Subject: Re: serial 56k?
To: Hauke Fath <hauke@Espresso.Rhein-Neckar.DE>
From: Bill Studenmund <wrstuden@nas.nasa.gov>
List: port-sparc
Date: 11/13/1999 10:12:21
On Sat, 13 Nov 1999, Hauke Fath wrote:

> At 22:53 Uhr +0100 12.11.1999, Bill Studenmund wrote:
> >On Thu, 11 Nov 1999 svinto@ita.chalmers.se wrote:
> >> the print-server i'm using today is an old Macintosh SE/30 also
> >> running NetBSD 1.4.1 which works like a charm, only it's a bit slow.
> >> if i'm not mistaken both these machines use the same serial chips. so
> >> why can the Mac do 56k but not the Sparc? or am i missing something
> >> here?
> >
> >While the two machines use the same serial chip, they DON'T use the same
> >clock frequency to drive the baud rate generator. The Sun machines
> >actually use a slightly higer clock rate. The net result is that the
> >highest two baud rates the mac can support are 57600 and 38400, which for
> >suns they are 76800 and 51200.
> 
> Make that 115200 and (theoretically) 230400 for mac68k after Scott's recent
> changes. These two may be of pretty restricted value, but see PR#8070.

Very true. I was limiting myself to what the BRG can do, since the sparc
driver only uses it. :-)

Take care,

Bill