On Wed, 14 Apr 1999, Douglas R. Troeger wrote:

> I nonetheless tried various modem initialization
> strings, both with crtscts and nocrtscts, on the
> PB.  The ATZ string just locks the port
> (ps -aux  shows the process, which does not
> respond to kill -9); other strings
> (AT&D0, AT&F, AT&F&C1&D0&Q5)
> yield a message back from chat
> 
> chat[pid] Can't get terminal parameters:
>  Operation not supported by device.

It's not the init string--it's the fact that chat can't write to the
port, so it's probably blocking on ttyout, as viewed with `ps -l'.

You might be able to figure out exactly which ioctl fails, by
attempting to set up the port with "stty", after opening "cu", but
before typing a character. e.g.

In one window, run

	cu -l /dev/tty00

Then in another,

	stty -af /dev/tty00
	stty -f /dev/tty00 clocal
	stty -f /dev/tty00 -crtscts
	stty -f /dev/tty00 -ixoff
	stty -af /dev/tty00

Note that the `-' turns something off, the argument without a `-'
turns it on. If all that succeeds, you should then be able to type AT
commands in the "cu" window, and see the responses. Exit "cu" via
[CR], tilde `~', (wait), then period `.'. If it fails, maybe "stty"
will at least give you a more descriptive error message.