T-Echo Card: switch GPS LNA with GPS power, enable L76K config

variants/lilygo_techo_card/TechoCardBoard.cpp

@@ -20,6 +20,7 @@ Adafruit_NeoPixel *Led[] =
 
 void TechoCardBoard::begin() {
     NRF52BoardDCDC::begin();
+    gps_rf_power.begin();  // LNA stays off until the GPS is started
     Wire.begin();
 
     for (uint8_t i = 0; i < sizeof(Led) / sizeof(Led[0]); i++)

variants/lilygo_techo_card/TechoCardBoard.h

@@ -3,6 +3,7 @@
 #include <MeshCore.h>
 #include <Arduino.h>
 #include <helpers/NRF52Board.h>
+#include <helpers/RefCountedDigitalPin.h>
 #include <Adafruit_NeoPixel.h>
 
 // built-ins
@@ -17,7 +18,9 @@
 class TechoCardBoard : public NRF52BoardDCDC {
   bool _torchStatus = false;
 public:
-  TechoCardBoard() : NRF52Board("TECHO_OTA") {}
+  RefCountedDigitalPin gps_rf_power;  // GPS antenna LNA, claimed while the GPS is running
+
+  TechoCardBoard() : NRF52Board("TECHO_OTA"), gps_rf_power(PIN_GPS_RF_EN, HIGH) {}
   void begin();
   uint16_t getBattMilliVolts() override;
   void onBeforeTransmit(void) override;

variants/lilygo_techo_card/target.cpp

@@ -13,7 +13,7 @@ VolatileRTCClock fallback_clock;
 AutoDiscoverRTCClock rtc_clock(fallback_clock);
 
 #ifdef ENV_INCLUDE_GPS
-MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1, &rtc_clock);
+MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1, &rtc_clock, GPS_RESET, GPS_EN, &board.gps_rf_power);
 EnvironmentSensorManager sensors = EnvironmentSensorManager(nmea);
 #else
 EnvironmentSensorManager sensors = EnvironmentSensorManager();

variants/lilygo_techo_card/variant.cpp

@@ -34,9 +34,9 @@ void initVariant() {
   pinMode(SPEAKER_EN_2, OUTPUT);
   digitalWrite(SPEAKER_EN_2, LOW);
 
-  // gps
-  pinMode(PIN_GPS_STANDBY, OUTPUT);
-  digitalWrite(PIN_GPS_STANDBY, HIGH);
+  // gps - PIN_GPS_RF_EN (LNA) is switched by TechoCardBoard::gps_rf_power
+  pinMode(PIN_GPS_RF_EN, OUTPUT);
+  digitalWrite(PIN_GPS_RF_EN, LOW);
   pinMode(PIN_GPS_EN, OUTPUT);
   digitalWrite(PIN_GPS_EN, HIGH);
   pinMode(PIN_GPS_RESET, OUTPUT);

variants/lilygo_techo_card/variant.h

@@ -113,15 +113,18 @@
 ////////////////////////////////////////////////////////////////////////////////
 // GPS
 
-// NOTE: these pins are defined differently to how lilygo does them but they
-// seem to work properly for how EnvironmentSensorManager operates.
+// NOTE: these pins are named differently to how lilygo does them but they
+// work properly for how EnvironmentSensorManager operates. LilyGo's own
+// examples switch the GPS on/off by driving GPS_WAKE_UP and GPS_RF_EN together.
 // TODO: MAYBE? migrate to board based sensor manager / add GPS_WAKE_UP to ESM
 
+#define GPS_L76K                     // Quectel L76K: applies GPS+BDS+GLONASS config on start
+
 #define PIN_GPS_RX              (21) // GPS_UART_RX in lilygo pin defs
 #define PIN_GPS_TX              (19) // GPS_UART_TX in lilygo pin defs
 #define PIN_GPS_EN              (25) // GPS_WAKE_UP in lilygo pin defs
 #define PIN_GPS_RESET           (47) // GPS_EN      in lilygo pin defs
-#define PIN_GPS_STANDBY         (29) // GPS_RF_EN   in lilygo pin defs
+#define PIN_GPS_RF_EN           (29) // GPS_RF_EN   in lilygo pin defs (antenna LNA), follows GPS on/off
 #define PIN_GPS_PPS             (23) // GPS_1PPS    in lilygo pin defs
 
 // buzzer - enabled in platformio.ini so it can be easily turned off if not wanted.