Getting started with the Thingy:91

[Calin M]

Trying to get started with the Thingy:91

- It's connecting to NRF Cloud and reporting data.

Problems:

1. Keeps blinking blue and does not get a GPS lock. I did leave it near the window. I did hold down the button for more than 10 seconds as suggested in another post, to turn on the GPS. I'm in Vancouver, Canada and using the iBasis SIM. How would I find out if this is because my provider does not support power saving mode?

2. Is the LTE Link monitor supposed to work over USB? I connected it via USB but I get "No devices available". I did uncheck auto device port filter.

I don't have a NRF9160 DK.

Thanks!

Calin

[Calin M]

Hi Didrik,

I tested it with both the iBasis and with the hologram sim, and the GPS does not work. I understand from some other post that PSM Enabled in the log does not mean that PSM is actually enabled.

I called the local network operator (Rogers) and it's impossible to get a support person that understands the problem. This is all very new to them, and they don't care enough to provide support to roaming customers.

I wonder if  iBasis Tech Support has any insight into why PSM mode is not working on the Rogers network in Canada. Is it working anywhere in the world when roaming with an iBasis card?

Thanks,

Calin

[Calin M]

Does this mean that it's in PSM mode?

[Calin M]

./applications/asset_tracker/build_folder/zephyr/.config:CONFIG_LTE_PSM_REQ_RPTAU="00000110"
./applications/asset_tracker/build_folder/zephyr/.config:CONFIG_LTE_PSM_REQ_RAT="00000000"

Could it be the case that other values for these parameters would work on more networks? In particular, should CONFIG_LTE_PSM_REQ_RAT be all zeros?

Thanks!

[Calin M]

Hi Didrik Rokhaug

Is there a way to enable some debugging in the asset tracker, or run some AT commands and show that the network operator does not support the PSM? PSM is one of the selling features of LTE-M, I find it hard to imagine they turned it off.

Thanks,

Calin

[Didrik Rokhaug]

Hi, and sorry for the slow response, but due to the TechTour and some sickness we are a bit short on staff with nRF91 experience at the moment.

If I understand correctly, the Hologram SIM card is also roaming? If so, I would expect the performance to be similar to the iBasis SIM card.

The +CPSMS command lets you set and read the requested timer values, and can therefore not be used to check whether those values got accepted.

If you do not get any log messages between the "Searching for satellites [...]" and "Stopping GPS. The device will try again [...]" to my knowledge that means that it has not entered PSM.

For how to check if you are in PSM, you might be able to use the +CEREG with response type 4 or 5, or the %XMONITOR. What we are interested in is the Active-Time and Periodic-TAU values. However, I am currently working on another case which reports some problems with the %XMONITOR command, that probably also includes the +CEREG command.

I will keep you informed about any progress I make.

Best regards,

Didrik