NES:NESRGB

The NESRGB is a mod designed by Tim Worthington to improve the video quality of the NES and Famicom. Released in 2013, it was the first RGB output solution for the NES/Famicom that did not require scavenging the RGB PPU from a PlayChoice-10 or Vs. board.

The following information and images have been gathered from Tim's website, with their permission.

Description

Most unmodified NES and Famicom consoles only support composite and RF (radio frequency) video output, with the original Famicom and top loader NES only having RF output. The NESRGB is an internal mod that adds RGB and S-video outputs to the NES and Famicom.

The mod features a user-selectable palette system that allows the user to change the color scheme of the video output to suit their preference. For more information about NES palettes, see FirebrandX's NES Palette Project page.

Features

• Generates RGB, S-video (encoded from RGB), and composite video (encoded from RGB) signals
• No latency (video timing is maintained)
• Built in audio and video amplifiers
• Compatible with NTSC and PAL consoles
• Compatible with NES, Famicom, AV Famicom, and Twin Famicom consoles
• User selectable color palettes
• Upgradable firmware via JTAG programmer
• Can be switched off to allow the use of the original composite video output from the PPU

Technical Details

The NESRGB board contains an Altera CPLD (Complex Programmable Logic Device) that utilizes the NES's PPU (Picture Processing Unit) and CPU to generate an RGB video signal.

Note About Jitter

The timing of the NES/Famicom's video signal is slightly unusual and runs slightly under the standard 60 Hz in an attempt to reduce video artifacting. However, this signal is not compatible with all modern displays and may cause some flickering at the top of the screen. Original versions of the NESRGB did not address this and so required a "de-jitter" mod when used on sensitive displays. Beginning with hardware version 2, the NESRGB incorporates a de-jitter function in its firmware. Instructions on how to add a de-jitter mod to older NESRGB revisions can be found here on Tim Worthington's website.

Note About Hardware Version 3

Palettes cannot be selected by a switch; only one palette is supported at a time with hardware version 3. However there are different firmware files each with a different palette, and so users can flash different firmware to select different palettes.

Materials Required

• Phillips head screwdriver
• 4.5 mm gamebit screwdriver (required for NES top loader and AV Famicom)
• Soldering iron, solder, flux, wire, and wire stripper
• Desoldering gun (not totally required, but highly recommended as it makes removing the PPU much easier)
• Drill with step bits (required if adding additional connectors)

Installation

Front Loading NES

See the official written documentation.

Original Famicom

See the official written documentation.

AV Famicom

See the official written documentation.

There is also an AV Famicom quick-solder board (QSB) and an additional process to remove jailbars as noted on the LaserBear website.

Top Loading NES

See the official written documentation.

Twin Famicom

See the official written documentation.

Troubleshooting/Notes

See the official errata and firmware download page.