We have recently purchased a Sodaq Explorer with the NB-IoT shield.
Currently we are trying via the official documentation (AT Commands) to connect it to COSMOTE NB-IoT network (Greek Mobile Operator).
So far we have succeeded to connect it to the NB-IoT enabled Base Station, register it to the network and get an IP.
However when we are trying to start a UDP socket (AT+NSOCR=“DGRAM”,17,16666,0) so as to communicate with the backend server we get Error mesages without further explanation. Errors also appear when we are trying to ping our backend server and 126.96.36.199, both of which have been properly forwarded and are accessible through the other NB-IoT connected devices.
The command succession is the following:
AT+NRB AT+CFUN=0 AT+NCDP="xxx.xxx.xxx.xxx" AT+CGDCONT=0,"IP","xxx" AT+CFUN=1 AT+NBAND=20 AT+COPS=1,2,"xxxxx" AT+CSQ AT+CGATT? AT+CGPADDR" AT+NSOCR="DGRAM",17,16666,0 AT+NPING="188.8.131.52"
So the errors occur at the last two commands, we suspect that it has nothing to do with the network config, but maybe with the board itself, so the question would be if someone has experienced something similar, and if the board/firmware is to blame, where can we download new firmware (the chipset is SARA-N211 v 02B-00)
Thank you in advance and sorry for the long post!