Re: AAUGH! Vulcan 20 dying??

[dalloff@gcfn.org (Dave Althoff Jr)]

Mark Cummings (NOTfigjams@primus.com.au) wrote:
: >Unfortunetly the EPROM on the card is coded to that particular make, model
: >and size of drive. It's unfortunate that AE did that as it now keeps
: everyone
: >from upgrading their drive. Other than finding another duplicate drive. the
: >only options are to go SCSI or get an ide card from ///SHH Systeme in
: >Germany.

: or... figure out the EPROM code as I hope to do to my now dead VulcanGS40Mb
: WD93048-AD.

: ///SHH Systeme offered me a replacement 160Mb Conner drive for mine, but at
: a price not worth doing IMO. The IDE card options are also pricey, but
: probably a much better idea as you would have a larger choice of drives. I
: think the maximum drive size is 250Mb with their cards, but this should be
: quite useful on a IIe or IIGS.

Actually, the best solution might be to buy a new Focus for the IIgs at
work (which I noticed today is nearly full!) and repurpose that 20Mb Focus for
use in the ][e.  It seems a shame, since I jumped through a few hoops to
mount the drive in that ][e case and adapt the (upgraded) power supply. 
(The original Vulcan case now houses a SCSI drive in my IIgs).

: one possible explanation on the bit only appearing on every second character
: (byte) is that the Vulcan uses 16 bit I/O between the card and HDD and 8 bit
: to the Apple bus. I would suspect a single stuck bit on the card.

Except that first of all, it doesn't happen on every second byte...but
that might be explained if there is a nibbleizing process as there is for
floppies.  'Course I haven't looked closely enough...maybe you're right
and it's setting a bit on every other character but I am not noticing it
because (duh!) some characters already have that bit set.  Ewwww...no way
to automate THAT fix!

And second, it's not consistent across the files.  I'm talking about a
single block or two in the middle of a file.

I did think of another possibility.  The first sign of trouble was when I
was running the files into AppleWriter to do some editing.  Certain files,
when I accessed them, would cause all of my drive access to go flaky in
just this manner.  What these files all had in common was their logical
position on the disk:  they were all located in the directory...

/RAVEN/COASTER/REPORTS/R1999/PNW.99/

...and the affected files had names like "SILVERWOOD.TXT".  Meanwhile, a
file such as "OAKS.TXT" was seemingly unaffected.

This suggested to me that perhaps I was creating trouble by overrunning
the ProDOS pathname buffer or something.

Hmmm.......

Well, I'll keep the group updated as I progress with this thing...! 
Someone slipped me an old IDE drive recently, I thought I might test
another theory just for grins....

--Dave Althoff, ][.



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