Re: I am working on a GS accelerator, can you help?

[supertimer@aol.com (Supertimer)]

chessie@ospnet.nshore.org (Adam Barr) wrote:

>I have a person who is pretty good at electronics, he is making some 
>custom digital cameras for me right now. He seems to think that he can 
>make an accelerator for a GS. I told him I would send him a GS and 
>whatever info I can get. I know I do not have the knowledge to share with 
>him, but I was wondering if any one could email me information on who the 
>two current GS accelerators work so I could give it too him. I will let 
>the A2 community know how it progresses, but I need some info to get him 
>started. I think I should probably get him info on the GS itself, and 
>maybe even a motherboard schematic. So if anyone can share this 
>information or what ever else you think I need please email me. Thanks!

Hi, what information do you need?  From what I understand,
the two IIGS accelerators are both caching accelerators
having anywhere from 8k to 128k of static RAM for a cache.
At the heart of the accelerator is Western Design Center's
(not to be confused with Western Digital, the hard drive
maker) 65C816 rated at 14Mhz (but apparently able to
function fine at 20Mhz, as seen in Commodore accelerators).

The logic on the card allows the CPU to run at a full, say,
15Mhz while the motherboard runs at its standard speed
so as not to mess up video, I/O, etc.

Somewhat similar to how a Windows PC with a cache works,
for example.  Most Windows PCs have a cache because
the CPU runs several times faster than the motherboard.

If he needs more information, email me and I'll see if I
can dig up more detailed explanations of the accelerators.