How to install at_client to Thingy:91?

[Yusuke]

I got Thingy:91 and want to install at_client to it, but it doesn't work well.

What I did is

1. Check out a pull request  and update firmware referring to this link

2. Connect j-link and usb to Thingy:91.

3. Open LTE Link Monitor.

It always restarts and never accepts at command.

Any tips?

[Hoang]

hi Yusuke, 

Have you tried to flash at_client.hex for your THINGY:91? 

You can try: 

Use nRF91DK and Connect the Thingy:91 to the nRF9160DK board’s “Debug out” port using a 10-pin JTAG cable. 

And, try to flash the: thingy91_at_client.hex

You can read more on this link

Hope it can help

Hoang Nguyen

[Yusuke]

Hi, Hoang, thank you for your comment.

Do I have to use nRF9160 DK board to flash at_client firmware to Thingy:91?

That's inconvenient.

[Heidi]

Hi, can you confirm that you don't have the COM port (13) open in another program or another window. You could be getting access denied because you're only allowed to have a COM port open in one place.

Best regards,

Heidi

[Yusuke]

>can you confirm that you don't have the COM port (13) open in another program or another window.

I confirmed about it. There is no other program opening the COM port(13)

[Heidi]

Hi, thanks for confirming.

Could you try this:

1. Erase the firmware with

nrfjprog -e

2. Switch the device off and on

3. Flash the example again

[Yusuke]

I did this but doesn't work unfortunately.

It works right after fw is installed but never works if I switch off and on or refresh LTE Link monitor

[Heidi]

Hm, okay. The Thingy:91 is a little unstable, so my best advice would be to just keep repeating switching the device off and the on again, refreshing LTE Link Monitor and trying to connect. Make sure you have unchecked "Auto device/port filter" in the bottom right corner of the program then select one of the COM ports which "PCA20035". Only one of them is the modem so try both for a while.