dashboard: add passive CAN capture markers

2026-07-26 15:26:42 -06:00
parent ed9611310e
commit 8c2375d402
6 changed files with 227 additions and 56 deletions
@@ -76,13 +76,37 @@ The dashboard uses field-filtered `/api/v1/status` calls:

 This keeps the endpoint model simple while reducing payload size, JSON parsing, and UI churn.

-## OBD-II / CAN Diagnostics
+## Passive CAN Logger

-The hidden diagnostics overlay distinguishes raw CAN traffic from parsed
-OBD-II coolant responses. It reports request successes and failures, total
-raw frames received, the last frame identifier and DLC, TWAI queue depth,
-controller error counters, missed or overrun frames, arbitration losses,
-and bus errors.
+The dashboard runs its 500 kbps TWAI controller in listen-only mode and never
+transmits onto the vehicle bus. At 115200 baud it prints changed frames as:

-Raw RX activity confirms that the display is receiving CAN frames even when
-the vehicle does not return a matching Mode 01 PID 05 coolant response.
+    CAN,ms,id,format,dlc,b0,b1,b2,b3,b4,b5,b6,b7
+
+During a cold-start warm-up, enter the scan-tool coolant reading periodically:
+
+    TEMP,68
+    TEMP,95
+    TEMP,140
+
+Generic timestamped markers can be added with `MARK,<label>`. For a stationary
+4WD capture, start in 2H and enter each marker only after the corresponding
+dashboard indicator has settled:
+
+    MARK,2H
+    MARK,4H
+    MARK,4LO
+    MARK,4H
+    MARK,2H
+
+Wait 10-15 seconds between mode changes. Follow the vehicle owner's manual for
+the conditions required to select 4LO, keep the vehicle stationary where
+required, and save the complete serial output. The repeated return transitions
+help distinguish an actual mode signal from unrelated counters and timers.
+
+Save the serial output, then rank CAN ID/byte candidates with:
+
+    python tools/analyze_can_coolant.py can-warmup.log
+
+Verify strong candidates over multiple warm-up captures before using one for
+the dashboard gauge.