Important update regarding LTE modem updates

[le_wildfox]

@xykon Thank you for updating us.
Does the "unresponsive" -ness symptoms include intermittent successful register & attach attempts?

I did connectivity tests at Vodafone UK nb-iot lab (Huawei equipments) using GPy with 37781 NB-IoT FW version. Registrations to nb-iot network were failed using the example sequence as in example neither via REPL nor putting it in the script.

Slight modification to the example as below snippet worked several times:

print("Trying to connect to nb-IoT network...")
send_at_cmd_pretty('AT+CFUN=0')
time.sleep(3)
send_at_cmd_pretty('AT+CFUN=0')
time.sleep(5)
send_at_cmd_pretty('AT+CFUN=1')
time.sleep(2)
send_at_cmd_pretty('AT!="clearscanconfig"')
time.sleep(2)
send_at_cmd_pretty('AT!="addscanfreq band=8 dl-earfcn=3730"') #band & earfcn
time.sleep(2)
send_at_cmd_pretty('AT!="zsp0:npc 1"')
time.sleep(2)
send_at_cmd_pretty('AT+CEREG=2')
time.sleep(1)
send_at_cmd_pretty('AT+CGDCONT=1,"IP","vdf"') #apn
time.sleep(1)

However, register & attach attempts were only intermittently successfull, either success to register or failed with AT+CEREG? returned 2,4 (4 --> unknown cause).

At some point, the device flash memory seemed to be wiped by itself, all the scripts were gone. After this event, connection attempts were always failed with AT+CEREG? returned 2,4.

Any lights to this issue?

Cheers!

[sh4nnongoh]

@xykon Thank you, looking forward to this. Yes, please have an "unbrick procedure" as well. What are the 2 issues that cause the brick? I am not sure if mine is bricked or not.

[Prawnhead]

Very glad to hear you've replicated the issue and have a fix underway. The icing on the cake would be if you can come up with an "unbrick procedure" too :) Thanks for all you do. We love Pycom stuff!