Are the tty ports jumpered for RS232 or RS485 signaling levels?
I believe the default is RS485. Your modem is RS232.

> I was wondering if anyone can give me a hand with my modem problems.
> 
> I have set the modem up on serial port B of a Sparc 1+ running a generic
> 1.4.1 kernel, and so far have no been able to get it to play ball at all.
> (Modem is a US Robotics Sportster Flash flashed to v.90) I saw the earlier 
> postings to this list and followed the advice, and whilst I am further on, 
> have still a bit to go. 
> 
> The latest state of things is that trying to use cu -p modem to test 
> the line reports that the line is busy if you try to use /dev/ttyb and
> will connect, but will accept no commands bar ~. and return no output
> whatsoever if /dev/dtyb is set.
> 
> Needless to say the getty entry for /dev/ttyb in /etc/ttys has been
> removed and set to off, and the speed is set to 38400 (though even trying
> at 9600 has no effect).
> 
> I cant see what else immediately springs to mind, I have had the cable 
> and modem on a pc to test them and they appear to be fine.
> 
> Is it possible that the serial ports themselves are dead ?
> 
> Any help greatly appreciated.
> 
> Steve.
> 
> --


Michael Thompson
E-Mail: M_Thompson@IDS.net