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From: jb10320@uxa.cso.uiuc.edu (Desdinova)
Newsgroups: comp.sys.apple2
Subject: Re: non-DMA at 4 Megs (GS)
Message-ID: <1990Nov4.182752.15600@ux1.cso.uiuc.edu>
Date: 4 Nov 90 18:27:52 GMT
References: <9011040741.AA24846@apple.com>
Sender: news@ux1.cso.uiuc.edu (News)
Organization: University of Illinois at Urbana
Lines: 30

In article <9011040741.AA24846@apple.com> MQUINN%UTCVM@PUCC.PRINCETON.EDU writes:
>T
> .CIS.OHIO-STATE.EDU>
>
>On Sat, 3 Nov 90 12:15:58 GMT Desdinova said:
>>
>>   The limit of memory expansion is based on one and only one thing-
>>only four rows of RAM are directly supported by the IIgs and it's
>>DMA scheme.  Four rows = 1Meg with 256K chips, or 4Meg with 1Meg chips
>>(SIMMs or what not).
>
>So, I guess the answer to the question is that the 256k on board isn't DMA
>compatible?  Or is it, and only the first 3.75megs on a RAM card are DMA
>compatible?

  Oops, I blew it.  All RAM on the motherboard is DMA compatible.
RAM on a RAMcard is DMA compatible if it's designed as I said above
(only 4 rows).  With a ROM03 and a 4Meg card, you can have 5 meg of DMA
compatible memory.

>| This is your brain on frog licking.|    mquinn@pro-gsplus.cts.com  |

Eh?

--
Jawaid Bazyar               | Blondes in big black cars look better wearing
Senior/Computer Engineering | their dark sunglasses at night. (unk. wierdo)
jb10320@uxa.cso.uiuc.edu    |      The gin, the gin, glows in the Dark!
   Apple II Forever!        |                             (B O'Cult)
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