Re: DSP stability

From: Michael Grove <>
Date: Mon, 23 Feb 1998 14:00:36 -0800 (PST)

The following is from: (
From: (Michael Grove)
Organization: Evil Dead II
Subject: Re: DSP stability
X-Mailer: NEWSie Version 0.86 (Atari)

I had to re-read this:). Sorry.

(I think the though of removing the SMT030 from my Falcon gave me the

>On Sun, 22 Feb 98 03:21 (Oliver Skelton)
> wrote:
>> Running with SCSI disconnected, displaying JPGs in a slideshow with
>> Imagecopy I find I get the occasional hang when using the DSP for
>> decompression (after letting the show run a while). This is only
>> happening with NEM_LO, and not with Nemesis off or NEMHI_AB. It
>> doesn't happen when the cpu is used for decompression.

>My Falcon tends to lock up after about 10 mins of running with NEM_LO
>but is fine with NEMAB_HI of with Nemesis off. So I think that my
>CPU isn't happy running at 40MHz. The DSP is boosted to the NEM_HI
>speeds with NEMAB_HI isn't it? This makes me suspect my CPU. I
>would like to change it with one that is definitely happy at 40MHz

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?

Received on ma. feb. 23 1998 - 23:38:00 CET

This archive was generated by hypermail 2.3.0 : ti. nov. 03 2015 - 20:07:53 CET