Video Output
Previous versions of the NESRGB could output RGB, s-video, and composite video signals simultaniously. Version 5 can only output one video signal at a time. It has four video video output modes - RGB, component, s-video, and composite. It can detect which signals are being loaded (that is, connected to a TV/display via a cable) at power up and sets the appropriate video output mode automatically. The video mode can also be set manually via the controller.| Pad name | Description | RGB mode | Component mode | S-video mode | Composite mode |
| C | Chroma output | Red* | Pr* | Chroma | - |
| Y | Luma output | Sync (75 ohm) | Luma (Y) | Luma | - |
| VS | Video/sync output | Sync (75 ohm) | Composite video* | Composite video* | Composite video |
| B | Blue/Pb output | Blue | Pb | - | - |
| G | Green/Luma output | Green | Luma (Y) | Luma* | - |
| R | Red/Pr output | Red | Pr | Chroma* | - |
| CS# | Sync (TTL) output | Sync (TTL) | Sync (TTL) | Sync (TTL) | - |
The are two main operating modes of a NESRGB board - normal mode (which is what I recommend) and legacy mode. Normal allows changes to the palette and addition features via the controller or an on-screen menu. Legacy allows changes to the palette via mechanical switch only. Which mode you use is decided at the time of installation. Set normal mode by closing solder jumper JP1, for legacy mode leave it unsoldered. This document describes Normal mode, the Legacy mode operation is described here.
You can troubleshoot the cable detection with the debug LEDs on the NESRGB board. The debug LEDs can be sent to show different things, but it is set to cable detection mode by default. If this has been changed, you can set this via the menu or by pressing SW1, the tactile switch on the NESRGB board if it is fitted. The LEDs are labelled G R 4 3 2 1 0. There are two sets of information that alternates every two seconds. The load detection results are shown on the LEDs with a twinkling effect, so you can differentiate the two sets. In the video mode set, G and R LEDs are always off, 4 is on when automatic cable detection is enabled and off if manually set, LEDs 3, 2, 1, 0 show the current video mode.
The load detection is performed once at console power up. The results are not used for anything if the video mode is manually set, but it still may be useful for checking the RGB cable and wiring.
| Description | LED-G | LED-R | LED-4 | LED-3 | LED-2 | LED-1 | LED-0 |
| Set 1 (LEDs on solid): Video mode | - | - | Automatic mode | RGB | Component | S-video | Composite |
| Set 2 (LEDs twinkle): Load detection results | Y | VS | B | G | R | CS# | OVIN |
Some consoles have dedicated composite video outputs such as the front loading NES and the Famicom Twin. This will work normally when the NESRGB board is in composite video mode. In all other modes it will output a grey and white picture. On the front loading NES only, the original composite video output can be load tested. To do this solder a wire between the OVIN pad and the composite video signal at the connector in the RF box. Then go through the calibration procedure documented in the installation guide.
Nintendo Mult-out Connections
AV Famicom consoles have a multi-out connector present, and it's a popular option for AV connections other console models. There is a standard way to connect the NESRGB board to a Nintendo style multi-out socket which is described in the table below. The J1 is an 18 pin 0.5mm pitch FFC connector with the same pin arrangement as the Voultar QSB board sold by Laser Bear.| Multi-out pin nr. | NESRGB solder pad | J1 FFC connector | Description |
| 1 | R | 18 |
Red video output |
| 2 | G | 17 |
Green video output |
| 3 | CS# | 15 |
TTL composite sync |
| 4 | B | 16 |
Blue video output |
| 5 | GND | 2,4,8,9,10,12,14 |
Ground |
| 6 | GND | 2,4,8,9,10,12,14 | Ground |
| 7 | Y | 11 |
S-video luma (s-video mode) or sync (RGB mode) |
| 8 | C | 13 |
S-video chroma |
| 9 | VS | 5 |
Composite video (composite mode) or sync (RGB mode) |
| 10 | +5V | 6,7 |
5V power output |
| 11 | AO | 1 |
Audio left output |
| 12 | AO | 3 |
Audio right output |
| General multi-out cables available | Compatible with NESRGB? |
| RGB cable for Japanese/American (NTSC) Super Nintendo | Yes |
| RGB cable for European (PAL) Super Nintendo | No |
| RGB cable for European (PAL) Gamecube | Maybe |
| S-video A/V cable for Japanese/American (NTSC) Super Nintendo, N64 | Yes |
| S-video A/V cable for European (PAL) Super Nintendo, N64 | No |
| Composite A/V cable for Japanese/American (NTSC) Super Nintendo, N64, Gamecube | Yes |
| Composite A/V cable for European (PAL) Super Nintendo, N64, Gamecube | No |
Multi-out cables for PAL and NTSC region consoles are incompatible by design. Nintendo was very serious about region locking their peripherals in those days. Generally speaking, just avoid Nintendo cables made specifically for PAL consoles and you will be OK.
