serial_lte_modem problem

[nordicNewbie]

Hello all,

I've got a Thingy 9.1. I've successfully built and flashed the serial_lte_modem example (with no changes) onto the device but when I open the serial port in LTE link monitor I get no response at all. I have reset, turned it off and on again, still nothing.

Unfortunately these instructions https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/applications/serial_lte_modem/doc/slm_description.html don't have any advice on what to do if I get no response.

I am programming over USB using nRF connect v3.6.0 programmer.

Thingy 9.1
PCA20035
1.0.0
2019. 43

When the asset tracker application is loaded, the serial port responds normally.

What have I done wrong?

[Heidi]

Hi!

The Serial LTE Modem application currently only supports the nRF9160 DK, not the Thingy:91. You will need to port the application before it can be run on the Thingy:91. 

Best regards,

Heidi

[nordicNewbie]

Is there pre-compiled firmware available that gives me access to the extended AT command set? I purchased this device because it claimed to have AT command access but now you are telling me that the extended AT commands aren't supported on the Thingy9.1.

Has anyone else ported the firmware across and can share the files?

[Heidi]

Hi!

The device does have AT command access, see the nRF91 AT Command Reference Guide.  However, the SLM propriety AT commands are not supported out-of-the-box on the Thingy:91.

I can see if someone else has ported the FW, and if not port it myself. Just give me a few days. :) 

Best regards,

Heidi

[nordicNewbie]

That would be perfect, thank you!

By the looks of things there are quite a few other people waiting for the same FW.

[Heidi]

Hi! I've been informed that my earlier comment was incorrect. Sorry about that.

The Serial LTE Modem sample should actually work on the Thingy:91, it's just not documented yet.

The Thingy:91 version 1.0.0 has an unstable USB connector, so you might need to turn the device off and on a few times and keep trying to connect. 

What modem firmware version is on the device?

I don't have a Thingy:91 in my home office right now, but I will try to get a hold of one tomorrow and test this out. 

Best regards,

Heidi

[nordicNewbie]

Do you mean the physical connector is dodgy? or the usb controller has a problem?
In either case, I believe if the USB connector or controller were the issue I wouldn't be able to connect to any samples/applicatoins or program any firmware over usb with mcuboot.

The modem firmware is mfw_nrf9160_1.0.1

I'm currently using win7 so I am installing everything to my win10 machine to see if there is any difference.

[nordicNewbie]

Moving to win10 didn't help, still no output on the usb.
Am I supposed to setup the comms/USB in the example? What changes are needed to get it to work on the thingy9.1?

[Heidi]

Could you try updating the FW on the nRF52840 to the connectivity bridge FW. And using the latest MFW version?

[nordicNewbie]

Is there updated firmware for the nRF52840? I updated the connectivity bridge but I am still not getting any response when I sent AT commands.

[Heidi]

The Thingy:91 doesn't come shipped with the connectivity bridge, but an older application, so if you've flashed the connectivity bridge you have updated the FW on the nRF52840.

I think I'll test this myself and get back you.