Not only did pirate companies in Asia flood the market with pirated cartridges for every Famicom game you can think of, but they also released a number of devices you could use to dump and write Famicom games all on your own. One such device is the Fami-Corder, and the process for dumping and writing games is simple using this device.
Essentially what happens is this: You take one of the specially-made, blank cartridges that comes with the Fami-Corder. You pop it into one slot. Then, you pop a licensed cartridge with a game on it into the other slot. You hit the Start button and the game begins the process of “writing” — as the Fami-Corder calls it — the game onto the blank cart. It’s that easy.
The only downside to the Fami-Corder, or any such device, is that it doesn’t allow you to write complex games. The cartridges these devices use have a defined mapper ability and don’t allow you to write games beyond that. The boards inside use EPROMs, which allow whatever you write onto them to be erased with light. That’s why these carts have holes in them and the chips (EPROMs) have “windows” in them. The hole are covered with stickers to keep the chips from getting erased. EPROMs are commonly found in prototype carts.
Devices like the Fami-Corder sell for around $80 brand new. For gamers into development and technical projects, this is a must-have, just to play around with it for a while. It wouldn’t be such a bad thing to write your own games, even if you’re writing games you already own.