AW: text mode SMS

Ralf Glaser glaser at
Mon Nov 15 09:15:28 UTC 2021


after further investigation i finally found the problem. First of all you are perfectly right text/pdu mode is not the issue here. The actual issue was that mmcli sends SMS from a file in 8-bit encoding while message text given on the command line is send in 7-bit encoding.
The recipient selects AT+CSCS="GSM" and the modem in use (don't know which one it is) then falls back to AT+CSCS="HEX" automatically which at first glance looked like a PDU mode SMS in the log files.

Is there an option to select the character encoding when using mmcli?

Best regards,

Von: Aleksander Morgado <aleksander at>
Gesendet: Mittwoch, 10. November 2021 13:08
An: Ralf Glaser <glaser at>
Cc: modemmanager-devel at <modemmanager-devel at>
Betreff: Re: text mode SMS


> No, that's not the problem, if our gateway is also used for receiving SMS we can easily do the conversion in software, the problem is that there are historical devices (e.g. GSM modems) in use that cannot be replaced.

But what I mean here is that just changing the way an SMS is created
in the sender device (via text mode or pdu mode) would not change the
way the target device receives the SMS (in pdu mode).

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the ModemManager-devel mailing list