Re: Alltech Focus Hard Card/8 MB Sirius RAM

["Barry Rees" <Barry.Rees@prodigy.net>]

> "Barry Rees" <Barry.Rees@prodigy.net> wrote,

(snip)
> >One thing that came up was a mention that in one particular situation
AppleWorks wouldn't work with a 8MB Sirius and the only way this person
could get it to work was to create a 4 MB RAM disk and run it that way. 
(snip)


pubpc1@library.ucla.edu wrote in article
<5jqkub$nrc@uni.library.ucla.edu>...

> Yes, I know of that situation.  It happens when you are using the Sirius
> (or, apparently, any other 8MB memory expansion) with the Apple II High
> Speed SCSI card with DMA turned on.  When the Apple card tries to DMA
> to the memory space above the first 4MB on a ROM 1 or the above the
> first 5MB on a ROM 3, the access is likely going to fail.  I don't know
> about the RamFAST, which has hardware to get around this problem, but
> I suspect that in order to be 100% safe, you'd want to disable DMA as
> well.  This problem is not limited to AppleWorks, btw.  One way to use
> the DMA cards with DMA turned on in an 8MB GS is to set up a 4MB RAM
> disk (3MB on a ROM 3), which solves the problem because the computer
> will now only DMA to 4MB or 5MB.  Now of course if your intention is
> to expand usable memory space for programs, this "solution" is
> counterproductive.
> 
> The good thing is that if you are going to use the Sirius with a Focus,
> this problem does not show up at all.  The Focus is an Enhanced IDE
> controller that does not use DMA.  Therefore, it has no conflict with
> 8MB.  The amazing thing is that the little drive is probably the fastest
> non-DMA drive you can get - it is certainly faster than an Apple High
> Speed SCSI card with DMA turned off.
> 
> -Scott G.
> 

Scott,

The full 8 MB expansion without any conflict is what I'm looking for.
Thanks again for the input. Greatly appreciated.

Barry