Re: Need to test serial port connection

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On Thu, Feb 26, 2009 at 04:55:16PM +0000, Anne Wilson wrote:
> On Thursday 26 February 2009 13:37, William L. Maltby wrote:
> > > > Look in your /var/log/messages file. At boot, you should see the device
> > > > recognized.
> > >
> > > Feb 26 12:12:25 borg2 kernel: serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is
> > > a 16550A
> > > Feb 26 12:12:25 borg2 kernel: serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is
> > > a 16550A
> >
> > Didn't you say there was only one port? There might be a second on the
> > main board that is accessible via a header. If it's not hooked up
> > disable all but the first in the BIOS (later). It's not really hurting
> > anything as is, but it will free the I/O address and IRQ for assignment
> > to other devices. 
> 
> I believe you are right. I remember those - and the 25-9-pin adapter :-).  
> Peering around the back in a dark corner, I  could well have been mistaken.  
> OK - female socket, so that's a  COM port, I think.

Let me just throw out one caveat here: Many UPSes that use a serial
port don't really utilize it to transfer serial data, but rather just
raise/lower some of the signal lines to let the software on the host
know something has changed. Of course, lots of them, especially newer/smarter ones
DO pass serial data. But if this one is one of the dumb ones, the cable may
not even be a normal rs-232 cable, so trying to monitor it with a terminal may not
produce much useful information.

> 
> Anne
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---- Fred Smith -- fredex@xxxxxxxxxxxxxxxxxxxxxx -----------------------------
                      The eyes of the Lord are everywhere, 
                    keeping watch on the wicked and the good.
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