Enlarge / A look inside the circuitry of a “decapped” arcade chip. (credit: Caps0ff)
The community behind the Multiple Arcade Machine Emulator (MAME) has gone to great lengths to preserve thousands of arcade games run on hundreds of different chipsets through emulation over the years. That preservation effort has now grown to include the physical opening of DRM-protected chips in order to view the raw code written inside them—and it’s an effort that could use your crowdsourced help.
While dumping the raw code from many arcade chips is a simple process, plenty of titles have remained undumped and unemulated because of digital-rights-management code that prevents the ROM files from being easily copied off of the base integrated circuit chips. For some of those protected chips, the decapping process can be used as a DRM workaround by literally removing the chip’s “cap” with nitric acid and acetone.
With the underlying circuit paths exposed within the chip, there are a few potential ways to get at the raw code. For some chips, a bit of quick soldering to that exposed circuitry can allow for a dumped file that gets around any DRM further down the line. In the case of chips that use a non-rewritable Mask ROM, though, the decappers can actually look through a microscope (or high-resolution scan) to see the raw zeroes and ones that make up the otherwise protected ROM code.
Read 5 remaining paragraphs | Comments

Leave a Reply