Ghosts in the ROM

7826686642 Dd3Efbc891 O

7825085862-1

Ghosts in the ROM @ NYC Resistor.

While digging through dumps generated from the Apple Mac SE ROM images we noticed that there was a large amount of non-code, non-audio data. Adam Mayer tested different stride widths and found that at 67 bytes (536 pixels across) there appeared to be some sort of image data that clearly was a picture of people. The rest of the image was skewed and distorted, so we knew that it wasn’t stored as an uncompressed bitmap.

After some investigation, we were able to decode the scrambled mess above and turn it into the full image with a hidden message from “Thu, Nov 20, 1986“:

This is so cool.

Filed under: random — by adafruit, posted August 22, 2012 at 12:00 am


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1 Comment

  1. had some trouble clicking the source link, but this is a very old easter egg, I administered a network with quite a few Mac SE on it and remember this one. here’s the instructions on finding it with a full machine to work with:
    1) Hit the interrupt button on the programmer’s switch. A window with a ">"-prompt will open.

    2) Type in the following, without the quotes:
    "G 41D89A" (or is it "G 81D89A"?)

    Ta-daa! A few scanned-in photos of the entire Mac Plus crew right there on you screen, directly from the Rom.

    3) Hit the interrupt again and type "G FINDER", or just reboot the Mac. BTW, you can use "G FINDER" any time you want to reboot the OS shell.

    Comment by nowimold — August 22, 2012 @ 4:18 pm

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