run 10

docs/discovery-notes.md

@@ -3086,3 +3086,57 @@ python scripts/serial_button_response_test.py --port COM5 --duration 15 --prompt
 ```
 
 For each run, power-cycle first and use the same roughly 2 second CALL hold.
+
+### 2026-05-13 CALL Inter-Frame Gap Result
+
+Captures:
+
+- `captures/rcp-buttons-call-frame-gap-20ms.txt`
+- `captures/rcp-buttons-call-frame-gap-50ms.txt`
+- `captures/rcp-buttons-call-frame-gap-80ms.txt`
+- `captures/rcp-buttons-call-delay-80ms-frame-gap-50ms.txt`
+
+Observed result:
+
+| Initial delay | Gap between host CALL echoes | Result |
+| --- | --- | --- |
+| 50 ms | 20 ms | `07 80 45 20 D0 68` |
+| 50 ms | 50 ms | `07 80 45 20 D0 68` |
+| 50 ms | 80 ms | `07 80 45 20 D0 68` |
+| 80 ms | 50 ms | `07 80 45 20 D0 68` |
+
+Interpretation:
+
+- `07 80 45 20 D0 68` is now reproducible.
+- The key change was adding a gap between the host's CALL-high echo and
+  CALL-low echo. Earlier tests sent the two response frames back-to-back.
+- The exact gap is not especially narrow; 20 ms, 50 ms, and 80 ms all worked in
+  this run set.
+- The RCP likely needs to process the high echo as one event before receiving
+  the low echo. Sending high and low in one tight burst can land outside that
+  event path.
+- The `0x45` response is still not known to activate the panel, but it is a
+  real, reproducible event-response path.
+
+Next step: answer the reproducible `0x45` response in the same run.
+
+Test F1: host-shaped generic `0x45` ACK.
+
+```powershell
+python scripts/serial_button_response_test.py --port COM5 --duration 15 --prompt --respond-to-call --respond-once --response-delay 0.05 --response-frame-interval 0.05 --response-frame "00 00 15 80 00 CF" --response-frame "00 00 15 00 00 4F" --watch-frame "07 80 45 20 D0 68" --followup-on-watch-frame --followup-frame "00 00 45 00 80 9F" --log captures/rcp-buttons-call-45-followup-generic-ack.txt
+```
+
+Test F2: host-shaped echo of the RCP `0x45` payload.
+
+```powershell
+python scripts/serial_button_response_test.py --port COM5 --duration 15 --prompt --respond-to-call --respond-once --response-delay 0.05 --response-frame-interval 0.05 --response-frame "00 00 15 80 00 CF" --response-frame "00 00 15 00 00 4F" --watch-frame "07 80 45 20 D0 68" --followup-on-watch-frame --followup-frame "00 00 45 20 D0 EF" --log captures/rcp-buttons-call-45-followup-payload-echo.txt
+```
+
+Test F3: exact echo of the RCP `0x45` response frame.
+
+```powershell
+python scripts/serial_button_response_test.py --port COM5 --duration 15 --prompt --respond-to-call --respond-once --response-delay 0.05 --response-frame-interval 0.05 --response-frame "00 00 15 80 00 CF" --response-frame "00 00 15 00 00 4F" --watch-frame "07 80 45 20 D0 68" --followup-on-watch-frame --followup-frame "07 80 45 20 D0 68" --log captures/rcp-buttons-call-45-followup-exact-echo.txt
+```
+
+For each follow-up test, note whether the LCD changes, whether more serial data
+appears after the follow-up, and whether the panel returns to heartbeat only.