GPS on the Thingy91

[Will Lizardo]

Hi,

I am trying to get the GPS from my thingy91, but it is not working. I can see that the board has CAT-M1 connection when I press the top button to get the GPS signal (therefore the main LED starts to blink purple), the Link Monitor shows that the board is trying to get GPS data, but it is not showing on the NRF Cloud.

I have tried with two different SIM Cards (iBASIS and local Vodafone) because I have heard that the PSM mode was not working on roaming sims, but it is still not working. Also, I have tried with an external antenna, but it did not work either. Any tips?

[Bjørn Kvaale]

Yep, this is related to PSM. Does Vodafone support LTE-M1 in New Zealand? Do you need to give in any APN code for that SIM? The problem is that even though the log says PSM mode is enabled, it really is not most likely. Do you also have a 91 DK or only a Thingy:91? Do you have a J-Link that you could program the Thingy:91 with?

If you have a 91 DK, I would flash the DK with the at client example, then run the following commands:

AT+CEREG=5
AT+CPSMS=1,"","","10101010","00100001"
AT+CEREG?

From the Active Time & Periodic TAU output values, you should be able to see if PSM is enabled or not.

It may also be that Vodafone does not support the current PSM interval. If that is the case, once you find a PSM time that works (try a few different values), update the Thingy code to reflect this change.

From the documentation, I found this. Not sure if this applies to Vodafone, but I would maybe also double check with them on PSM values that are allowed.

As long as you are testing on a window sill or outside, you should not need to use an external antenna. 

[Bjørn Kvaale]

Update: It may also be a good idea to download the Thingy FW hex file from here if needed. The thingy91_at_client.hex file should work fine if you want to test AT commands on the Thingy:91. You will still need some sort of J-Link with a 10 pin SWD cable to program the Thingy.