Re: MAJOR HD help needed!!!

[jamesb@ecst.csuchico.edu (James L. Brookes)]

In article <1993Sep1.134052.23517@actrix.gen.nz>, David Empson
<dempson@swell.actrix.gen.nz> wrote:
>In article <i108642@pro-ict.cts.com> shack@pro-ict.cts.com
(Randy Shackelford) writes:
>> "Seth D. Kadesh" <thes+@CMU.EDU> writes:
>> 
>> >> Hardware: Apple II HS SCSI, ROM1 (0 upgrade), Octoram w/ 4 Megs, 1 3.5"
[...]
>> I'm not sure it can cause I/O errors but one thing to keep in mind is that
>> you're using an old non-DMA-compatible memory card with a HS SCSI. I'd try
>> turning off DMA and see what happens.
>
>The OctoRAM is DMA compatible, provided you only install 4 megabytes
>(or 1 megabyte if you're using 256k SIMMs).

Well, _some_ OctoRAMs are DMA compatible.  Others, like mine, seem not
to be (I have 4mb in 1mb SIMMs installed, btw).

>A card which is not DMA compatible will suffer memory corruption (and
>probably random crashing) rather than causing an "I/O error".

Yeah.  When I upgraded from 2mb in 256k SIMMs to 4mb of 1mb SIMMs I tried
activating DMA.  I tried booting twice; on each occation it didn't even
make it to Finder without trashing parts of my HD first.  The second time
it never even made it to Finder.

>David Empson                                                               
>dempson@swell.actrix.gen.nz                                                
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|          James Brookes            | Inet: bb252@cleveland.freenet.edu |
|``What, me worry?'' - A. E. Neuman |   jamesb@cscihp.ecst.csuchico.edu |
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