how can i edit the code to get it to flip flop gps units… show 1, then 2, then 1, then 2?
Hi there,
Sure Try this one , it does each one every time through the loop after the serial poll t see if anything is available.
#include <TinyGPSPlus.h>
#include <SoftwareSerial.h>
#include <HardwareSerial.h>
// ------------------ GPS Configurations ------------------
// For GPS 1 (HardwareSerial on UART1)
const int gps1RXPin = 9; // Connect GPS1 TX to ESP32 RX (pin 9)
const int gps1TXPin = 10; // Connect GPS1 RX to ESP32 TX (pin 10)
const uint32_t gps1Baud = 9600;
// For GPS 2 (SoftwareSerial)
// Using pins D7 and D6 for GPS 2 (as defined in your example)
const int gps2RXPin = D7; // Connect GPS2 TX to ESP32 RX (pin D7)
const int gps2TXPin = D6; // Connect GPS2 RX to ESP32 TX (pin D6)
const uint32_t gps2Baud = 9600;
// ------------------ Objects ------------------
TinyGPSPlus gps1; // For HardwareSerial GPS
TinyGPSPlus gps2; // For SoftwareSerial GPS
// Use UART1 for GPS 1:
HardwareSerial SerialGPS1(1);
// Use SoftwareSerial for GPS 2:
SoftwareSerial SerialGPS2(gps2RXPin, gps2TXPin); // (RX, TX)
// ------------------ Global Variables ------------------
// A flag to alternate between GPS units on each update.
bool useGps1 = true;
// ------------------ Function Prototypes ------------------
static void smartDelay(unsigned long ms);
static void printFloat(float val, bool valid, int len, int prec);
static void printInt(unsigned long val, bool valid, int len);
static void printDateTime(TinyGPSDate &d, TinyGPSTime &t);
static void printStr(const char *str, int len);
void setup() {
Serial.begin(9600);
delay(2000);
Serial.println("\nFullExample.ino");
Serial.println("An extensive example of many interesting TinyGPSPlus features");
Serial.print("Testing TinyGPSPlus library v. ");
Serial.println(TinyGPSPlus::libraryVersion());
Serial.println("by Mikal Hart, tweaked for 2 GPS by PJG");
Serial.println();
Serial.println("Sats HDOP Latitude Longitude Fix Date Time Date Alt Course Speed Card Distance Course Card Chars Sentences Checksum GPS");
Serial.println(" (deg) (deg) Age Age (m) --- from GPS ---- ---- to London ---- RX RX Fail");
Serial.println("----------------------------------------------------------------------------------------------------------------------------------------");
// Initialize GPS 1 (HardwareSerial) on UART1 with assigned pins.
SerialGPS1.begin(gps1Baud, SERIAL_8N1, gps1RXPin, gps1TXPin);
Serial.println("GPS-1 GooUUU Tech GT-U7 HardwareSerial initialized on pins 9 (RX) and 10 (TX).");
// Initialize GPS 2 (SoftwareSerial) on pins D7 & D6.
SerialGPS2.begin(gps2Baud);
Serial.println("GPS-2 GooUUU Tech GT-U7 SoftwareSerial initialized on pins D7 (RX) and D6 (TX).");
Serial.println();
}
void loop() {
// Process incoming GPS data for both GPS units.
while (SerialGPS1.available() > 0) {
char c = SerialGPS1.read();
gps1.encode(c);
}
while (SerialGPS2.available() > 0) {
char c = SerialGPS2.read();
gps2.encode(c);
}
// Instead of choosing based on validity or age, we alternate.
