Hello,
starting a blank call is exactly the way I replicate the error.
I’m not interested in sending or receiving voice, but only DTMF, so the Base HAT capabilities are ok:
the Quectel module is able to send and recognize them with the command AT+VTS and AT+QLDTMF.
Unfortunately every time I start or receive a call, all the tty ports and the ethernet interface disappear.
For the operating system, the module is completely disconnected.
The poweroff-poweron cycle with the GPIO26 can restore the normal behaviour, but it should be an “emergency maneuver” only.
I don’t think the cause is the Quectel module, or the Rock PI X: I connected the Base HAT to a laptop (instead the Rock PI) using the USB, with a U-Blox module (instead the Quectel one) and the error is the same.
If you and other users can do some tests and share the results, I would appreciate it.
It could be my Base HAT faulty… ?