Re: Yet another Transwarp GS upgrade question

["Bryan Parkoff" <spam>]

    You have 32K Cache Board from ///SSH Systeme that it can work with TWGS
using 16MHz.  Did it run smoothly with no error screen message?
    I only have 32K Cache Board that is designed by AE originally.

Bryan Parkoff

"Mark Cummings" <NOTfigjams@primus.com.au> wrote in message
3ee8718b_1@news.iprimus.com.au">news:3ee8718b_1@news.iprimus.com.au...
> "Tim Haynes" <timhaynes@alumni.NO.SPAM.PLEASE.uwaterloo.ca> wrote in
message
> news:bjvFa.49267$3Sm.47037@news01.bloor.is.net.cable.rogers.com...
> > My TWGS has always been a bit flakey - one of the previous owners
appears
> to
> > have been at work getting its speed up, and I'm not sure if the current
> > configuration is solid or not:
> >
> > Crystal:  28MHZ
> > Gals:  1A, 2B, 3D, 4B, 5A, 6A, 7A, 8B
> > Processor:  W65C816PL
> > Eprom:  TWGS 1.8s
> > Cache:  32K (I'm assuming it's 32K - that's what is reported in the
> control
> > panel... I have 3 chips on it that are 35ns:  Japan 9116 / HM62832HLP-35
/
> > 00016990)
> >
> > It seems to flake out on heavy disk activity... but also dies somewhat
> > randomly at other times.  I'm guessing the crystal is a bit nonstandard.
> > Can anybody tell me for sure?  Perhaps the GALs aren't right...?
>
> hi Tim,
>
> the XTAL should be a square shiny package with 4 pins, called a 1/2 size
> clock oscillator IIRC.
> the XTAL gets divided down by 4, so you actually have a 7MHz TWGS, which
is
> pretty stock standard speed. I think they came out as 6MHz originally then
> later 7MHz. (mine was a 7MHz version originally). if the CPU has
> a -6, -7, -8, or -14 ?, it means 6, 7, 8 or 14MHz respectively. no '-'
> indicates a 6MHz CPU, which probably won't run at 7MHz. If the XTAL seems
a
> bit loose, as mine did you can try bending the legs in a slight curve,
which
> will help them make better contact and hold it in better.
>
> the RAM sounds like it has been upgraded to 32K if that is what has been
> reported in the Control Panel, but it should be -10, -15 or -20 ns if you
> have a faster CPU, not -35ns which sounds a bit slow, but is probably OK
for
> a 7MHz CPU. I think the stock RAM on a 7MHz model was about that, my old
8K
> SRAMs were 7164s, but no speed data is printed on them, I'd have to look
it
> up in a data book.
> 32K cache chips will be marked 61256-15 or similar, and these days are
> normally 300mil width (0.3"). I'm sure there are lots of compatable chips
> with widely varying part numbers, only a data book will tell.
>
> if your original AE cache board has been modified, it may have 300mil or
> 600mil chips. 300mil chips have to have the legs bent out beyond 45deg to
> fit the board. 600mil chips will fit in the old sockets, but are pretty
rare
> to find. I'd have to check the part number of your chips in a data book,
> because they sound different to the ones I have.
>
> I have the SSH System 32K cache board on mine, but I also have a modified
> original cache board which I made after reading Tony Diaz's TWGS
> modification info at www.apple2.org
> the SSH board is more reliable in mine, but I think my TWGS is also
flakey,
> because it crashes occasionally at 10MHz or 12.5 MHz with either board. At
> 16MHz it doesn't get past the splash screen.
>
> my GALS are 1A, 2B, 3C, 4A, 5A, 6A, 7A, & 8A. after reading Tonys info,
you
> should be able to use any GAL versions, just that they were designed to
slow
> down the CPU a bit under certain conditions to avoid problems with faster
> XTALS. I guess that means that the Rev A GALS are best if you want
absolute
> maximum speed. The only place I you may be able to get alternate GALs
would
> be through Joachim Lange at SHH///Systems (at a price), but I'd say the
> flakeyness could be caused by other things. If you can, try swapping the
> cache chips first.
>
> Mark
>
>