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More than you wanted to know about how Game Boy cartridges work
Allison Parrish I set out a while ago to make a Game Boy cartridge from scratch. This is not a novel goal; bootleg Game Boy cartridges have existed almost as long as the Game Boy itself has, and there are many third-party cartridges now available for purchase, or that have copyleft designs.
I guess this would have seemed like a big mess to Nintendo’s engineers at the time: routing the main board PCB would have been much less straightforward, and the CPU chip itself would need to be much larger—neither of which are desirable for a portable device with limited space for components. You’ll find RTC functionality in the smash-hit Acclaim Software classic, Mary Kate and Ashley: Pocket Planner, and also in gen 2 Pokémon games, which is the reason that you can only catch Ariados at night ( among other things). Instead, think of it as an anthology of strategies to help you overcome potential stumbling blocks on the road to making a cartridge from scratch, along with facts that might be non-obvious to people who are approaching the problem for the first time.
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