Re: ZipGSx Upgrade Problem??

["David Chiu" <none@nowhere.org>]

Make sure you check the data sheet for the part you are trying to use. The
part must be pin compatible. There apparently are several different pin outs
for 32k x 8 static RAM.

"Marvin Miller" <marvinisnot@home.com> wrote in message
news:3a1a23f8.1563461949@news...
> Hi RubyWand;
>
> The sockets are in the proper location. The card actually has some
> silkscreening to show where the sockets should be and this works with
> either .3 or .6. Also, in your faq it mentioned just cutting out
> sections and putting in sections. Extrapolating on these  two sources
> - they're in the right place.
>
> As for oscillator, it's the stock one for 7 MHz proc speed. I didn't
> want to change anything else at the start, and the card does work, but
> only with the DIP set for 32k cache. I checked the soldering on the
> back of the second bank of chips (obviously first bank works as it
> runs at the original 32k) and they all look 100% As I mentioned, the
> job went great and I was very confident of the work (I have zip for
> soldering skills but it looks good :-)
>
> Is it right to have 4 of the same SRAM's, or did I need to buy two of
> one type and two of another? All I did was get 4 identical SRAM's with
> two being a slower rating. Correct?
>
> Also, is the order correct? This is from left to right as viewed head
> on
> ;
> TAG 15ns DATA 20ns TAG 15ns DATA 20ns
>
> If that's all correct, I'd have to say I have either;
>
> - A bad chip
> - Bad soldering
>
> Hmmmm......
>
> Best Wishes;
> Marvin Miller
>
>
>
> On Mon, 20 Nov 2000 23:45:15 -0600, Rubywand <rubywand@swbell.net>
> wrote:
>
> >Marvin Miller writes ...
> >>
> >> Hi;
> >>
> >> I have a ZipGsx that I just did an upgrade on. Specifially, I soldered
> >> in (4) .300 sockets and installed new cache memory chips. All went
> >> really well with the work, it took a while (about 4 hours) but came
> >> out looking more/less like no one had been there!! I was, and am, very
> >> pleased with the work.
> >>
> >> I bought 4 new chips for the card and I'm wondering if this is where
> >> the problem lies. Here's the deal;
> >>
> >> I bought (2) 32kX8 SRAM's at 15ns AND
> >> I bought (2) 32kX8 SRAM's at 20ns
> >>
> >> On the card there are 4 sockets labelled;
> >>
> >> TAG, DATA than TAG, DATA
> >>
> >> Understanding that the TAG should be faster than the data, I put the
> >> chips in like this;
> >>
> >> 15ns 20ns 15ns 20ns
> >>
> >> I than went in and changed the  7&8 DIP switches to OFF as per the
> >> FAQ. I plugged it in and it didn't work! I got worried a little, but
> >> realizing that everything had went so well with the soldering - I
> >> changed the 7&8 dips back to were they were and re-tried. Presto!
> >> All works well as long as the Zip's Dip's are set to 32k. This Zip
> >> originally had 32K but should now have 64K.
> >>
> >> So, I'm wondering if I have the chips in the wrong order or something
> >> like that? The memory I bought were just standard 32kX8 SRAM's with
> >> two being a little slower than the rest.
> >>
> > ....
> >
> >     What oscillator frequency are you using?
> >
> >     Check your 300 mil RAM placement. Unless your board's RAM layout is
different
> >from ours, each skinny RAM should be plugged in to the left and center
columns. The
> >center and right columns are the same-- i.e. RAMs plugged into these two
columns
> >would not do anything.
> >
> >     If the RAM chips are placed correctly and the board still does not
work in
> >"64k" mode, you could try swapping in a slower oscillator module.
> >
> >
> >
> >Rubywand
>