Re: Apple II ROM Chips

[Patrick Schaefer <PSchaefer@epost.de>]

David Wilson schrieb:

> There are a lot of places where 341 and 342 prefixes are confused
> in Apple documents or systems. Often you can just treat them both
> as the same part.

One means EPROM, the other mask ROM. However, Apple seems not to care
very much for this convention. The software is identical in both cases.
Sometimes they even have different ROM revisions ("A", "B") with the
same contents.

> >> 341-0036 ][plus character ROM
> >    What is this?
> 
> Presumably the character generator chip that contains the bit maps
> of the characters as used in text mode. Early ][/][+ computers used
> a 2513 chargen while later models (version 7 and RFI boards?) used
> a 2716 pinout compatible ROM.

Exactly. And the IIc, IIe character generator chips hold two character
sets (US and foreign) with ][|{}\ and their local equivalent. 


Patrick