Re: AP-67 82C37 Application Note

On May 24, 6:15 pm, "Wolfgang Kern" <spamt...@xxxxxxxxxx> wrote:
Hans "HT-Lab" asked:

Hi all,
Does anybody have, or know were I can find a copy of the AP-67
application note . I googled for a few hours but failed to find it.
This appsnote describes how to interface an 82C37 DMA controller to
an 8086.

IIRC I once saw it in the appendix of one of the Intel books (~1979).
This books will not be available anymore, but Intel may have 'AN-67'
(they called it "AN-.." rather than 'AP') in their archive.


Thanks, I will try to find the 1979 Intel databook (anybody has a
copy?).

I am particular interested in how to add a page register for
the memory-to-memory transfer option,

I'd add one (three for 32 bit) HC374 or similar to it.

What I am after is how to select the latches. During normal IO-2-
memory transfer I can use the DACK signals as latch enables, however,
for memory-2-memory DACK0/1 are not asserted. The only indication that
a memory-2-memory transfer is in progress is that AEN is asserted but
none of the DACK signals. I can use this to select 1 latch/page
register but I need one for both the source and destination.

I suspect that you can only transfer a blocks of memory within a
single 64KByte/128KWord page.

Thanks
Hans
www.ht-lab.com

__
wolfgang

.