Silly question: Unmodified Contra on Aladdin cartridge?

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Dwedit
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Silly question: Unmodified Contra on Aladdin cartridge?

Post by Dwedit »

Here is a silly question.
Would an unmodified version of Contra run correctly on an Aladdin Deck Enhancer system if it was put onto a similar cartridge board as Micro Machines?
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tepples
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Re: Silly question: Unmodified Contra on Aladdin cartridge?

Post by tepples »

In an unmodified front loader, it would probably blink. Codemasters cartridges use a software-controlled CIC stun circuit, and I assume the Aladdin is the same way. So hacking Contra from mapper 2 to mapper 71 would need a few changes.
  • A routine to operate the CIC stun circuit by writing to even and odd $E000-$FFFF.
  • Move all mapper writes during operation to $C000-$FFFF, preferably $C000-$DFFF. Writes to $8000-$BFFF in particular will not change the PRG bank.
Open Contra in FCEUX for Windows, set a breakpoint on writes to $8000-$BFFF, and play through. Does it stop?
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krzysiobal
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Re: Silly question: Unmodified Contra on Aladdin cartridge?

Post by krzysiobal »

Also dont forget that Codemaster's mapper does not have bus conflicts, UNROM does.
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