The Nintendo NES just got a working CD Drive thanks to this wild mod

The Nintendo Entertainment System was built for cartridges. Big grey ones, pushed into the front and pressed down before the console would do anything useful. The NESCD-001 changes that arrangement rather dramatically. It adds a working CD drive. This isn’t just a decorative optical drive bolted underneath an old NES, either. The custom system can read game data from a compact disc, play CD-quality audio alongside NES software and even handle small amounts of full-motion video. It uses the original console together with modern hardware, an EverDrive N8 Pro and a 40-pin IDE CD drive to make the whole thing work. The end result looks a little like an alternate version of the NES that Nintendo never made.

The CD drive sits underneath the NES

The NESCD-001 comes in a custom 3D-printed enclosure designed to sit directly below the original console. Its grey casing matches the general look of the NES, while the front adds a white disc tray, eject button and volume control. Inside, things get much more modern.

The system uses a Pacific Digital Mach 52 IDE CD drive connected to a custom circuit board built around an RP2350B microcontroller. There’s also a PCM5102 digital-to-analogue converter for handling audio. An EverDrive N8 Pro cartridge sits in the NES itself and plays a major role in getting games running.

The NES isn’t suddenly loading software straight from a CD in the same way a PlayStation or Sega Saturn would. Instead, the RP2350B reads an NES ROM stored on the disc and sends it over USB to the EverDrive N8 Pro. The EverDrive then runs that game through the actual NES hardware. So the CD drive provides the data, while the NES still does the job it was built to do.

Games can request extra data from the disc

Things get more interesting once a game starts running. Compatible NES software can ask the NESCD-001 for additional information stored on the CD. The microcontroller watches a specific section of memory and responds when the game requests something, such as music, graphical data or video frames.

That gives developers room to add things that would never fit comfortably inside a standard NES cartridge. Video is one example. The NESCD-001 can send frames through USB, while the FPGA inside the EverDrive N8 Pro helps move graphics into the NES’s video memory quickly enough to create moving images on screen.

Don’t expect PlayStation-quality cutscenes. The NES is still an NES, with all the hardware limits that come with it. But it works. Full-motion video support remains experimental, and it’s based on techniques that rapidly feed graphical tiles into the console’s CHR RAM. The CD simply gives the system far more data to pull from than an original cartridge could reasonably offer.

CD audio works alongside normal NES sound

Audio takes a different route. Instead of pushing everything through the USB connection, the CD drive sends digital audio through the PCM5102 converter and into the NES using the console’s expansion connection.

That means the game can continue producing normal NES sound effects and music while the CD hardware adds recorded audio on top. There’s even a physical volume control on the front of the NESCD-001. It’s a practical setup. Keeping CD audio separate also means USB bandwidth can stay focused on game data and graphics rather than having to carry everything at once.

Power has been tidied up as well. The expansion hardware uses a Molex connection, while a buck converter reduces the 12 V supply to around 9.5 V for the NES. In other words, the console and CD unit can run from a single external power source. You can still use the NES power adapter separately if needed.

Super Mario Bros. shows how it works

A modified version of Super Mario Bros. provides the clearest demonstration of what the NESCD-001 can actually do. The original game still runs much as you’d expect, but the CD adds recorded music and small video sequences that don’t exist in the standard cartridge version.

Remove the disc and those extra features stop. The NES game itself keeps going. That’s an important detail because it shows how the system splits the workload. The NES handles the game, while the CD expansion supplies additional material when the software asks for it. Standard NES software can still run through the EverDrive setup too, so the optical drive doesn’t completely replace the console’s normal way of loading games.

It’s a CD expansion, not a new console

The NESCD-001 isn’t trying to turn the NES into a completely different machine. Instead, it works around the hardware that’s already there. The IDE drive provides storage. The RP2350B manages communication. The EverDrive N8 Pro gets software and graphical data into the console, while separate audio hardware handles music from the disc.

Put those pieces together and you’ve got a functioning CD-based expansion for an 8-bit Nintendo system that was never designed with optical media in mind. It’s an unusual setup, but the idea is straightforward: keep the NES doing NES things, then use the CD drive to provide everything the original cartridge system can’t easily hold.

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