> 
> Waldi Ravens <waldi@moacs.indiv.nl.net> in atarix:
> 
> > leo@ahwau.ahold.nl (Leo Weppelman) in atarix:
> > 
> > > I got a hold of minicom (and was able to successfully compile it) and 
> > > tried to dial out using Modem 2 /dev/mdm02.  I get a message saying 
> > > "..unable to open /dev/mdm02".  And when I plug the modem to Serial 2, 
> > > the RD, SD, TR, CS light up simultaneously and I get the same message.  
> > > With modem 2, only the CS is lit until I goto minicom, then the TR lights 
> > > up.  But still, I get that "unable to open device" message.
> >
> > As far as I know, you'll need a null-modem cable to hook-up a modem to
> > serial2.
> 
> ?? Except for the unused RI signal, everything (CD, DTR, DSR, RD, TD
> RTS, CTS) seems to be available at the serial 2 port?
I always though serial2 was wired for a terminal while modem2 was wired for
a modem, looking at the scematic, I'm beginning to doubt it :-)
Anyway, to the original question: when no one has the port open, _all_
lights should be off (exept for DSR, which comes from the modem itself).
When the port is opened (should happen with O_NDELAY), DSR&RTS should
be lit. Before writing to the port, it should be put in CLOCAL as
there (probably) will be no carrier...
>  
> > Are you sure that minicom is _allowed_ to open the mdm02 port?
> > Normally the port is owned by uucp.
> 
> If this would be the cause of the error message, I would expect the
> open() call to fail. As I understand it open() does succeed, otherwise
> DTR wouldn't light up. AFAIK "unable to open..." is not a strerror()
> message, so it doesn't necessarily indicate that open() fails. It
> could be a failing ioctl() or whatever.
They might be setting it with: wait-for-output to drain and timeout...

This being crossposted is quite confusing :-), I'll once again cross-post
but propose this discussion being continued on port-atari?

Leo.