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11 months, 3 weeks ago.
Why is the C030-N211 board running with a wrong AT Command but not without it?
I've got a problem with the C030-N211 NB-IoT board. I'm trying to implement a simple ping pong with the board as the device and a local UDP server.
I am using a 1NCE SIM card and the mbedOS library, especially the ATCmdParser, to work with the AT commands.
The tests of my implementation have been successful and I was able to communicate with the server and vice versa using the following AT command:
AT command in line 4 is wrong but still needed
//initalizing network settings at->send("AT+NPIN=0,\"12345\""); at->send("AT+CFUN=1"); at->send("AT+CFDCONT=1,\"IP\",\"iot.1nce.net\""); at->send("AT+NBAND=8"); at->send("AT+COPS=1,2,\"26201\",7"); //checking if connection has been established at->send("AT+CEREG?"); at->send("AT+COPS=?"); //creating a socket and sending a UDP message at->send("AT+NSOCR=\"DGRAM\",17,19019,1"); at->send("AT+NSOST=0,\"10.11.12.13\",1912,4,\"70696E67\"");
This was successful and I was able to send and receive messages. But when cleaning up my code I realized that I had a spelling mistake in the third AT command ("AT+CFDCONT" instead of "AT+CGDCONT"). I corrected this and tested the implementation once again and realized that it was not working anymore.
After multiple test, e.g. sending absolut nonsense as an AT command, I came to the conclusion that a "wrong" command is required between CFUN and NBAND to get the code to work which is kind of strange behavior.
Does anyone have an idea what I am doing wrong or where this behavior may come from?
If some more informations, e.g. code, are needed I will try to give them if requested.