MC7700(AT&T) QMI, Call Failed

IoT Modules MC/EM Series
1

Hello,

I am using module MC7700(for AT&T) in our router. We have to use firmware version SWI9200X_03.05.20.03ap because of PTCRB. When I am trying to connect to network by QMI_WDS_START_NETWORK_INTERFACE(0x0020) I got error “Call Failed(14)” and error codes 12, 204. When I was using the firmware SWI9200X_03.00.05.04AP I did not have this problem. I found, when I switch module by AT!SELRAT to UMTS/HSPA, module will connect to 3G network without problems. When I switch module back to automatic selection(AT!SELRAT=0), module will connect to LTE network and is working well from this time. Have you ever seen this behavior?

Thanks for answers.

Jan

2

ohh strange…

have not seen this behavior…

Did u see any long gap after you have sent the QMI message before that error came?
also, in the FW SWI9200X_03.05.20.03ap, did everything worked fine when u do !selrat settings?

Not sure, but may be u need to set selrat… need to check this…

I think this QMI message maps to SLQSStartStopDataSession API… can you try to use Linux SDK and see whether the same issue is coming or not… just to verify…

3

Hello,

in the attachement you can see log file from our device.

Did u see any long gap after you have sent the QMI message before that error came?
Yes, it take about 10s between request and error.

2014-04-29 00:01:23 usbd[1000]: usbd started
2014-04-29 00:01:23 usbd[1000]: establishing connection
2014-04-29 00:01:23 usbd[1000]: sent [00 01 00 20 00 16 00 14 09 00 62 72 6F 61 64 62 61 6E 64 16 01 00 03 17 00 00 18 00 00]
2014-04-29 00:01:33 usbd[1000]: rcvd [02 01 00 20 00 13 00 02 04 00 01 00 0E 00 10 02 00 0C 00 11 04 00 02 00 CC 00]
2014-04-29 00:01:33 usbd[1000]: result is 14
2014-04-29 00:01:33 usbd[1000]: connection error: code 12,204

We use AT!SELRAT=0 in default, but factory fresh module not work with this settings. When I set SELRAT to UMTS/HSPA(I do not remember the number), router will connect to 3G network. When I set SELRAT back to 0, router is able to connect to LTE without problems. Module is working forever from this time.

I found similar behaviour when I use command AT!SCLTEPROF:

Default value is 1 and module is not able to connect to network. When I set SCLTEPROF to 2, module will connect to newtork. After that I can set SCLTEPROF back to 1 and module is still able to connect…

In the log file you can see whole sequece of AT & QMI commands we use. Maybe you will see what is missing or bad.
SPECTRE-LTE.log (6.7 KB)

4

Does it help to attach manually to the LTE network first, using QMI_NAS_INITIATE_ATTACH?

5

Hello,

I have just tried it, but I got result code 0x1A - QMI_ERR_NO_EFFECT(Does not matter if I use attach or detach)

Jan

6

I found solution of my problem. When I set APN and authentication type in “AT&T Mobile” profile(by QMI_WDS_MODIFY_PROFILE_SETTINGS), module is able to connect to network. I do not understand why is neccessary to do that, because in the QMI_WDS_START_NETWORK_INTERFACE message I am giving the same values to module. But without modifing the profile module is not able to connect.