Subject: Re: High serial port (output) speeds
To: None <>
From: Michael Ritzert <>
List: port-sparc
Date: 10/22/1999 10:25:08
Jukka Marin writes:
 > On Thu, Oct 21, 1999 at 11:20:26PM -0400, der Mouse wrote:
 > > I think I know why the zs chips are normally run with a X16 clock
 > > divisor.  But is there any reason why they shouldn't run X1 if userland
 > > requests a baudrate that can be achieved that way but not with X16?

 > In a quiet environment with good cables and UARTs and transceivers it
 > shouldn't really matter - but if there's noise and/or voltage spikes,
 > you'll get transmission errors easier with the 1x sampling method
 > (although I have used it successfully when creating bit-banged serial
 > ports).

So, is it possible to include it as an option, e.g. only enable the
patch for speeds above 38400 baud?

BTW, is it possible to run the zs at 57600 or 2x57600 baud in order to 
support common modems (multiples of 38400 are not sufficient).
Getting 57600 baud with a reasonably low error rate would already be a 
big win in connection with modems or external ISDN adaptors.

 >   -jm