As the subject says, I have a program on the Arduino MKR NB 1500 board using the SARA-R410M-02B LTE device that successfully sends SMS messages using the CMGS command. If I watch the AT commands in the terminal window it works as expected. After the CMGS command with my destination phone number I receive a '>' prompt for my text string. In version 5.06 and 5.08 of the SARA 410m firmware it immediately accepts my message and sends it to the destination.
In the version 5.12 firmware that I installed a couple of days ago this is no longer true. I receive the '>' prompt after the CMGS command, however, the CTRL-Z no longer accepts the message. The modem stays in message input mode. If I substitute an ESC character for the control-z, as expected, the input aborts and the program continues without having sent a message.
Has anyone else seen this issue? Is there a workaround?