ESP32-PaxCounter/src/gps.cpp
2018-09-21 12:25:52 +02:00

72 lines
1.9 KiB
C++

#ifdef HAS_GPS
#include "globals.h"
// Local logging tag
static const char TAG[] = "main";
TinyGPSPlus gps;
gpsStatus_t gps_status;
// read GPS data and cast to global struct
void gps_read() {
gps_status.latitude = (int32_t)(gps.location.lat() * 1e6);
gps_status.longitude = (int32_t)(gps.location.lng() * 1e6);
gps_status.satellites = (uint8_t)gps.satellites.value();
gps_status.hdop = (uint16_t)gps.hdop.value();
gps_status.altitude = (int16_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);
GPS_Serial.begin(GPS_SERIAL);
#elif defined GPS_QUECTEL_L76
uint8_t ret;
Wire.begin(GPS_QUECTEL_L76, 400000); // I2C connect to GPS device with 400 KHz
Wire.beginTransmission(GPS_ADDR);
Wire.write(0x00); // dummy write
ret = Wire.endTransmission(); // check if chip is seen on i2c bus
if (ret) {
ESP_LOGE(TAG,
"Quectel L76 GPS chip not found on i2c bus, bus error %d. "
"Stopping GPS-Task.",
ret);
vTaskDelete(GpsTask);
} else {
ESP_LOGI(TAG, "Quectel L76 GPS chip found.");
}
#endif
while (1) {
if (cfg.gpsmode) {
#if defined GPS_SERIAL
// feed GPS decoder with serial NMEA data from GPS device
while (GPS_Serial.available()) {
gps.encode(GPS_Serial.read());
}
#elif defined GPS_QUECTEL_L76
Wire.requestFrom(GPS_ADDR, 32); // caution: this is a blocking call
while (Wire.available()) {
gps.encode(Wire.read());
vTaskDelay(2 / portTICK_PERIOD_MS); // 2ms delay according L76 datasheet
}
#endif
} // if (cfg.gpsmode)
vTaskDelay(2 / portTICK_PERIOD_MS); // yield to CPU
} // end of infinite loop
} // gps_loop()
#endif // HAS_GPS