manga: the 'C02 also added some new instructions. ProDOS versions 2.0 and later used them to save memory and gain some performance.

LN: I have a working ROM 3 but no way to get data off of it other than by sight. (The 800k floppy drive works but I don't have a Mac of the required vintage to be able to convert that to a PC floppy right now - maybe I'll grab a cheap Classic off eBay or something).

The nice thing about that MCU is that it's the 8-bit parent of the M377xx series I emulated in MAME (except the 377xx added a second accumulator, which is kind of heresy but also useful).