Accessing the modem for AT commands / voice?

[k7paul]

Hi all,

Could anyone please point me to some documentation on how Ubuntu Touch handles voice and AT commands for the in-built modem on OnePlus 5T?

I have discovered /dev/ttyMSM0 and /dev/ttyHS0 but they don't seem to respond to AT commands when connected via minicom.

Why?:
I would like to install asterisk and try to make a VoIP bridge out of the phone. For this I would like to know how the internal modem routes the audio (I can see there are a few 50 alsa devices on the system, seemingly linked to the MSM device :-S) and how to communicate with the modem to read SMS etc.

Thank you!