ESP32-PaxCounter/src/gpsread.cpp

#ifdef HAS_GPS

#include "globals.h"

// Local logging tag
static const char TAG[] = "main";

// read GPS data and cast to global struct
void gps_read() {
  gps_status.latitude = (uint32_t)(gps.location.lat() * 1000000);
  gps_status.longitude = (uint32_t)(gps.location.lng() * 1000000);
  gps_status.satellites = (uint8_t)gps.satellites.value();
  gps_status.hdop = (uint16_t)gps.hdop.value();
  gps_status.altitude = (uint16_t)gps.altitude.meters();
}

// GPS serial feed FreeRTos Task
void gps_loop(void *pvParameters) {

  configASSERT(((uint32_t)pvParameters) == 1); // FreeRTOS check

// initialize and, if needed, configure, GPS
#if defined GPS_SERIAL
  HardwareSerial GPS_Serial(1);
#elif defined GPS_I2C
                                               // to be done
#endif

  while (1) {

    if (cfg.gpsmode) {
#if defined GPS_SERIAL

      // serial connect to GPS device
      GPS_Serial.begin(GPS_SERIAL);

      while (cfg.gpsmode) {
        // feed GPS decoder with serial NMEA data from GPS device
        while (GPS_Serial.available()) {
          gps.encode(GPS_Serial.read());
        }
        vTaskDelay(1 / portTICK_PERIOD_MS); // reset watchdog
      }
      // after GPS function was disabled, close connect to GPS device
      GPS_Serial.end();

#elif defined GPS_I2C

      // I2C connect to GPS device with 100 kHz
      Wire.begin(GPS_I2C_PINS, 100000);
      Wire.beginTransmission(GPS_I2C_ADDRESS_WRITE);
      Wire.write(0x00);

      i2c_ret == Wire.beginTransmission(GPS_I2C_ADDRESS_READ);
      if (i2c_ret == 0) { // check if device seen on i2c bus
        while (cfg.gpsmode) {
          // feed GPS decoder with serial NMEA data from GPS device
          while (Wire.available()) {
            Wire.requestFrom(GPS_I2C_ADDRESS_READ, 255);
            gps.encode(Wire.read());
            vTaskDelay(1 / portTICK_PERIOD_MS); // reset watchdog
          }
        }
        // after GPS function was disabled, close connect to GPS device

        Wire.endTransmission();
        Wire.setClock(400000); // Set back to 400KHz to speed up OLED
      }

#endif
    }

    vTaskDelay(1 / portTICK_PERIOD_MS); // reset watchdog

  } // end of infinite loop

} // gps_loop()

#endif // HAS_GPS