Available in kits on Tindie | Etsy

Available pre-assembled on Tindie | Etsy

Link to Assembly Manual

Link to Compatible Motherboards

The PC-64 can be built using either an Intel NUC7 or Asus PN51-series Mini PC. Both versions have interchangeable parts, with the only exception being the custom motherboard mount and rear I/O shield. The Intel NUC7 prototype build has a core i5-7260U dual-core processor and accepts 260-pin SO-DIMM RAM and SATA storage through the M.2 port. The Asus PN51 version is powered by a Ryzen 5500U processor with Radeon graphics and similarly supports SO-DIMM RAM and SATA storage via the M.2 port.

The original N64 controller ports are made functional by using two 2-port USB adapters for N64 controllers. Custom PCBs are used to route the controller port pins to the adapters, which then connect to the PC through an on-board USB hub. Power switch functionality was preserved using a circuit that converts the sliding action of the original switch into a momentary pulse generated by a 555 timer logic circuit.

The reset switch also works, but only on the Intel NUC7 version since the Asus PN51-series Mini PC's don't have provisions for a reset button. A spacer was designed for the Asus PN51 version to aesthetically hold the reset button in an un-pressed state. The original power indicator on the front of the console is wired into the PC's internal front panel header.

Custom 3D printed parts were designed to comfortably position the motherboard and PCBs, as well as provide covers for the cartridge slot, A/V ports, and an I/O shield.

Project Logs

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Product Update ~ May 2024
RetroModder • 05/15/2024 at 22:36 • 0 comments

This product update introduces new features added after the release of the PC-64 kits.
Intel NUC Support
A new bottom mount and rear I/O shield has been designed to work with the motherboard from an Intel NUC7i5BNK kit. These motherboards are more readily available and offer comparable performance to the Asus PN51 Mini PC's.
The controller port and controller adapter boards were re-designed to work with both Intel NUC and Asus PN51 versions, with the former now featuring a reset switch which the Intel NUC has provisions for.
Final Development Update ~ Oct. 2023
RetroModder • 10/23/2023 at 17:19 • 0 comments

This last update shows off the finalized PC mounting and PCBA design solutions for the Asus PN51 variant of this N64 console computer mod.

The main controller board was broken out into two halves. The controller port board and the controller adapter board. The controller port board consists of the power switch circuitry, power LED, and original controller ports which are then re-routed to the controller adapter board.

The controller adapter board contains two 2-port USB adapters for N64 controllers routed to a 2-port USB hub with ESD suppression circuitry.

The mounting brackets were also improved upon by using a single 3D printed mount for the mini PC and A/V port cover, and then another mount for the controller adapter board, rather than several different pieces.

Since the Asus PN51 does not have provisions for a reset switch, a block-off spacer was designed to keep the N64 Reset button propped up in its un-actuated position.

Lastly, an adapter was made for the controller adapter board USB cable because in some cases, the adapter board was having intermittent connection issues with the motherboard's onboard header. This problem did not persist when using the front or rear USB Type-A ports on a different computer, so this adapter should solve that issue.
Project Update ~ November 2021
RetroModder • 11/14/2021 at 23:33 • 0 comments

A custom PCB was designed to feature two 2-port N64-to-USB adapters routed to the original controller ports. Also included are the original reset and power switches, center power LED, and a custom circuit designed to send the proper shutdown signal to the Intel NUC. The board then bundles its I/O into a Molex Nano-Fit 16-pin header to interface with the motherboard. Status LEDs for the board power, motherboard power, power switch state, and reset switch state are also included. The control board's power switch logic circuitry is powered by a +5V auxiliary power header on the NUC, while the controller adapters still receive power through the 2-port USB 2.0 header.

The power switch requires some logic conversion to be able to properly power on and shut down the PC. A simple slide switch would not suffice, as the motherboard expects a pulse and not a constant signal. Twin 555 timers configured as one-shot pulse generators provide a single pulse for each "throw" of the slide switch. The output of each timer is then fed through an OR-gate, and then buffered to keep the circuit opto-isolated from the motherboard.

One minor flaw in this design is that it's possible for the power switch's position to become out-of-sync if operated too quickly, but this is easily rectified the next time the PC shuts down as you can unplug the device and move the switch back to the correct position.

Brackets were designed to adapt the stock N64 board mounts to the Intel NUC motherboard. In addition, an M.2-to-SATA adapter board can be mounted, as a full size 2.5" SSD was too large to comfortably fit in the case. A rear cover is also inserted behind the storage adapter to cover where the original AV port used to be accessed from.

A custom rear I/O shield matches the profile of where the stock AC adapter would normally plug into. Additional holes were added to mount the wireless antennas, and a vent allows the blower-style fan under the motherboard to exhaust out the rear of the case.