Quote from: peejster on May 26, 2014, 05:36:55 PM
Unable to get a reading from the GPS TinyShield. I've read the documentation for the GPS TinyShield as well as the notes from the TinyGPSPlus library. I have the TinyDuino board at the bottom, then the GPS TinyShield on top of the processor, and then the TinyShield USB & ICP board on top of the GPS.

I ran the Blink sketch successfully to ensure that everything was working properly. (From the IDE, the board I have selected is Arduino Pro or Pro Mini (3.3V, 8MHz) with ATmega328.)

To test the GPS, I used the setup from the example provided in the Tiny-Circuits site and then I used a simplified loop just to get some readings. However, I always seem to get the "No GPS detected" message. I also wasn't sure exactly which pin A0 or A1 is the RX pin on the GPS TinyShield - the example code has RX as A1 but the text above th example code on the Tiny-Circuits GPS tutorial states that RX is A0. I tried it both ways - same result.

I can't figure out why I am not getting any readings.

Code Select Expand

#include <TinyGPS++.h>
#include <SoftwareSerial.h>
/*
   This sample code demonstrates the normal use of a TinyGPS++ (TinyGPSPlus) object.
*/
static const int GPS_ONOFFPin = A3;
static const int GPS_SYSONPin = A2;
static const int GPS_RXPin = A0;
static const int GPS_TXPin = A1;
static const int GPSBaud = 9600;

// The TinyGPS++ object
TinyGPSPlus gps;

// The serial connection to the GPS device
SoftwareSerial ss(GPS_RXPin, GPS_TXPin);

void setup()
{
  Serial.begin(115200);
 
  // Init the GPS Module to wake mode
  pinMode(GPS_SYSONPin, INPUT);
  pinMode(GPS_ONOFFPin, OUTPUT);
  digitalWrite( GPS_ONOFFPin, LOW );   
  delay(5);
  if( digitalRead( GPS_SYSONPin ) == LOW )
  {
    // Need to wake the module
    digitalWrite( GPS_ONOFFPin, HIGH );
    delay(5);
    digitalWrite( GPS_ONOFFPin, LOW );     
  }

  ss.begin(GPSBaud);
}

void loop()
{
  while (ss.available())
    if (gps.encode(ss.read()))
    {
      Serial.print(F("Location: "));
      Serial.print(gps.location.lat(), 6);
      Serial.print(F(","));
      Serial.print(gps.location.lng(), 6);
    }
   
  if (millis() > 5000 && gps.charsProcessed() < 10)
  {
    Serial.println(F("No GPS detected: check wiring."));
    while(true);
  }
}

It sounds like you've put a lot of effort into troubleshooting the issue with your GPS TinyShield. Since you've checked the hardware setup and reviewed the code, here are a few additional suggestions: Double-check the wiring connections to ensure they're secure and accurate, confirm the power supply to the GPS TinyShield is stable, and make sure the antenna has a clear view of the sky for satellite signals. Additionally, try using serial debugging tools to check for any errors or data reception from the GPS module. If the problem persists, consider reaching out to Tiny-Circuits support for further assistance. Keep testing in different environments to rule out external factors, and hopefully, you'll have the GPS module working soon. Kitchens Parramatta