Recently i purchased an LTE Cat M1/NB-IoT Shield (CEL-14997) and i attempted use the library with it and it never loaded. I then decided to use a serial passthrough to see if i could get it to respond to AT commands or echo my replies but no response is sent back.
I used an arduino Uno aswell as well as an MSP430 (set it up to use the 6-pin header and have the the shield powered by the uno, attempted with the MSP430 aswell) and neither were able to get a response from it. Tried to use both software and hardware serial for both, i do know they can both talk to eachother without problems aswell.
I feel the SARA module or the logic level changer may be damaged.
Any ideas if i have set something up wrong? or could the device be faulty?
Not sure what board you are using, but maybe the following will help.
I have just been playing around with this LTE shield and an Arduino Mega and you can not plug the shield directly into the Mega, it will not work.
Sparkfun selected pins 8 & 9 to be the software serial pins, but if you look at the software serial documentation you will see that pins 8 & 9 on the Mega can not be used for software serial function https://www.arduino.cc/en/Reference/SoftwareSerial
So you need to pick two compatible pins and alter the standard code. Why Sparkfun didn’t attempt to make this compatible with Uno, Mega and Leonardo by using pins 10 & 11 as default is a bit :?: :?:
Therefore you need to connect the boards with jumper wires. When you have the shield connected with bits of wire don’t forget you also need to connect the cables 5 & 6 for the power & reset functions, again if you dont connect those the shield will not work.