Re: TurboRez - Released Yet?

[stc7@cunixb.cc.columbia.edu (Steven T Chiang)]

In article <1993Mar27.083623.852@ee.rochester.edu> seah@ee.rochester.edu (David Seah) writes:
>
>In a previous chat on AOL, Bill mentioned that he bypassed the 1MHz
>bottleneck.  I/O and DMA to a peripheral card are limited to 1MHz by the
>IIGS, but there is nothing that stops a peripheral card from "snooping" the
>system bus to essentially read data at 2.8MHz.  Apparently, there is a
>special sequence of instructions that is executed that activates the
>TurboRez, which then reads data from the multiplexed data lines as put there
>by another special sequence of instructions.  Hence, there is no mucking
>about with DMA or the $E0/C0xx range.

	I remember this...  however, DMA is still faster than mvn's..
(I did a test a while back)  If there's a graphics coprocessor, I
don't know what the limitations would be...   If the graphics
coprocessor could work at the full 2.8 that would be cool, but I don't
know if it can...

>Dave Seah (seah@ee.rochester.edu, AFCDaveS@aol.com)

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