Re: Snooping on the A/B

From: M Grove <mgrove_at_iwvisp.com>
Date: Wed, 24 Mar 1999 12:29:23 -0700

Rodolphe Pineau wrote:
>
> Michael Grove wrote:
> >
> > Can anyone explain how the A/B logic handles 68040 snooping?
> >
> There is no bus snooping on the AB040 because of the MACH interface
> between the AB and the MotherBoard of the Falcon.
>
> Rodolphe.

Hi Rodolphe,

That is what I thought that Doug had said a few years ago. However the
MI pin is utilized by the Afterburner in some fashion. On the 040, the
MI pin is used while it snoops the bus. I monitored the activity of this
pin with the Afterburner running (and 68040 installed). I also tried to
tied the pin HI (recommended by motorola for use with the 060) and the
A/B then fails to work with the 68040. So, the A/B may not use the
snooping function of the 040, but will not work if it is disabled. It is
using it for something, and that is what I need to find out. Somewhere
there is a problem interfacing with the COMBEL, or the COMBEL is not
getting the information it needs. Do you have more details on what the
MACH chips do for interfacing the 040 to the 030. Somewhere there is
something small that is causing the problems.

Regards,

Mike
Received on to. mars 25 1999 - 19:51:14 CET