Re: ZIP GSX 1.0.1 vs 1.0.2

[Drew <GoggleDrew@gmail.com>]

On 30 Aug, 00:03, Steven Hirsch <snhir...@gmail.com> wrote:
> Drew wrote:
> >> So what the difference is between the two ZIP GSX boards, or should I say
> >> the ASICs (large square IC), really isn't know (at least to me).  Maybe they
> >> weren't sure about the ASICs ability to work and only has a small batch
> >> produced.  Being this was 1989 (?) it was in the middle of the 'custom
> >> logic'
> >> reevaluation where it was really starting to become 'cheap' to produce these
> >> large ASICs.  So if the 1.01 boards kind of worked, and worked good enough,
> >> why not sell them?  It's just a business decision at that point.  Then maybe
> >> they fixed a few minor reliability issues and produced a second batch,
> >> v1.02.  Of course I have no idea what the real story is and I'm just
> >> speculating.  In 1989-90 we all kind of knew that Apple II was on its way
> >> out.  So that's where I start to consider the 'small batch' theory.
> > Thanks Henry for that, didn't really cross my mind that the ASICs
> > might be different between the two boards. Looking at the picture on
> > your site of the ZIP GSX 1.0.2 the ASICs do indeed look different
> > types to the one on my card. I did speak to you about this before, but
> > was bugging me that my card had the sockets :-).
>
> My point is that those two chips were designed to do something with signals on
> the card and that the differences between 1.01 and 1.0.2 must amount to more
> than their presence or absence.  In order for it to work without them, there
> must be jumpers to provide the equivalent paths in the circuit topology.
>
> Perhaps they are simply buffers?
>
> So, it sounds like it's possible to upgrade a 1.0.1 rev GSX from what I'm hearing.
>
> > My cards run fine, they never hang, get the odd crash but never sure
> > if thats the card or not to be honest. I was happily playing OOTW for
> > over an hour at full screen and full 12.5Mhz speed the other night....
>
> Unfortunately, my 12.5Mhz. 1.0.2 board (I have one of each) does not run
> reliably.  If left on it will eventually put the machine in a state where the
> mouse will move the cursor, but nothing else responds (nothing from keyboard
> or mouse buttons).
>
> Maybe I'll have better luck with the 1.0.1 unit.
>
> Steve

Hi Steve,

Well on the back of my 2 x 1.0.1 boards there is a capacitor...maybe
thats the difference. Anyone confirm if there is a capacitor on the
back of the 1.0.2 board?  Good luck with the 1.0.1 card, I was able to
to get mine going what seems to be relatively reliable at 12.5Mhz (and
larger caches), both with a DIY method (i.e using adapters for cache
modules) and sent of the other one to get done properly.

Cheers
Drew