More NESessity v1.3 PCBs and parts kits will be available Friday, August 20th.

International shipping will resume August 27th.

I have temporarily stopped international shipping to all countries except Canada due to long shipping times as well as some packages being returned or lost. Sorry for any inconvenience.

Recently updated assembly guide is available to download in .rtf format. Digikey parts list has been updated 7/23/21 and is available to download in .pdf format.

NEW FEATURE: Includes A/V + power board with a Genesis 2 compatible RGB video connector, s-video, and composite video that requires no cutting or drilling of your original NES system case. (NESRGB required)

Upgrade and/or repair your 30 year old Nintendo NES with this new design motherboard.

The NESessity is a top quality replacement motherboard for your front loader NES console with a variety of new features and easy customization options. Circuit is based on a complete reverse engineering of the original system for 100% pixel prefect gameplay and compatibility. Designed for easy assembly, all components are through hole (with the exception of two SOIC chips.)

3 circuit boards are included: The NESessity v1.3 motherboard and the A/V + power PCB that replaces the original RF modulator box. Two versions of the A/V + power board are included: composite video only or RGB, s-video, and composite connectors. RGB and s-video output is only available when building the NESessity with the NESRGB add on.

CPU and PPU chips are required to be de-soldered and removed from the original NES. Aftermarket clone chips are readily available from Aliexpress and can also be used (although these will have sound issues and are not compatible with some games.)

• CPU: RP2A03 (original) or UA6527 (clone)
• PPU: RP2C02 (original) or UA6528 (clone)

The NESessity is designed to install in NTSC systems. Building a PAL compatible system is possible by using the correct PAL CPU (RP2A07) and PPU (RP2C07) chips along with a 26.601712 MHz crystal.

Famicom games can be played by using a readily available cartridge adapter.

Features:

• Works and installs just like the original part in your original front loader console.
• Region free; Famicom games require cartridge adapter.
• 15p Famicom expansion port replaces the original 48p NES expansion port.
• Adjustable stereo sound with auxiliary sound input from NES cartridge pin 54.
• Can be assembled with or without original RF shielding.
• No lockout chip; uses reset circuit from top loader NES.
• PPU is in same location as original NES so any video mods that fit original will fit NESessity. Compatible with NESRGB and Hi Def NES video mods.
• Can use original AC NES power adapter or modern 12v DC power adapter.
• No modification to the original NES case required.
• Works with original power / reset button PCB (requires small modification.)
• Compatible with Famicom Light Gun, 3D Glasses, 4 player adapter, and BASIC keyboard. Some accessories may require a db15 extension cable to physically plug them in.
• Supports Famicom microphone and has LED to indicate when input is active.
• Ventilation holes for improved cooling.
• Premium quality PCBs have thick 2oz copper finish.

What's included?

• unassembled NESessity v1.3 motherboard
• two unassembled power + A/V PCBs (RGB and composite versions)

What's required?

• Original NES CPU and PPU chips (recommended) or aftermarket clone chips
• Parts listed on B.O.M. Almost everything is available from Digikey
• (Optional) NESRGB kit for RGB & s-video
• (Optional) Reused 5 pin connector for power/reset PCB
• Reused crystal from original NES (this can be hard to find new)
• The original front loader NES system case

Download and read the assembly guide before building your NESessity.

Thanks for looking!