In message <200407271720.i6RHKMcu001535(a)everymail-A16-C02.everymail.net>
wolfgang(a)eichberger.org wrote:
first I want to thank you for your nice and fast help
with
my Commodore Pet ROM
problem.
You're welcome :)
But after lots of time googling around I haven't
found much stuff
about this old eproms. Okay, I have at least a bunch of datasheets and some
schematics where ex. the 2532 were used and learned a lot of early 1980's
hardware basics :) But I could not find some schematics (and software) of
Eprom programmers dedicated to this chips. My (maybe dumb) question: 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? This would be a great project for rainy winter days :)
Okay. You're going to need:
1x 4040 12-bit binary counter IC
1x 74LS573 tristate data latch
1x 74LS244 bus transceiver
1x 25V power supply
1x socket for EPROM
1x 25-way D-type connector
+ misc parts (protoboard, resistors, capacitors, etc.)
The idea is that you use the 4040 to run the EPROM's address lines, then feed
data in with the LS573, give the EPROM a program pulse, read the data back,
then move on to the next byte. If you want a schematic, I can draw you one up
later. Let me know off-list.
Later.
--
Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem(a)dsl.pipex.com | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.dsl.pipex.com/ | 48xCD, ARCINv6c IDE, SCSI
... (C)ontrol (A)lt (B)ye