Subject: MI Z8530 driver on the Alpha can't cope with nutty serial port
To: None <tech-kern@NetBSD.ORG>
From: Ken Hornstein <>
List: tech-kern
Date: 05/16/1997 16:43:21
As a few people know, I've been working on getting the MI Z8530 driver
working on the Alpha (with the eventual aim of adding keyboard/mouse
support a la the sun3 port so the TurboChannel Alphas can have
framebuffer console support, and maybe even down the road a working
X server :-) ).

Well, I got it working ... but I have a small problem.

The Z8530 serial ports on the Alpha (and the pmax, I believe) are wired
in a strange way.  Specifially, channel A DTR and RTS lines are wired
into the channel B serial port, and the rest of the channel B lines
are brought out into the external serial port.  The remaining channel A
lines are used for either the keyboard or the mouse.

The MI Z8530 code assumes (reasonably enough, I suppose :-) ) that the
DCD and and RTS lines for the "right" channel correspond with the
correct serial ports.  However, this doesn't work on the Alpha.

So, I'm wondering .... what is the "right" thing to do at this point?
Would the author(s) of the MI Z8530 code be willing to work with me on
a solution?  I'm willing to write the code, but I'd like to make
changes that are acceptable for the CVS tree.