I am working with a B-L072Z-LRWAN1 board and a 8pya00-simcom-evb v1.02 board with SIM7000E. This SIM module operates through AT commands and I need to send these commands through an UART connected between mentioned boards.
I have already set up the UART in the B-L072Z-LRWAN1 and I am able to transmit bytes of information, but I am not sure how to send AT commands.
Which is the format I have to use to send the commands? Do I use char variables? Do I use uint8_t variables and add '0' at the end to make them chars? Do I need to add \n\r at the end of the command?
I am a little bit confused so I need your help.
Thank you!
Best Answer
char
anduint8_t
should be equivalent on ARM, in other words,char
should beunsigned
, but there are toolchains out there withchar
by default signed. It does not matter in this case anyway, becauseAT
commands would only use characters in the [0-127] range.Adding a
\r
at the end of the command is mandatory,\n
and\x00
would probably be ignored, but better not send them. Responses are terminated with\r\n
(not\n\r
)