Re: DSP stability

From: Richard Elwell <rjelwell_at_telemedia.co.uk>
Date: Mon, 23 Feb 1998 09:28:47 +0000

On Sun, 22 Feb 98 03:21 oskelton_at_cix.compulink.co.uk (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.

> I guess the first step is to try a heat sink on the DSP... or at
> least measure it's temperature to see if it is hot. Can someone
> remind me roughly where the DSP is on the circuit board?

I think the DSP is towards the back right corner roughly under the
back end of the floppy disk drive, if it was fitted in it's normal
place. It might have a Motorola symbol on it and will almost
certainly have 56001 written in some form.

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
sometime.

You mention having SCSI disconnected. Do you not get the problem
with SCSI connected.


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