I assume you have a PC with a paralell port. There used to be quite a few
programmers that used the output of a paralell port to burn EPROMS. I have
built a couple of them from scratch and they were pretty easy to built just
using perf board and point to point wiring. Unfortunately I no longer have
these burners or the schematics. Electronics mags in the 70s, 80s had a lots
of them so you may want to go to your local library and brows the fiche. I
have built several compters using Z80 and had a blast doing it. It is a
worth while learnuing experience.


"Mr. Phil" wrote in message
news
I've looked at the PIC microcontrollers before, but we have a whole
basement
full of ancient computers that we're taking parts from and we're trying to
build this out of parts we already have. It's looks like it's more
difficult to wire up than a PIC would be, but we're up for the challenge.


-Phil


I suggest that you try one of these alternatives:
- patch up your system so you can write to the RAM from a PC parallel
port
- use a FLASH ROM, build your own (PC parallel port based?) programmer
for it
- forget the Z80, use a micrcocontroller with build-in FLASH (PIC, AVR
or 8051)



Wouter van Ooijen