Don’t Put That EPROM In Your Mouth!

[Jeremy] had some chips on hand that included EPROM.  We’re not talking about EEPROM, we mean EPROM that need a UV light source to erase. Most people don’t want to drop a few hundred dollars on a dedicated EPROM eraser, there must be another way.

Boy, EPROM really suck. But so do pacifiers and he already had a solution for exposing those to UV. He pulled out his $30 UV pacifier cleaner and tossed the chip inside. Two times through the cleaning cycle and the data was gone. We’ve looked into using UV LEDs to do the job but some experimentation shows that it doesn’t work. These pacifier cleaners are cheap and easy to get a hold of. The real question is are you still using chips that require UV for erasing?

Five Dollar Eprom Programmer


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.]