Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!jarthur!nntp-server.caltech.edu!toddpw
From: toddpw@nntp-server.caltech.edu (Todd P. Whitesel)
Newsgroups: comp.sys.apple2
Subject: Re: DMA Compatability
Message-ID: <1991Apr24.002044.25147@nntp-server.caltech.edu>
Date: 24 Apr 91 00:20:44 GMT
References: <11079@mentor.cc.purdue.edu>
Distribution: usa
Organization: California Institute of Technology, Pasadena
Lines: 20

grochoci@mentor.cc.purdue.edu (Paul Grochocinski) writes:

>	What I have is a fully populated Apple Memory expansion card for my GS.
>The one that came with it.  Is any of the memory on this board used as DMA?  If

Apple's board can always be used with DMA peripherals.

>not, can I get it to be or am I stuck with it(with the exception of getting a
>new board)?  If so, how do I use it?  I have tried copying Battle Chess to the
>RAM and boot it from there but I don't notice any real difference in the timing

DMA only works for moving stuff into and out of the computer. Copying something
to the RAMdisk may use DMA for the copy, but once the files are on the RAMdisk
then the CPU has to shuffle things in memory itself.

You do not have to worry about DMA unless you have a DMA peripheral like the
Apple High Speed SCSI card, the RAMfast, or the Visionary.

Todd Whitesel
toddpw @ tybalt.caltech.edu