Monday, May 1, 2017

Decap #139 replacement: Mortal Kombat 4 U76

A bit back we processed PIC16C57 samples and discovered#139 (Invasion U76) was partially defective as received. We knew this before decap since PIC16C57 allows reading a 4 bit XOR of the 12 bit flash worlds even when protected. Unfortunately, only 2/4 word bits changed in the protected readout and only 3/12 word bits changed in the unprotected version.


Like Invasion, Mortal Kombat 4 is built on the Midway Zeus platform. With this in mind, a team member donated U76 from Mortal Kombat 4 to process as a replacement. Label off:



And here's it with the main EPROM masked against UV light:


Which allows safely erasing security fuses like in previous posts.

Stay tuned for our post on identifying and extracting #145 (Croupier)!

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3 comments:

  1. From an emulation standpoint, what does decapping and dumping this chip accomplish?

    ReplyDelete
    Replies
    1. It accomplishes more correct and better emulation.

      Delete
  2. Great Job!
    this was really needed since a very long time.

    ReplyDelete