LCIII EPROM?

[frontein1]

Curious if anyone has tried replacing the stock LCIII ROM ICs with EPROMs? I'm thinking something along the lines of the 27C400, but I am trying to do a pin-by-pin comparison right now.

Has anyone done any research on this before? And if so willing to share?

 

[finkmac]

not much to research. you can replace any mac [P]ROM with an EPROM or EEPROM equivalent

 

[Boctor]

This research (authored by a user here!) helped me figure out which ROMs were compatible with my IIcx and IIci, and gave enough introductory info to help me replace my failed mask ROMs with cheaper flash ones... After a bit more help from other users here, who alerted me to the obvious but easily-solved pitfall I forgot about: Common flash chips like the SST39SF010 need the Write Enable pin to be high when in the Mac, to enable reading. Other than that, they're perfect.

 

[frontein1]

Thank you @finkmac and @Boctor!

Have the ICs and programmer in the mail. Looking forward to having some fun with the LCIII that I originally purchased from @jmacz.

 

[jmacz]

Thank you @finkmac and @Boctor!

Have the ICs and programmer in the mail. Looking forward to having some fun with the LCIII that I originally purchased from @jmacz.

Nice, have fun!

 

[finkmac]

Thank you @finkmac and @Boctor!

Have the ICs and programmer in the mail. Looking forward to having some fun with the LCIII that I originally purchased from @jmacz.

consider investing in an EPROM eraser too!

protip: the phone sanitizers with UV bulbs (not LEDs) work VERY well.
they can also be had fairly cheaply and are generally higher quality than the generic "eprom eraser" deathtraps you can get on amazon and such.