How can I modify my ZipGS for more cache and more speed?
The process described below is very simple. It aims for a speed of 12.5MHz (or better) with 64k cache. First, you will need one of the new Western Design Center 14MHz 65C816’s. Students, teachers, and professors can order the IC in single quantities directly from WDC ( ). Otherwise, the minimum order is $100. Price is about $20 each. adapters: Nearly all of the newer, faster 32k x 8 SRAMs are in skinny 300-mil packages. If you would rather not modify your ZipGS for the skinny SRAMs, Digi-Key stocks 28-pin 300-mil to 600-mil adapter sockets from Aries Electronics for about $12 each (Aries no. 1106396-28). You can plug a 28 pin SRAM into the 300-mil adapter socket and the adapter in turn plugs into the 600-mil socket on the Zip. (If you have some spare sockets lying around, you can build your own cheap, but that’s another story.) 2-4 32k x 8 SRAM chips: There are many sources for 32k x 8 SRAMs and several types that will work. I got mine (HM62832-15, $5 each) from JDR Microdevices. You’l
