Subject: Re: Support for 425e with SGC video?
To: Jason Thorpe <thorpej@nas.nasa.gov>
From: mike smith <miff@spam.frisbee.net.au>
List: port-hp300
Date: 04/25/1997 12:20:49
Jason Thorpe wrote:
> 
> SGC video is not currently supported.  There were at least two problems
> the last time this was discussed here:
> 
>         (1) The autoconfiguration infrastructure could not sanely
>             support another bus.
> 
>         (2) No one with the right combination of:
> 
>                 (a) hardware
>                 (b) documentation
>                 (c) time
>                 (d) clue
> 
>             existed to do the work.  :-)
> 
> (1) has been addressed, and adding a new bus type to the hp300
> autoconfiguration model is trivial (right Mike? :-)

Correct, with the notable exception of cascaded interrupt controllers,
which are a nuisance in anyone's language.
 
> ...Do you have another hp300 or other NetBSD/m68k system on which you can
> build kernels, and whatnot?  Or, some suitable cross-development environment?

Note that if you have a PC or similar that you can connect to the
serial port on the 425, you can run it just fine with a serial console
until you have the SGC stuff going.

Hang a terminal off the serial port set to 9600,n,8,1, power up, 
get one beep, wait a bit, get two quick beeps, hit 'R' and Enter
and you'll be greeted with the serial boot screen.  

If you go this way, talk to me and I'll write some more serious
words about how you go about fighting the HP-mode prom to make
it default to the serial console and look on the network for
a boot server etc.

You'll need something to bootstrap it off first time around too;
another NetBSD box is best for that.

> ...VGA support will do nothing to help the 425e folks.  And, there are
> some 425t folks who would benefit from SGC support, since you could get
> SGC for the 425t, as well (although, I don't think it was very common).

Hmm, my 425t has an SGC slot on the motherboard; I presume that one
loses the DIO-II connector and cable and replaces it with the
corresponding SGC connector/cable, but I have none of that.
 
> Jason R. Thorpe                                       thorpej@nas.nasa.gov

--
Mike Smith  *BSD hack  Unix hardware collector
The question "why are the fundamental laws of nature mathematical"
invites the trivial response "because we define as fundamental those
laws which are mathematical".  Paul Davies, _The_Mind_of_God_