This codeblock assumes that a SIM can always store a total of 20 SMS. However, this isn't always the case. The output of AT+CPMS="SM" should be used to determine the maximum storage, since the HAT will raise an error if a slot that's too high is access ed.
https://github.com/Civlo85/gsmHat/blob/f8e4bf75f29f4c96926e3053e268f461ff3584cb/gsmHat/gsmHat.py#L540-L543
This codeblock assumes that a SIM can always store a total of 20 SMS. However, this isn't always the case. The output of
AT+CPMS="SM"should be used to determine the maximum storage, since the HAT will raise an error if a slot that's too high is access ed.