to the 0x477 query")
+
+    low = piper.GetArmLowSpdInfoMsgs()
+    print("joint  volts  driver_C  motor_C  enabled  faults")
+    for i in range(1, 7):
+        m = getattr(low, f"motor_{i}")
+        faults = [f for f in FLAGS if getattr(m.foc_status, f)]
+        print(f"J{i}  {m.vol / 10:9.1f}  {m.foc_temp:8d}  {m.motor_temp:7d}"
+              f"  {str(m.foc_status.driver_enable_status):>7}  {', '.join(faults) or 'none'}")
+
+
+if __name__ == "__main__":
+    main()