How to Run ‘Doom’ on an NES
June 5, 2019Doom is one of my favorite games, which is convenient because it will run on almost any device. Digital cameras, old Nokia phones, a Zune, you name it. If it can be connected to a screen, someone has probably modded it to run Doom, and if they haven't, someone is probably working on it.
The original Nintendo Entertainment System is a notable exception to the rule, but an understandable one given that it's just not powerful enough. First released in Japan in 1983, the NES had 2kb of RAM and was designed to run 8-bit games, while 1993's Doom is one of the earliest 3D games that required 8mb of RAM. These immutable facts did not prevent YouTuber TheRasteri from getting an NES to run Doom...sort of.
What TheRasteri had done here is a very neat trick and bit of hardware modding. The NES, which is not modified, is indeed running the full version of Doom, but the cartridge is not really a Doom NES cartridge. It's a Raspberry Pi that's running Doom and hijacking the NES's graphic memory to inject Doom's graphics straight into the NES's picture processing unit. Basically, the Raspberry Pi is doing all the work and just passing the signal through the NES.
You might consider this cheating because the modified cartridge is doing more work than the console, but as TheRasteri correctly notes, Nintendo has done this itself in the past. The original Star Fox for the SNES was able to push revolutionary 3D graphics at the time because the cartridge the powerful Super FX chip that did the heavy lifting, not the console itself.
TheRasteri said he got the idea for this mod from howchoo who put a Raspberry Pi into an old NES cartridge and loaded it with thousands of ROMs to create a neat-looking emulation machine.
Sadly we'll have to wait a bit before we can copy TheRasteri's project to run Doom on our NES at home. He said that he still wants to work out a few bugs and improve the graphics quality before he releases his project, but you can subscribe to his YouTube channel for updates.