GPS tracker does not get a fix

Using Arduino Project Guidance
#1

I have assembled the Arduino GPS ‘Track Your Treats’ tracker with an Arduino UNO board and the Adafruit GPS tracker shield.
I have found that it does work, i.e. the red led on the shield starts blinking once a second and after some time it blinks every fifteen seconds (when I have a clear view to the sky).
I believe that it has found a fix in that case.
When I go inside the house, the red starts blinking once a second again.

But there are no location entries in the file on the SD card, only the first line with the column headers.
The red LED on pin 5 keeps on blinking once a second, as far as I know this means ‘no fix yet’.
I do not find a proper ‘close file’ line of code, is that not necessary?
When I put the SD card in my laptop I see several files, but all with only the header line.

Thanks for reading this and I hope you do have a solution for me.
Dick van Fulpen, Houten (NL)

#2

Not enough information. Please read "How to use this forum" and follow the directions.

However, I can suggest that you print out the GPS messages received, so that you can be certain that a fix has been obtained. Also note that SD card data is buffered, and nothing is written to the card until a buffer has been filled.

#3

Glad to hear and help but as describing your problem you understand that we need code and it's a code problem,
would be better to give us a full view of your side, connections (pinds), components and code to understand how exactly you use it.

D.60

#4

Thanks for the reply.
I have assembled the system exactly as instructed by the designer Tony Dicola and did not change the code of the sketch, see Overview | Track Your Treats: Halloween Candy GPS Tracker | Adafruit Learning System.
There you will find hard- and software details.

The red LED on the shield suggests I do get a fix, but the LED connected to data output 6 keeps on blinking.
This is part of the sketch:
...
void loop() {
// Parse GPS messages when they are received.
if (GPS.newNMEAreceived()) {
GPS.parse(GPS.lastNMEA());
}
// Light the LED solid if there's a GPS fix, otherwise flash it on and off once a second.
if (GPS.fix) {
digitalWrite(LED_PIN, HIGH);
}
else {
// No fix, blink the LED once a second and stop further processing.
digitalWrite(LED_PIN, (millis()/1000) % 2);
return;
}
// Check if the button is pressed.
...
So if the LED on output 6 keeps blinking, there is not a fix.
I think of commenting out the line 'return' to see what happens.
Or perhaps the function GPS.fix works a bit differently than expected?
I must say that I have installed the latest IDE (version 1.6.5) and the software for the SD module.

#5

Problem solved: the tiny switch on the GSP shield must be switched to 'Soft Serial' to log the locations.
So it does work after all!
Kind regards, Dick van Fulpen, Houten (NL)

#6

Glad to hear you solved the problem,
sad that I couldn't reply, I had few weeks off arduino.

D.60

#7