TinyGPSPlus* activeGps;
if (useGps1) {
activeGps = &gps1;
} else {
activeGps = &gps2;
}
// Print output using the active GPS data:
printInt(activeGps->satellites.value(), activeGps->satellites.isValid(), 5);
printFloat(activeGps->hdop.hdop(), activeGps->hdop.isValid(), 6, 1);
printFloat(activeGps->location.lat(), activeGps->location.isValid(), 11, 6);
printFloat(activeGps->location.lng(), activeGps->location.isValid(), 12, 6);
printInt(activeGps->location.age(), activeGps->location.isValid(), 5);
printDateTime(activeGps->date, activeGps->time);
printFloat(activeGps->altitude.meters(), activeGps->altitude.isValid(), 7, 2);
printFloat(activeGps->course.deg(), activeGps->course.isValid(), 7, 2);
printFloat(activeGps->speed.kmph(), activeGps->speed.isValid(), 6, 2);
printStr(activeGps->course.isValid() ? TinyGPSPlus::cardinal(activeGps->course.deg()) : "*** ", 6);
// Example reference: using Pittsburgh coordinates.
static const double PITTSBURGH_LAT = 40.4406, PITTSBURGH_LON = -79.9959;
unsigned long distanceKmToPittsburgh =
(unsigned long)TinyGPSPlus::distanceBetween(
activeGps->location.lat(),
activeGps->location.lng(),
PITTSBURGH_LAT, PITTSBURGH_LON) / 1000;
printInt(distanceKmToPittsburgh, activeGps->location.isValid(), 9);
double courseToPittsburgh =
TinyGPSPlus::courseTo(
activeGps->location.lat(),
activeGps->location.lng(),
PITTSBURGH_LAT, PITTSBURGH_LON);
printFloat(courseToPittsburgh, activeGps->location.isValid(), 7, 2);
const char *cardinalToPittsburgh = TinyGPSPlus::cardinal(courseToPittsburgh);
printStr(activeGps->location.isValid() ? cardinalToPittsburgh : "*** ", 6);
printInt(activeGps->charsProcessed(), true, 6);
printInt(activeGps->sentencesWithFix(), true, 10);
printInt(activeGps->failedChecksum(), true, 9);
// Print additional column indicating source: "GPS 1" or "GPS 2".
Serial.print(" ");
if(activeGps == &gps1) {
Serial.print("GPS 1 - GT-U7 ");
} else {
Serial.print("GPS 2 - GT-U7 ");
}
Serial.println();
// Alternate the active GPS for the next update.
useGps1 = !useGps1;
smartDelay(1000);
if (millis() > 5000 && activeGps->charsProcessed() < 10)
Serial.println(F("No GPS data received: check wiring"));
}
static void smartDelay(unsigned long ms) {
unsigned long start = millis();
do {
while (SerialGPS1.available() > 0)
gps1.encode(SerialGPS1.read());
while (SerialGPS2.available() > 0)
gps2.encode(SerialGPS2.read());
} while (millis() - start < ms);
}
static void printFloat(float val, bool valid, int len, int prec) {
if (!valid) {
while (len-- > 1)
Serial.print('*');
Serial.print(' ');
} else {
Serial.print(val, prec);
int vi = abs((int)val);
int flen = prec + (val < 0.0 ? 2 : 1); // for decimal point and possible '-'
flen += vi >= 1000 ? 4 : vi >= 100 ? 3 : vi >= 10 ? 2 : 1;
for (int i = flen; i < len; ++i)
Serial.print(' ');
}
smartDelay(0);
}
static void printInt(unsigned long val, bool valid, int len) {
char sz[32] = "*****************";
if (valid)
sprintf(sz, "%ld", val);
sz[len] = 0;
for (int i = strlen(sz); i < len; ++i)
sz[i] = ' ';
if (len > 0)
sz[len - 1] = ' ';
Serial.print(sz);
smartDelay(0);
}
static void printDateTime(TinyGPSDate &d, TinyGPSTime &t) {
if (!d.isValid()) {
Serial.print(F("********** "));
} else {
char sz[32];
sprintf(sz, "%02d/%02d/%02d ", d.month(), d.day(), d.year());
Serial.print(sz);
}
if (!t.isValid()) {
Serial.print(F("******** "));
} else {
char sz[32];
sprintf(sz, "%02d:%02d:%02d ", t.hour(), t.minute(), t.second());
Serial.print(sz);
}
printInt(d.age(), d.isValid(), 5);
smartDelay(0);
}
static void printStr(const char *str, int len) {
int slen = strlen(str);
for (int i = 0; i < len; ++i)
Serial.print(i < slen ? str[i] : ' ');
smartDelay(0);
}
HTH
LMK
GL 
PJ 
Film at 11…
Enjoy.