Subject: Re: Is "/dev/ttya" "COM 0" ?
To: Ben Cottrell <tamino@wolfhut.org>
From: Brett Lymn <blymn@baesystems.com.au>
List: port-sparc
Date: 09/15/2003 12:22:59
On Sun, Sep 14, 2003 at 06:22:16PM -0700, Ben Cottrell wrote:
> 
> You should be able to. Although, if your sparc is one of the ones
> with the multiplexed DB25 for both serial A and B, and if you don't
> have the right kind of adapter, then you'll only be able to use
> /dev/ttya (it's the one that comes through the standard pins in
> the DB25, whereas /dev/ttyb would be the one you have to have the
> adapter to be able to use)
> 

Just to be pedantic :)

The ttyb pins are _also_ rs232 standard.  They are the "secondary"
port pins and are actually included in the standard for the pinning of
a db-25 connector.  The major difference between a and b is that some
of the control signals are not available on port b so you probably
don't want to connect your UPS to that (though that depends on the
sort of interface on the UPS).  You can quite happily run the console
on ttyb, I do that with a machine at work because I needed ttya to
talk to a modem.

-- 
Brett Lymn