Image Map Image Map
Results 1 to 2 of 2

Thread: Mac 64k ROM question

  1. #1

    Default Mac 64k ROM question

    All --

    Today I was watching a recent video interview of Bill Atkinson and it inspired me to look at the code listing of the original Mac 64k ROM. I also have a copy of the global variables list compiled by Chuck Lukaszewski back in 1987. Anyway, in the globals listing, there is a reference to an "Alternate ROM" with a variable name of DiagROM at a base address of $00F80000. I know that the regular ROM is located at $00400000 after boot (and I think $0 upon reset so that the 68K can pick up the vectors).

    Anyway, to the real question...have images of these diagnostic ROMs ever surfaced? Are they designed to be used on the assembly line or when the development team was developing the original system board?


  2. #2
    Join Date
    Jun 2020
    Tennessee, USA


    Bumping this post because I'm curious to see if anyone knows anything - I personally have no idea about it. I've been meaning to poke around in the 128k ROM in the Plus and see if there's anything similar in it.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts