Possible library issue with GPS.fix not being released

[RoboticSith]

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Summary: I am using the EN pin on the Ultimate GPS Breakout V3 to simulate a loss of fix so I can test various parts of my code and circuitry. When I disable the module via this method after a fix has been established, the GPS.fix variable does not change to FALSE.

1. Connect GPS module to any of the above controllers.
2. Run parsing code for RMC & GGA sentences at 1Hz.
3. Wait for fix to be established, verify that GPS.fix is TRUE.
4. Connect the EN pin to GND, observe that the GPS module turns off yet GPS.fix remains TRUE.

GPS_ExtParse.txt

[drak7]

There's no way for the library to know that you're turning off the GPS module.
If you want to test a loss of fix you can manually set fix to false or feed fake sentences to the library with the appropriate fix value.
You could also use the secondsSinceFix method to see when the last fix was and set GPS.fix to false after a certain threshold.

[svdrummer]

You could use the tinygps++ library as this has a function to yest how old the nmea sentence is. If it is older than a few seconds, you can trap that in your code.

[RoboticSith]

Thanks for the feedback. I figured that the variable(s) behind the sentence contents would revert to their default/init values when the module was disabled since there wouldn't be any data behind them, I didn't think the previous sentence would stick around.

After posting this, I figured out that if I re-enabled the module briefly so it could send a handful of new sentences after having lost the fix (but not long enough to reacquire), everything in my code worked as expected. I'll try one of the suggested solutions if I run into testing issues in the future once I incorporate the backup battery.

Thanks again.

[caternuson]

Closing. Sounds resolved.