Re: DSP stability

From: Richard Elwell <rjelwell_at_telemedia.co.uk>
Date: Tue, 24 Feb 1998 09:38:47 +0000

On Mon, 23 Feb 1998 14:00:36 -0800 (PST) Michael Grove wrote:

> grovem_at_ridgecrest.ca.us (Michael Grove) Organization: Evil Dead II
> I had to re-read this:). Sorry.

It's quite alright. I had to re-read the initial post a few times
before I saw the NEMAB_HI reference.


> Your right about the DSP and NEMAB_HI setting. Have you ever looked
> at the model of your 040? I finally lifted the heatsink off to find
> it was 33Mhz rated. I have a 40Mhz CPU, but mine is soldered to the
> A/B requiring a little more work than I would like to do on this
> elusive piece of hardware:). I can install a 43.9Mhz clock in the
> Nemesis, and it will run without crashing, but the DMA goes to hell.
> Any higher clock and the machine just locks upon switching. Did you
> shield and ground the A/B and Nemesis as Doug recommended?

My 040 is a 32 or 33MHz one, socketed. I know I unplugged the LC040 I
had at first and replaced it with an RC040, when Dave at Titan Designs
was generous enough to let me swap the chip with one from a newer AB
he had. Doug actually fitted my Nemesis so it is probably done to his
immaculate standard. Though because of the broken 030 pin he was
probably just relieved to get it running at all.

I hate to admit this but I think the accidental running of NEM_HI on
a couple of occasions may have damaged the chip so it dies after a few
minutes running of NEM_LO.

Most of the time I leave Nemesis off but regularly I switch to
NEMAB_HI to allow me to use the 640x480 hi-colour mode.


Rich.
Received on ti. feb. 24 1998 - 17:23:00 CET