Roadmap: off-board session retention goal; CAN bring-up, OBD and capture status

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

docs/ROADMAP.md

@@ -1,7 +1,7 @@
 ---
 type: plan
 status: active
-updated: 2026-10-12
+updated: 2026-10-13
 ---
 # Roadmap
 
@@ -15,7 +15,8 @@ Getting the Jetson to see the hardware at all.
 - [x] PCAN-USB working as SocketCAN (out-of-tree `pcan.ko`, netdev build)
 - [x] Stable CAN names by udev: `can_pcan`, `can_onboard` — `canN` order raced at boot
 - [x] Z27AG OBD-port CAN measured: 500 kbps, not gatewayed, 27 periodic IDs at
-      ~890 frames/s; `can_pcan` comes up at 500k listen-only on boot and hot-plug
+      ~890 frames/s; `can_pcan` comes up at 500k on hot-plug (verified 2026-10-13;
+      boot not yet seen), acknowledging rather than listen-only
 - [x] SIM7600G-H-M.2 specified and documented
 - [x] SIM7600 LTE data path: QMI (self-built `qmi_wwan`), povo, metered, ranked
       below Ethernet/WiFi; failover tested, Tailscale stays reachable over LTE
@@ -44,6 +45,10 @@ Get real Z27AG traffic onto disk before designing anything around it.
 - [x] `recorder` — raw CAN + GNSS sessions on the car unit (`yukart-recorder.service`):
       starts on traffic or `ctl start`, ends after 15 s idle, marks via `ctl mark` or
       the app; fsync'd every second, bounded at 50 GB, ~20 MB per hour of driving
+- [ ] Off-board retention: sessions roll off the car unit once copied to dedicated
+      storage (halogen over tailnet/WiFi, or object storage such as S3), instead of
+      living on board until the cap. Not urgent: first checklist session was 6.2 MB
+      for 16 min, 423 GB free (2026-10-13)
 - [ ] `can-bridge` — listen-only, timestamped frames onto the bus
 - [ ] Capture drive sessions across varied conditions (idle, cold start, moving,
       lights/indicators/windows actuated) with a written log of what was done when
@@ -61,11 +66,14 @@ mark …`, or the app's Mark button), on the same clock as the frames.
 - [ ] `decoder` — raw frames to named signals
 - [x] `obd-poller` — active OBD-II PIDs, single writer, 2026-10-12: mode 01, the
       nine `obd2` signals (~10 Hz fast, 1 Hz slow), only while the bus is alive;
-      `can_pcan` out of listen-only. Recorded beside the frames (`vehicle.ndjson`)
+      `can_pcan` out of listen-only. Recorded beside the frames (`vehicle.ndjson`).
+      **Disabled 2026-10-13:** the Z27AG doesn't answer OBD-II on CAN (likely
+      K-line, pin 7); kept for later active-send use
 - [ ] OBD-II beyond mode 01: DTC scan (modes 03/07/0A) and MUT-III `21 xx`
       requests, both needing multi-frame (ISO-TP) replies
 - [ ] First decoding captures in the car, per contracts
-      `docs/impl/plans/Z27AG-CAPTURES.md`
+      `docs/impl/plans/Z27AG-CAPTURES.md` — first checklist session 2026-10-13
+      (117 marks, yukart-data `can-captures/`); jack-stands section still to do
 - [ ] `gnss` — position/speed, useful as ground truth for validating decoded speed
 
 OBD-II gives standardised signals quickly and is worth doing early; it also