Five dollar eprom programmer
posted Nov 8th 2006 10:22am by Will O'Brienfiled under: misc hacks
A couple years ago I spent a good week wiring up a fairly complex EPROM programmer so I could burn a prom for my jeeps EFI system. Today I ran across this $5 version. build built by Jay Kominek He uses shift registers to handle the addressing and IO lines, all driven directly by the parallel port. There’s no way to escape the number of pins that have to be wired up, but the schematic itself is pretty simple.
[By the way, arcade supply shops are a great source for cheap UV erase EPROMS.]
[Update: I'd forgotten about the voltage change (3 vs 5 if I remember) needed to write UV EPROMS vs EEPROMS. With a little mod, you can certainly use this for EPROMS as well.]
Great hack! I had wanted to build something similar, basically a parallel to serial EEPROM adapter. Using some 7400 or 4000 series shift registers I could reasonably approximate a simplified I2C bus, and get to reuse all the old EPROM and EEPROM chips I have. The goal was originally intended for a Basic Stamp, but could work with a PIC or a standard serial port with a little more work. If anybody knows how to do the whole I2C bus approximation in discrete logic easily, please post. Implementing the automatic address shift, rollover, and controll registers seems pretty hard without a micro of some sort.
Posted at 11:58 pm on Nov 8th, 2006 by Tillin9