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Macintosh Plus - Sad Mac - 01FA00


Active member
I don't know the history of this machine but it's really clean inside and out.
At boot the machine chimes but displays a Sad Mac error 01FA00.
Searching around and it seems like a Mac Plus should not throw an 01xxxx error.

I've tried swapping the ram chips around but got the same result.
When removing 2 simms from bank B I get a cycling pattern on the screen and no boot chime. Guessing because the Plus needs 1mb minimum to operate and removing 2 chips from bank B drops it to only 512k of ram?
Ram size resister looks correct for my 1mb setup.

Anyone run into this specific scenario before?

Thanks in advance!


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Well-known member
A 01 error means that there is a ROM error. Plus ROMs are sometimes defect.
You can burn new ROMs with an eprom burner.


Well-known member
There are different versions of ROMs. You have to look, which version you have.
And the plus ROMs are split into two files (high and low).
Here you can find two windows programs to split and compare roms.