Userspace Soundmodem driver PTT problem solution Linux
 

Hi All

This is more a broadcast to get this data into search engines for those
that may need a solution in future.

A few years ago I started using Tom Sailor's soundmodem driver for
packet on my Linux box. At the time I found that using the serial port
didnt work so I stuck to using parallel for a while. If I used serial
the PTT would stick on as soon as either soundmodemconfig or the dameon
started.

Recently I decided to have another look. Mainly I thought it would be
resolved by a later version (now 0.9). I wasnt so lucky, so I did
another wander through newsgroups and found a posting (in I presume
German) that had the right keywords plus the command "setserial
/dev/ttyS0 uart none".

Since this command disables the port I ran it plus the command
"setserial /dev/ttyS0 uart 16550A". The PTT problem has now gone away.

Dont ask me why! I assume that my OS does something strange to the
serial port that setserial returns to a default.

Its probably not relevent but the Linux I was using was SuSE 8.1 and 9.1
professional. I only tried the setserial command on the 9.1 box.

I hope this helps someone. If you wish to email direct on this please
subsitute bcnuup for bcnntp. The address probably wont exist past late
2005.

Cheers Bob VK2YQA