Re: CV Tech Piggy-Back RAM

[kmitchel@nyx10.cs.du.edu (Kirk Mitchell)]

Douglas E. Mitton (dmitton@mulberry.com) wrote:
: Hi Again Kirk ...
: 

Hi Doug!

: There may also be a fix required on the CV Tech board ...
: 
: CV.TECH on GEnie described the fix to me some time ago (Oct. 93) so
: that I wouldn't have to return the card via international mail.
: Apparently in an attempt to lower the power consumption they used a
: driver chip which wouldn't push all the 256x1 RAMs on a full blown
: card.
: 

I was bitten by this problem (though it didn't rear it's head until I 
tried to drop an Apple 1 Meg card into the slot.  I sent my card back to 
Drew about a week before he was going to ship all the CV Tech stuff to 
Sequential, and he replaced it.


: The symptoms are random, frequent and constant memory test failures
: and crashing of the GS.
: 

Mine weren't so random.  They happened every time!

: The fix involves replacing the IC chip at location U34 from a 74HCT245
: to a 74LS245 (available at Radio Shack).  The chip is soldered in BUT
: its through hole technology so "not as complicated as surface mount".
: 
: I would temper this with anyone who has replaced an IC before could
: fix this ... I installed a socket at the same time ... no real reason,
: it just made me feel better.  THAT 20 PIN CHIP SOLVED THE PROBLEM!!!
: 
: Later!!!
: 

Neat fix.  I'm sure someone out there could use this information.

: 
: >Steve Townsend (steve.townsend@rook.wa.com) wrote:
: >: Configurations!
: >:     

Ah, Steve?  Did you get my e-mail?


-- 
Kirk Mitchell B-{)    USD #209  Moscow, KS
kmitchel@pld.com <--- preferred  
K.MITCHELL4@genie.com kmitchel@nyx.net
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