Re: TurboRez - Released Yet?

[bazyar@teal.csn.org (Jawaid Bazyar)]

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.

  That's kinda wierd because there's nothing that prevents DMA at 2.8MHz,
at least according to the Hardware Reference.

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