ESP32_GPS.ino

/**
 * Rob 5/16/2019
 * Github: Rob4226
 * 
 * Basic code using U-blox based GPS module via UART 
 * using HardwareSerial and NeoGPS Arudino library to 
 * parse various NMEA sentences with ESP32 or other boards.
 * 
 * */

#include <Arduino.h>
#include <NMEAGPS.h>

//-------------------------------------------------------------------------
// Check that the config files are set up properly
#if !defined(NMEAGPS_PARSE_RMC) & \
    !defined(NMEAGPS_PARSE_GGA) & \
    !defined(NMEAGPS_PARSE_GLL)
#error You must uncomment at least one of NMEAGPS_PARSE_RMC, NMEAGPS_PARSE_GGA or NMEAGPS_PARSE_GLL in NMEAGPS_cfg.h!
#endif

#if !defined(GPS_FIX_LOCATION)
#error You must uncomment GPS_FIX_LOCATION in GPSfix_cfg.h!
#endif

#define gpsPort Serial2 //ESP32 pins 16RX, 17TX  UART02

#define GPS_PORT_NAME "Serial2"
#define DEBUG_PORT Serial
#define BAUD_GPS 9600
#define BAUD_USB_SERIAL 115200
#define fixLEDPin 2
int incomingByte = 0;

using namespace NeoGPS;
NMEAGPS gps;

int batt;
int last_batt = 9000;
float lat=0.0, lng = 0.0;
int alt=0;

static void doSomeWork( const gps_fix & fix );
static void doSomeWork( const gps_fix & fix )
{
  if (fix.valid.location) {
    lat = fix.latitude();
    lng = fix.longitude();
    alt = fix.altitude();
    Serial.println(lat,6);
    Serial.println(lng,6);

  } 
} // doSomeWork

void setup()
{
  Serial.begin(BAUD_USB_SERIAL);
  pinMode(fixLEDPin, OUTPUT);
  gpsPort.begin(BAUD_GPS);

  //pinMode(34, INPUT); //vlažnost zemlje
  adcAttachPin(34);
  analogReadResolution(12);
  analogSetAttenuation(ADC_11db);

  // Wait for USB Serial
  while (!Serial)
  {
    yield();
  }

  // By default, "16E TTL" and other U-blox GPS modules output RMC, VTG, CGA, GSA, GSV, GLL messages once a second (these are standard NMEA messages)
  // Configure the GPS to only output what is needed, like just RMC as is shown below by disabling all other default sentences.
  
  //gpsPort.println(F("$PUBX,40,RMC,0,0,0,0*47")); //RMC ON (Comented out to leave RMC on...uncomment this line to disable RMC)
  //delay(100);
  gpsPort.println(F("$PUBX,40,VTG,0,0,0,0*5E")); //VTG OFF
  delay(100);
  gpsPort.println(F("$PUBX,40,GGA,0,0,0,0*5A")); //GGA OFF
  delay(100);
  gpsPort.println(F("$PUBX,40,GSA,0,0,0,0*4E")); //GSA OFF
  delay(100);
  gpsPort.println(F("$PUBX,40,GSV,0,0,0,0*59")); //GSV OFF
  delay(100);
  gpsPort.println(F("$PUBX,40,GLL,0,0,0,0*5C")); //GLL OFF
  delay(100);
}

void loop()
{
  while (gpsPort.available()) // basically true every second if 1Hz from GPS, only true when the GPS returns a sentence
  {
    gps_fix fix = gps.read(); // save the latest
    incomingByte = gpsPort.read();  // Clear serial buffer 
    //DEBUG_PORT.println(incomingByte);
    // Set the "fix" LED to on or off
    bool gpsWasFixed = fix.valid.status && (fix.status >= gps_fix::STATUS_STD);
    digitalWrite(fixLEDPin, gpsWasFixed);

    // When we have a valid location, print the latitude and longitude to the USB Serial terminal
    if (fix.valid.location)
    {
      DEBUG_PORT.println("The fix's location is valid!");
      DEBUG_PORT.print("     Latitude: ");
      DEBUG_PORT.println(fix.latitudeL());
      DEBUG_PORT.print("     Longitude: ");
      DEBUG_PORT.println(fix.longitudeL());
    }
    digitalWrite(fixLEDPin,HIGH);
  } // gps.available while loop
    digitalWrite(fixLEDPin,LOW);
  if(millis() - last_batt > 10000){
      delay(150);
      batt = analogRead(34);
      Serial.print("Batt: ");
      float batt_volt = map(batt, 720,1120,3000,4200)/1000.0;
      Serial.print(batt_volt);
      Serial.print("V  ");
      Serial.println(batt);
      last_batt = millis();
      gpsPort.println(F("$GPRMC,092751.000,A,5321.6802,N,00630.3371,W,0.06,31.66,280511,,,A*45"));
    }
  
} // loop()