thinknode_m1: stop GPS code from driving the LoRa radio power pin#2865
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benskigomez wants to merge 1 commit into
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thinknode_m1: stop GPS code from driving the LoRa radio power pin#2865benskigomez wants to merge 1 commit into
benskigomez wants to merge 1 commit into
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On the M1, pin 37 is the LoRa radio power enable (SX126X_POWER_EN, driven HIGH by ThinkNodeM1Board), but variant.h also defined PIN_GPS_RESET (37) -- the same pin. Because the M1 builds its location provider with default args, MicroNMEALocationProvider drives that pin as if it were the GPS reset: begin() drives it HIGH and stop() drives it LOW. So turning GPS off (e.g. via the GPS switch) cuts power to the LoRa radio. The M1 GPS has no MCU-controlled reset line. Remove the bogus PIN_GPS_RESET and set GPS_RESET (-1) so the provider never touches pin 37; the radio keeps it powered. GPS is unaffected (the L76K streams NMEA without a reset pulse; verified on hardware -- 3D fix in ~80s).
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Problem
On the ThinkNode M1, pin 37 is the LoRa radio power enable (
SX126X_POWER_EN=37, driven HIGH inThinkNodeM1Board.cpp). Butvariants/thinknode_m1/variant.halso definedPIN_GPS_RESET (37)— the same pin.The M1 builds its location provider with default constructor args:
MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1, &rtc_clock); // -> pin_reset = GPS_RESET = PIN_GPS_RESET = 37So
MicroNMEALocationProviderdrives pin 37 thinking it's the GPS reset:begin()drives it HIGH andstop()drives it LOW. The result is that turning GPS off (e.g. via the GPS switch) drives pin 37 low and cuts power to the LoRa radio. The constructor also drives it low at static-init time before the board powers the radio.Fix
The M1 GPS has no MCU-controlled reset line. Remove the incorrect
PIN_GPS_RESET (37)define and setGPS_RESET (-1)so the location provider never touches pin 37. The radio driver continues to own that pin and keeps it powered.GPS is unaffected — the L76K streams NMEA without any reset pulse. Verified on hardware: the M1 GPS acquires normally and gets a 3D fix in ~80 s.
Note
This is the M1 analogue of the M6 REINIT-pin issue (#2863): in both cases the location provider was driving a pin that must not be driven. Different pin, different consequence (M6 silenced the GPS; M1 cuts the radio), same root pattern.