GPS: poll up to 5s for cold-start detection instead of a single 1s check#2838
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GPS: poll up to 5s for cold-start detection instead of a single 1s check#2838benskigomez wants to merge 1 commit into
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PR targets main instead of dev, approve when fixed. 👍🏼
initBasicGPS() waited a fixed 1 second and then decided the GPS was present only if NMEA data had already arrived. Cold-start GPS modules often need 2-5 seconds before they emit their first sentence, so on a cold boot detection frequently failed. A failed detection sets gps_detected = false, which hides all GPS CLI settings and disables GPS time sync until the next reboot - so the GPS appears permanently dead even though the hardware is fine. Poll for up to ~5 seconds (in 250ms steps) and return as soon as any data appears. Fast modules are detected almost immediately and add no boot delay; slow cold-start modules now get enough time. The ENV_SKIP_GPS_DETECT bypass is unchanged. Fixes meshcore-dev#2258.
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Problem
EnvironmentSensorManager::initBasicGPS()waits a fixed 1 second, then decides the GPS is present only if NMEA data has already arrived. Cold-start GPS modules often need 2–5 seconds before emitting their first sentence, so on a cold boot detection frequently fails.A failed detection sets
gps_detected = false, which hides all GPS CLI settings and disables GPS time sync until the next reboot — so the GPS appears permanently dead even though the hardware is fine. This affects the ~20 GPS-equipped variants that don't set theENV_SKIP_GPS_DETECT/PERSISTANT_GPSbypass flags.Fix
Poll for up to ~5 seconds (in 250 ms steps) and return as soon as any data appears. Fast modules are detected almost immediately and add no boot delay; slow cold-start modules now get enough time. The
ENV_SKIP_GPS_DETECTbypass is unchanged.Trade-off
Boards that have
ENV_INCLUDE_GPSbut no physical GPS will now wait the full ~5 s at boot (vs. 1 s before), since detection never succeeds. This seemed the right call given the alternative is GPS silently not working, but happy to shorten the cap if preferred.Testing
Builds clean (verified on a ThinkNode M6 companion build). The change is a drop-in replacement for the single check.
Fixes #2258.