I have read that with a regular external tnc you can go into converse
mode in which you can type a message and the tnc converts it to a
packet/packets. The packets can then be sent to another tnc
essentially setting up a simplex packet network. I have been playing
with APRS and have gotten the user-space soundmodem driver to work
with xastir perfectly.

I was wondering if there is anyway to use soundmodem in a type of
"converse mode" by just typing a message that is converted by
soundmodem? I have tried echoing from the command-line to /dev/
soundmodem0 but haven't been able to get it to work. I also tried
writing a small python script that would write a string to /dev/
soundmodem0, but that also did not work.

Thanks for any help.