Backlight policy for night riding

robert commented

2026-08-31 17:14:53 +02:00

(Migrated from git.butzei.de)

Goal

Readable after dark without destroying the battery.

Acceptance criteria

Backlight held on while riding, as an explicit opt-in mode
Ambient-aware or schedule-based automatic activation
Brief backlight on turn prompts even when the always-on mode is off
Battery cost measured and documented
Setting persists across rides

Files

watchapp/src/c/main.c

## Goal Readable after dark without destroying the battery. ## Acceptance criteria - [ ] Backlight held on while riding, as an explicit opt-in mode - [ ] Ambient-aware or schedule-based automatic activation - [ ] Brief backlight on turn prompts even when the always-on mode is off - [ ] Battery cost measured and documented - [ ] Setting persists across rides ## Files - `watchapp/src/c/main.c`

robert added a new dependency

2026-09-03 19:01:23 +02:00

#8 Watchapp skeleton: window stack, view switching, button handling

robert referenced this issue

2026-09-04 14:37:33 +02:00

Settings: units, wheel circumference, HR alerts, auto-pause, vibration #44

robert referenced this issue from a commit

2026-09-05 11:10:49 +02:00

Add backlight policy for night riding (issue #45)

robert referenced this issue

2026-09-05 11:11:16 +02:00

Backlight policy for night riding (#45) #106

robert referenced this issue from a commit

2026-09-05 11:12:29 +02:00

Merge pull request 'Backlight policy for night riding (#45)' (#106) from area/backlight-policy into main

robert commented

2026-09-05 11:13:06 +02:00

Owner

Closed by PR #106 (merged): backlight.c/.h (new module, matches the one-concern-per-file pattern), schedule-based activation (19:00-06:00 default) since the installed SDK has no live ambient-light-sensor API for apps -- checked against both emery/gabbro headers directly, not assumed. Always-on opt-in mode, turn-prompt flash function built and host-tested (backlight_flash_for_turn_prompt(), no caller yet since no turn-cue rendering exists until #33-#37 land -- honestly stated, not hidden). Persisted via a new PERSIST_KEY_BACKLIGHT_MODE in page.h's registry.

Verified for real: pebble build clean on all three platforms, 119 host assertions (27 new), and a real emulator run confirmed the exact light_enable() call sequence via pebble logs (true on RUNNING, false on STOPPED, none across pause/resume, zero calls with the shipped default off). Battery cost: heap footprint measured (13020->13252 bytes); real multi-hour drain against NFR-B1's budget still needs Robert's physical watch, honestly flagged.

Also fixed a real factual error: DESIGN.md section 7.4 claimed emery/gabbro have "no backlight" -- wrong, both have a real Light API per the installed SDK headers. Corrected with an explicit checked-fact note per D48's bar, not silently rewritten.

Closed by PR #106 (merged): backlight.c/.h (new module, matches the one-concern-per-file pattern), schedule-based activation (19:00-06:00 default) since the installed SDK has no live ambient-light-sensor API for apps -- checked against both emery/gabbro headers directly, not assumed. Always-on opt-in mode, turn-prompt flash function built and host-tested (backlight_flash_for_turn_prompt(), no caller yet since no turn-cue rendering exists until #33-#37 land -- honestly stated, not hidden). Persisted via a new PERSIST_KEY_BACKLIGHT_MODE in page.h's registry. Verified for real: pebble build clean on all three platforms, 119 host assertions (27 new), and a real emulator run confirmed the exact light_enable() call sequence via pebble logs (true on RUNNING, false on STOPPED, none across pause/resume, zero calls with the shipped default off). Battery cost: heap footprint measured (13020->13252 bytes); real multi-hour drain against NFR-B1's budget still needs Robert's physical watch, honestly flagged. Also fixed a real factual error: DESIGN.md section 7.4 claimed emery/gabbro have "no backlight" -- wrong, both have a real Light API per the installed SDK headers. Corrected with an explicit checked-fact note per D48's bar, not silently rewritten.

robert closed this issue

2026-09-05 11:13:15 +02:00

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Backlight policy for night riding #45

Goal

Acceptance criteria

Files