N64 SP – Portable Nintendo 64 Mod

Posted 6 Apr 2020 by Squid

The Game Boy Advance arrived on the scene just about at the time the N64 was fading out. The GBA SP arrived a couple of years later (and was the first GBA that I had). The one thing I would have never expected to see is a N64 SP, a Game Boy Advance SP that can play Nintendo 64 games.

Transcript

Hi, I’m Gman and this is the N64 SP. It is a custom N64 portable using a real N64 motherboard with an enclosed cartridge slot for full game compatibility.

The case design is a clamshell type with a 5 inch screen and it uses a 4250 mAh battery cell which lasts about 2 hours on a charge. It uses USB C power delivery charging and it can be played while plugged in for longer sessions.

A Nintendo 64 portable takes a real N64 motherboard, a controller, portable screen, batteries and packs it all into a compact case. They’ve been made for many years now, and was my first portable project that got me hooked in the hobby after discovering that people were making these things.

An N64 portable is still relevant due to emulation cannot beat real hardware. Raspberry Pi and other emulation machines struggle with compatibility. Also the satisfaction of inserting your real game cartridges is great.

The concept of this portable came after some recent development in N64 motherboard trimming. Modders have pondered for years whether or not it was possible to rewire the PIF IC. Turns out it is. PIF, the chip responsible for interfacing with controller and cartridges security chips is located on the far edge of the motherboard. It has always limited how small we can trim the motherboard and relocating allows me to make the motherboard smaller than ever possible. It’s been a dream of mine to make a small N64 portable with a fully enclosed cartridge slot, so I went off that and designed the whole case to look like a cartridge. The case is 3D-printed on my Pruca mk3 and the buttons are resin printed on a form too.

I used a spring hinge from a 3DS which can snap the screen to different viewing angles. The internals are made streamlined with an all-in-one PCB. The heart of the board is the battery management which handles charging and system power. There is special circuitry to allow USB C power delivery charging. This allows higher voltage over PD chargers for faster charging.

I also incorporated a custom I2s digital audio amp. This bypasses the normal analogue audio for crystal-clear digital audio. Lastly there is the N64 controller emulator which is being developed by my friend Aurelio, who also brought us the Gamecube controller emulator, GC+. The PCB is a 2-layer PCB by JLCPCB. I use their services for all my prototypes and along with their great pcb quality, their delivery is super-fast. This video was sponsored by them and there is a link in the description where you can order your own PCB designs.

The screen is a 5-inch LCD with VGA input using the UltraVGA mod kit designed by Marshall. The mod uses an FPGA on the N64 digital video signal to output it as crisp VGA. It took the awesome features of this ultra HDMI N64 mod and redesigned it to be used in N64 portables. The result is amazing.

This portable is made to show off what’s not possible for modern N64 prtablising and I’m very excited for what’s to come. Bitbuilt team will be working on a definitive N64 trimming guide on how to relocate the PIP IC as well as bringing the N64 controller emulator to the store. Thanks for watching.

There have been many portable Nintendo 64 consoles in the past, but there are a few things that set the N64 SP aside from the others.

First of all, it made a major breakthough in N64 modding (according to the author), which was to be able to relocate the PIF chip. The PIF chip is what controls the region locking on the console, as well as input devices. Here it is on a normal N64:

As you can see, the whole right side of the N64 is taken up by this chip, the audio amplifier (far right), a bunch of capacitors and the reset button. Being able to move this around allows the modder to make the console much thinner. He printed a new custom PCB to arrange them as needed, but I’m not going to get into that since it’s way above my head.

The N64 SP plays cartridges that are inserted on the back of the console, unlike the GBA SP, which has you insert them through the port on the front of the console.

It charges its 2-hour battery via USB C, which enables the console to charge quickly and allows the player to play while it’s charging.

There is more to the N64 SP, but those are the things that I think define this mod the best. Have a look at the video for the full breakdown. There’s also some previews of the mod with some nice PCB shots and diagrams on their website. An interesting read if you have some time.