Coder's Guild Mailing List

Re: Question on DMA use

Posted by Osipov Alexey on 2000-01-11

Thank you for replaying my question Jes.

> Are you sure your system supports memory to memory transfers. I seem to > remeber having read some HP Vectra manual, which stated that i/o to i/o > and memory to memory transfers were not supported on that system. And I > think that HP usually keeps to the standard, so I am afraid, but not    > sure, that your system also does not support memory to memory transfers.

But in my sources memory to memory transfer using DMA(Intel 8237A or
somting like that) is possible it takes two channels 0(read) and
1(write).
Using port 8H (comand register) first bit (less significant) enables
emory to memory transfer. It also supports constant address for channel
0 to fill memory by the same byte.

So if some one knows how to start transfer(I know where to send DREQ bit
for channel but may be I have to confirm request in manual it is named
DACK)?

Bye.
Sponsored by Wrox Press - www.wrox.com. Programmer to Programmer (TM)
To signoff send a mail to listserver@xxxx.xx.xx with 
  "signoff tcg" in the body of your message.