ESP32-PaxCounter/src/gpsread.cpp
Klaus K Wilting 75fb08e72c v1.6.85
2018-11-25 16:35:36 +01:00

86 lines
2.2 KiB
C++

#ifdef HAS_GPS
#include "globals.h"
// Local logging tag
static const char TAG[] = "main";
TinyGPSPlus gps;
gpsStatus_t gps_status;
TaskHandle_t GpsTask;
#ifdef GPS_SERIAL
HardwareSerial GPS_Serial(1);
#endif
// initialize and configure GPS
int gps_init(void) {
int ret = 1;
#if defined GPS_SERIAL
GPS_Serial.begin(GPS_SERIAL);
ESP_LOGI(TAG, "Using serial GPS");
#elif defined GPS_I2C
Wire.begin(GPS_I2C, 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);
ret = 0;
} else {
ESP_LOGI(TAG, "Quectel L76 GPS chip found");
}
#endif
return ret;
} // gps_init()
// 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();
// show NMEA data in debug mode, useful for debugging GPS
ESP_LOGD(TAG, "GPS NMEA data: passed %d / failed: %d / with fix: %d",
gps.passedChecksum(), gps.failedChecksum(), gps.sentencesWithFix());
}
// GPS serial feed FreeRTos Task
void gps_loop(void *pvParameters) {
configASSERT(((uint32_t)pvParameters) == 1); // FreeRTOS check
while (1) {
if (cfg.payloadmask && GPS_DATA) {
#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_I2C
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
vTaskDelay(2 / portTICK_PERIOD_MS); // yield to CPU
} // end of infinite loop
vTaskDelete(GpsTask); // shoud never be reached
} // gps_loop()
#endif // HAS_GPS