Macintosh Plus ROM Chips in Macintosh 512K

[mikemike690]

I've just brought a Macintosh Plus and soon to buy Macintosh 512K, the Plus has corrosion from battery leakage but I'm pretty sure the ROM chips will still be good hopefully, am I able to unsolder these Plus chips and solder them into my 512K? Thanks.

 

[MacTech68]

Yes, indeed you can, but you should really swap them as a pair. There are two ROMs (HI and LOW), and the revisions of each one need to match a certain pairing.

However, to find out which ROM is bad, you should be able to swap one at a time.

It will create other odd errors if you have an unmatched pairing as a permanent fix.