EPROM Speed

[TommyE]

Hello

I'm picking up my interest in the VIC-20, and I have burned out a few games to EPROMS.
Most work great, but I see that some EPROMS I have (Various manufacturers) don't work with the VIC20.

I wonder, does anyone know the max speed for an EPROM to be used successfully on the cartridge port?

Regards
TommyE

[srowe]

EPROMs of many different sizes and speeds have been seen to work on the expansion port. The only place I'm aware of problems is when trying to replace the character ROM with an EPROM. Where have you has problems?

[TommyE]

Hi

I’m burning games eprom that I use on a few blank cartridges I have.

I have look up the specs, and it seems that
the eproms that does not work are 250ns rated.

All my 200ns and lower works.
So it seems that 200ns is the max I can use.

Tommy

[srowe]

OK, perhaps you're right. I've just gone through my collection of EPROMs and all the marked ones are 200ns or faster. I was sure back in the 80s I used 450ns chips, but perhaps I'm mistaken.