Old EPROM questions again, EPROM Programmer

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Wed Jul 28 18:23:15 2004

>
> > Does anyone have some schematics and software (would be great) for a
> > little homebrewed Eprom Programmer which works with a standard PC
> > parallel-port or ISA slot?
>
> I have a hardware/software design for a simple EPROM programmer on my
> site ... unfortunately, it was designed years ago when I was still fairly
> new at hardware design and it shows ... Works well however and I still
> use one of them from time to time (quicker and easier than my 29B).
>
> It's completely stand-alone with a 8-digit LED display and a keypad. It
> can upload/download Intel or Motorola HEX format data via a serial port,
> and also has a "remote" mode for total computer control.
>
> It only does 2716, 2732, 2764, 27128 and 27256 family devices (all I
> needed at the time), although you could design adapters and modify the
> code to support other devices if you wanted (I did one for 8051's at
> one point).
>
> Parts might be a bit hard to find now - uses a 6809 CPU, 6821 PIA, a 6551
> UART, a few 6264 SRAM's, a handful of latches and 3-4 relays to move the

And thereing lies the problem. Presumably you need to program an EPROM
with the firmware for this 6809. Which is somewhat hard without a
programmer :-)...

I built my first EPROM programmer about 18 years ago. Programs
2716-27128, using the 'slow' algorithm. It doesn't even handle 12.5V
parts (I should add that feature!). 3 hand-wired boards of mostly TTL,
with a 40 pin AY-3-1015 UART in the middle. Oh yes, it's an EPROM
emulator as well, for the same types of EPROMs.

My idea was to use this device to develop and burn the firmware for a
microprocessor-controlled programmer, but I never got round to it (and I
picked up a number of interesting commerical programmers too). One day,
perhaps...

-tony
Received on Wed Jul 28 2004 - 18:23:15 BST