Subject: Re: HP 385 and 425e
To: Michael Wolfson <mw34@cornell.edu>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: port-hp300
Date: 07/31/1999 12:01:20
On Sat, 31 Jul 1999 13:36:14 -0400 
 Michael Wolfson <mw34@cornell.edu> wrote:

 > I've heard of the obscure 382, but what's a 385?

385 is apparently a 33MHz 68040 ... I don't actually have one, but I think
Todd Miller does.

Anyhow, I suspect it's 380-like, but it has a different MMU ID.  In fact,
I suspect that a 380 is converted to a 385 by moving the "CPU speed" jumper
on the mainboard from "25" to "33" (this is how you convert a 425 to a 433;
the jumper changes memory wait states, I believe, and also changes the
MMU ID).  The 385 probably worked fine before, actually, but printed
the wrong CPU speed.

 > Out of curiosity, what do you mean by 'add support'?  I thought the 425e
 > already booted, aside from using SGC for console.

It probably booted, but the console (even the serial console) wouldn't
work because it was misidentified as a 380 (and thus the APCI code would
bail early, since it machineid wasn't one of the 400-series IDs).

 > Nevertheless, it's cool that y'all are still adding more support for hp300!

It's actually a pretty easy to maintain, since there's not a lot of "new"
hardware out there :-)  (Tho, there is a lot of major development work to
be done, to modernize the port.)

        -- Jason R. Thorpe <thorpej@nas.nasa.gov>