GPS module does not update position after initial GPS location is fetched


I am using this GPS module together with an Arduino MKR GSM 1400. It is able to print the current position successfully but it doesn’t update over time. It only ever displays the initial value, even though the device has been moved. If I restart it, then it shows a new position. I’ve tried looking this issue up, both here and in other places, but I wasn’t able to find anything relevant. Would it be smart to use TinyGPS instead, or is it something obvious I’m doing wrong with my code?

I’m more or less doing precisely what one of the examples for the Adafruit GPS library shows, see this. Is it not meant to update the position over time?

Thanks in advance!

GPS should certainly update over time unless yours has some whacky configuration (that I’ve never heard of).

Tiny GPS is a good idea, but often you will see a suggestion that first you just echo everything from the GPS to the Serial monitor so you can see what it’s doing.

Yes, I don’t think the GPS module itself is to blame. Is it not more likely that something is not correct with the code I’ve written?

I’ve tried echoing everything from the GPS to the serial monitor, but I find it very difficult to read.

While the example I initially linked is what I am using, perhaps it would be better to provide context. Here is the code on GitHub. The 2-second timer is timed outside the get_position function, but it should be the same.

Does the GPS antenna can “see” the satellites or the ceiling of your room only ? :nerd_face:

If you believe it’s your code, I suggest that you do indeed switch over to a version TinyGPS and let it take care of it.

In general, avoid the Adafruit libraries. They are bloatware, and in the case of the GPS library, I know of a couple of serious problems.

TinyGPS++ and NeoGPS are much preferred.

Could be a problem with the code you are using.

But unless you show us the code you are using, who can tell ?

I’ve moved the Arduino outside, several kilometres, without it registering the update.

I did post a link to the code, here it is again :slight_smile:

It would be a good idea to post the code here, on the forum, so that links to unknown and potentially very dodgy sites do not have to be followed.

I see your point, but I thought most people considered GitHub safe, and not a dodgy website :slight_smile:

This is basically the GPS code. The loop function is called continuously. The get_position function is only called every other second or so. The GSM functionality of the Arduino MKR GSM is used to send the position to an API.


#include <Adafruit_GPS.h>
#include <tuple>

// what's the name of the hardware serial port?
#define GPSSerial Serial1

// Connect to the GPS on the hardware port
Adafruit_GPS GPS(&GPSSerial);

// Set GPSECHO to 'false' to turn off echoing the GPS data to the Serial console
// Set to 'true' if you want to debug and listen to the raw GPS sentences
#define GPSECHO false

class Positioning {
  void setup() {
    // 9600 NMEA is the default baud rate for Adafruit MTK GPS's- some use 4800
    // uncomment this line to turn on RMC (recommended minimum) and GGA (fix
    // data) including altitude
    // uncomment this line to turn on only the "minimum recommended" data
    // For parsing data, we don't suggest using anything but either RMC only or
    // RMC+GGA since the parser doesn't care about other sentences at this time
    // Set the update rate
    GPS.sendCommand(PMTK_SET_NMEA_UPDATE_1HZ); // 1 Hz update rate
    // For the parsing code to work nicely and have time to sort thru the data,
    // and print it out we don't suggest using anything higher than 1 Hz

    // Request updates on antenna status, comment out to keep quiet


    // Ask for firmware version

  bool loop() {
    // read data from the GPS in the 'main loop'
    char c =;
    // if you want to debug, this is a good time to do it!
    if (GPSECHO) {
      if (c) {
    // if a sentence is received, we can check the checksum, parse it...
    if (GPS.newNMEAreceived()) {
      // a tricky thing here is if we print the NMEA sentence, or data
      // we end up not listening and catching other sentences!
      // so be very wary if using OUTPUT_ALLDATA and trying to print out data
      // this also sets the newNMEAreceived() flag to false
      // Serial.print(GPS.lastNMEA());
      if (!GPS.parse(GPS.lastNMEA())) { // this also sets the newNMEAreceived()
                                        // flag to false
        return false; // we can fail to parse a sentence in which case we should
                      // just wait for another
    return true;

  struct position {
    float lat, lon;
    bool success;

  struct position get_position() {
    Serial.print("\nTime: ");
    if (GPS.hour < 10) {
    Serial.print(GPS.hour, DEC);
    if (GPS.minute < 10) {
    Serial.print(GPS.minute, DEC);
    if (GPS.seconds < 10) {
    Serial.print(GPS.seconds, DEC);
    if (GPS.milliseconds < 10) {
    } else if (GPS.milliseconds > 9 && GPS.milliseconds < 100) {
    Serial.print("Fix: ");
    Serial.print(" quality: ");
    if (GPS.fix) {
      Serial.print("Location: ");
      Serial.print(GPS.latitudeDegrees, 4);
      Serial.print(" ");
      Serial.println(GPS.longitudeDegrees, 4);
      Serial.print("Speed (knots): ");
      Serial.print("Angle: ");
      Serial.print("Altitude: ");
      Serial.print("Satellites: ");

      return position{GPS.latitudeDegrees, GPS.longitudeDegrees, true};

    // no position could be fetched
    return position{0, 0, false};

Some might, but to work out it was a ‘Github’ link you have to hover the mouse cursor over the link as it was was disguised, to see where it actually is pointing to.

Remember the forum members here are volunteers , so make things easy for them.

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