XFRB buffer

From: Magnus Kollberg <Magnus.Kollberg_at_emw.ericsson.se>
Date: Fri, 30 Jan 1998 09:03:29 +0100

Hi,

Well there have been some discusions on the newsnet regarding
_FRB and XFRB buffer and AB040s and MaigC problems.

It looks like the root to the problem is that Andreas hasn't
understod that the Falcon treats Fast-RAM different from the
TT. On the TT you can do DMA transfers to/from Fast-RAM
which you can't do on a Falcon with Fast-RAM. The TT
doesn't either have a 040.

Also, Uwe explained what the XFRB buffer was for and that was
probably causing the problems Oliver had with GEMAR as I don't
think the 68040TK (version 5.07) does something about. It should
be treated as the _FRB buffer and marked as none cacheable
but currenty it's ignored. Correct me if I'm wrong.

So I was going to ask Doug if it would be possible to
mark the XFRB buffer as none cacheable as well? I
think it would be important update as I would suspect
that most backup programs uses the XFRB buffer and maybe
also CD-ROM writers.

Doug?

For MagiC we just have to wait until Andreas comes to his sences
and sets up a correct _FRB cookie.

//Magnus Kollberg


 
Received on fr. jan. 30 1998 - 17:46:00 CET