Image Map Image Map
Results 1 to 7 of 7

Thread: Can Anyone identify this MAC board?

  1. #1
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    1,488

    Default Can Anyone identify this MAC board?

    Someone offered me this board for sale but I dont know what it is neither do they. It looks like a compact mac upgrade board... maybe. Any ideas?s-l1600.jpg

  2. #2
    Join Date
    Apr 2015
    Location
    Austin, Texas
    Posts
    1,229

    Default

    I have a near identical board to that:

    https://i.imgur.com/ll5TTmg.jpg

    It's an upgrade for a Mac SE. You'll need a 25 MHz 68030 PGA CPU, an optional 68881/2 at 20/25 MHz and up to 4 MB of RAM to get it working.

  3. #3
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    1,488

    Default

    interesting. Does this expand the SE's system RAM or do you install the system RAM only to this card when using it? Also, what is the little grey connector on the back for?

  4. #4
    Join Date
    Apr 2015
    Location
    Austin, Texas
    Posts
    1,229

    Default

    It's been about 20 years since I last used this upgrade board, but I seem to recall it expanding the base system memory.

    The connector on the back is for an external monitor, those SIP memory chips on the side of the FPGA is video RAM. It's a monochrome output only, no color.

    I can't tell you what the pinout is though, as I lost the dongle for it years ago. I do remember it did output to a standard DE-15 VGA connector though. Some experimenting with a scope should tell you which pins are which.

    I'd love to experiment with it again, but I don't have a Mac SE anymore and haven't been able to negotiate for one in acceptable condition.

  5. #5
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    1,488

    Default

    did you ever test that video out to a vga monitor (or any monitor) successfully? Im sure I can find the pinout and make a connector.

    I thought the limitations of the system was 4MB, this board's architecture lets you expand past 4MB>?

  6. #6
    Join Date
    Oct 2008
    Location
    Kamloops, BC, Canada
    Posts
    5,291
    Blog Entries
    41

    Default

    I can see Bank Switching being helpful for overcoming memory limitations.
    = Excellent space heater

  7. #7
    Join Date
    Apr 2015
    Location
    Austin, Texas
    Posts
    1,229

    Default

    Quote Originally Posted by VERAULT View Post
    did you ever test that video out to a vga monitor (or any monitor) successfully? Im sure I can find the pinout and make a connector.
    Yeah, I was able to get the external monitor to work. IIRC it was just mirroring the internal display though.

    Quote Originally Posted by VERAULT View Post
    I thought the limitations of the system was 4MB, this board's architecture lets you expand past 4MB>?
    It's pretty trivial to expand system memory with an upgrade board like this, you have to remember that the 68030 is a 32 bit CPU which can address up to 4 GB of physical memory. They could have done several things to expand the memory in the system, including bank switching or using their own memory controller implemented in that big FPGA.

Bookmarks

Posting Permissions

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