68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.
Macintosh Performa 200
Posted by: mrnateytatey on 2019-09-01 03:31:12
I apologize if this isn't posted in the correct location or forum. But i'm tired of seeing this thing sit around.
I love this machine, when I first used it at my neighbors house it was so much fun, then I finally bought it off of him, with the dot matrix printer, keyboard and mouse. I decided to crack the case open to fix some boot issues that I had noticed from what I thought was coming from the ROM chips, However like a dumba** I inserted them wrong and may or may not of fried them. Im not sure, what can I do, anything I can try upon boot, are there alternatives for the ROM chips, replacements, or can I use a Mac Classic Mobo from ebay?
Some times the screen turns on with alternating black and white bars.

photo_2019-09-01_04-21-55.jpg photo_2019-09-01_04-22-07.jpg

Many Thanks for any help, Nate.
Posted by: Crutch on 2019-09-01 06:25:30
The Performa 200 is the same as the Classic II so you could definitely try a Classic II motherboard or ROMs, they would be identical.  It seems pretty surprising to me though that one could fry the ROMs by putting them in the wrong way, since all they’d be getting is 5V in the wrong spot?  (I’ve never done that but I’ve definitely put a 68882 in the wrong way and although it got really hot, it worked fine once I realized and corrected my mistake!)
Posted by: mrnateytatey on 2019-09-01 11:15:42
It was a while ago, but If I remember correctly the ROM chips did get pretty hot.
Is there anywhere that I can find parts, especially for these older macs?
The mobo I found on ebay "Apple Macintosh Classic Mac Computer Board 820-0390-B"

The power and video connector look similar if not the same.

Many Thanks, Nate

photo_2019-09-01_12-09-40.jpg
Posted by: Crutch on 2019-09-01 13:42:57
The motherboard is probably close to the same, but I am pretty sure the Classic II had different ROMs than the Classic.  I’ve never had a Classic though so I’m not certain.
1