Date   : Mon, 04 Nov 1985 16:36:49 GMT
From   : pete%stc.uucp@BRL.ARPA
Subject: The DMA Address

This is a brief summary of responses I received to my original
posting of ~3 weeks ago, regarding where I could find the location of
the DMA address on a CP/M-80 system.

The answer, as I could have found out myself if I'd looked a little
deeper, is in the BIOS. It seems to be a simple matter, if you have
the source, to add a GETDMA call to the BIOS jump table or to
intercept SETDMA calls to the BDOS if you don't.

Thanks in particular to Keith Petersen for his extensive help.
Also to Rick Conn for pointing out (to my unsuspecting horror)
the nonreentrant nature of the vanilla BDOS and to Bomberger (of
Poor Person Software) for his unselfish assistance.
And, of course, to all the others who mailed me.

The real-time clock hardware goes in this week (D.V.).

The ratio of e-mailed responses to postings was exemplary. This seems
to be one newsgroup that knows how to do it right.
-- 
       Peter Kendell <pete@stc.UUCP>

       ...mcvax!ukc!stc!pete

       `Turn up the Eagles, the neighbours are listening'