nsayer@uop.EDU (Nick Sayer) (07/15/89)
Forgive the widespread post, but I am being driven quite insane by this nagging problem. I am in the process of upping the speed on a PCPI Applicard for a friend of mine. I was able to do this successfully on my Applicard, with parts in my toolbox, but now my toolbox is empty, and I need to buy some more RAMs. I need 64Kx1 dynamic RAM chips, like 4164's. They need to be 100 ns. They need to work with 7 bit (128 cycle) refresh. I have called 20 different people (really! I counted!). Every single person I talked to apparently didn't know what I was talking about. As I talked to them, I could see (even through the phone!) this strange blank look come across their face. Am I the only one in the world who understands the difference between 7 and 8 bit refresh??? Am I going to have to buy 256K RAM chips and waste 192K of RAM to make this project go??? This project is for a Z-80. When the Z-80 refreshes, it puts a 7 bit number out on the high 7 bits of the address bus and generates a special refresh read signal. Some RAM chips will work just fine when only every second row is refreshed. These are called 7 bit refresh cycle RAMs. P-P-P-P-P-Please, eddie!!!! ------------------------------------------------------------------ Nick Sayer | nsayer@uop.edu | ...ucbvax!ucdavis!uop!nsayer Packet radio: N6QQQ @ WB6V | FredMail: NSAYER@MADERA%NORCAL Disclaimer: The BBC would like to appologise for that announcement Coming soon: quack!mrapple@uop.edu