Asset Tracker - GPS Fix LED

Getting Started
1

Hi. Stumbling further on this road... my next issue is confirming how the GPS Fix LED should work on the Asset Tracker shield.

This piece of advice is found on the Particle Datasheets section:
(https://docs.particle.io/datasheets/particle-shields/#using-the-asset-tracker)

When the GPS Fix LED is blinking once per second (1Hz) then it is trying to get a fix but does not yet have one. It will blink once per 15 seconds when it actively has a fix, and you can check that from code using the .gpsFix() function.

However, my Asset Tracker doesnt appear to behave like that. When placed in clear view of the sky the LED blinks once per second as described but then goes off (steady off, no blink at 15 sec intervals). If I bring it under cover (losing clear view of sky) the LED starts to blink at the 1 sec frequency, and this is repeatable.

I looked at the GPS chip datasheet: It says:

Pasted image1008×266 40 KB

Also the schematic for the shield at:

shows the GPS pin 5 (GPS 3d Fix pin) connected direct to the LED.
ie if pin is LOW LED is off.

So I wonder is the Particle Datasheet correct about the blink the GPS fix LED every 15 seconds when it has a fix? Does anybody have any specific experience that confirms or rebuts that piece of advice?

Thanks for your help.

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I haven’t got experience but I recall a thread that also reports this behaviour and this was confirmed correct behaviour - but docs haven’t been updated yet.
Asset Tracker GPS real-time google map

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Thanks @ScruffR. Yep, you are right. Really appreciate your ready supply of advice. Commentary was already there in the forum. Confirming after some experimentation (and using the Particle.Function feature in Dev) that when the GPS Fix LED is off that the GPS has a fix (this after a period of 1 sec on/off flashing whilst it gets a fix). The flash once per 15 seconds advice is not correct (just saying out loud to leave further breadcrumbs for those following).

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