What is the difference between EPROM and EEPROM?

[sku_u]

I wasn't sure where to post this question, but I've seen people refer to both EPROMS and EEPROMS. What is an EEPROM?

[CPUWIZ]

EEPROM's can be erased electrically, they don't have a window for UV exposure.

[Susuwatari]

EPROM requires exposure to short wave UV to be erased and reporgrammed. EEPROM can be reprogrammed selectively (ie just one byte in the middle)

 

EEPROM are often called flash ROM but it's not quite the same thing.

[Zaxxon]

I have EPROMS in one of my ADAMs and in a pinball machine. They both are very old and the tape/label stickers covering the windows have dried up and fallen off at some time. Do I need to worry about the info on them being erased or has it already been damaged from exposure to sunlight (through windows) and light from lightbulbs or will it only get erased if I deliberately put it under a UV light?

[Susuwatari]

Yes but it would be weeks if not months from light bulbs i ndoor. Some windows also have UV block so sunlight wouldn't do much. Slap a piece of tape over the EPROM window.

 

Considering the age of Adam hardware, EPROM is more likely to fail from old age than from accidental exposure,