I use the original library Arduino GSM
but I wish I could still send AT commands.
for functions that are not in the library,
is it possible.
thank you in advance...
If you know in what states the GSM module is when you use the original library and in what states you can use your intended AT commands then it is possible. Finally it will depend on the AT commands you will use.
My experience is that there are AT commands which only work when the GSM module is in a "suitable state". Until now I could not find a document or forum posts describing the possible states of the GSM module. Especially I am missing information what to do when the GSM module reports errors or does not respond like expected. If you have knowledge about this please tell me the sources.