For composite and s-video cable, detecting is easy. There is only one component video cable on the market, so that makes it simple. RGB cables on the other have an incredible variety of different designs. As far as cable detection goes, the cables with video drivers inside such as the Universal RGB SCART cable from Retro Gaming Cables, and the HD Retrovision cable (which is an RGB cable with a component video converter circuit inside) do not load the video signal and as such cannot be detected. Set Audomatic configuration to 0 or 1 if you use a cable like this. This way it will set the video mode to RGB when there is no cable detected.
There also is a detection probelm where cables that have a sync separator inside (Retro Gaming Cables were selling these for some time, not sure if they still do) does not load any of the available sync outputs so will look like a component video cable to the auto detector. Set the Automatic configuration to 1 if you have this problem.
| Specific multi-out cables |
Detected as | Y |
VS |
B |
G |
R |
CS# |
| RGB cable with active video driver circuit - example from retrogamingcables.co.uk, HD Retrovision | undetectable, default* | ||||||
| RGB cable with sync separator circuit - example from retrogamingcables.co.uk | RGB/component** | x |
x |
x |
|||
| RGB cable with composite video as sync - example
from rightsprite.co.uk |
RGB | x |
x |
x |
x |
||
| RGB cable with luma (Y) as sync - example
from retro-access.com |
RGB | x |
x |
x |
x |
||
| RGB cable with TTL sync as sync (with or without series
resistor) - example from
oldskoolconsoles.com |
RGB | x |
x |
x |
x |
||
| RGB cable with TTL sync as sync (but sync is unterminated on the display) - ex. retrogamingcables.co.uk | RGB/component** | x |
x |
x |
|||
| Component cable connected to G (for Y), R (for Pr), B (for Pb) - example from ebay.com.au | RGB/component** | x | x | x | |||
| Component cable connected to Y (for Y), R (for Pr), B (for Pb) - D.I.Y. only | component | x | x | x | |||
| S-video - example from retrotink.com | s-video | x | |||||
| Composite video - example from ebay.com.au | composite | x |
** If the Automatic configuration value is 0 or 2, a load on R/G/B only is detected as component video, if the value is 1 or 3 it's detected as RGB.
Mini-DIN 8 pin RGB
This connector, along with a audio socket is supplied with all NESRGB kits. If using the supplied 8 pin mini-din connector it should be connected according to the following table. You have the choice of putting the audio through the mini DIN cable or using a separate connector. My cable set will accept audio either way, but note that there is not a shield between the audio and video wires inside the mini-din cable, so better results may be achieved by putting audio out through the separate cable. Retro Gaming Cables also sells a compatible SCART cable.| Min DIN pin nr. | Pin label | NESRGB solder pad | Description |
| 1 | R |
AO |
Audio right output |
| 2 | L |
AO |
Audio left output |
| 3 | V |
VS |
Video/sync (outputs sync only in RGB mode) |
| 4 | GND | GND | Ground |
| 5 | +5 | +5V | 5V power output for SCART switching signals |
| 6 | B | B | Blue video output |
| 7 | G | G | Green video output |
| 8 | R | R | Red video output |
| Shield (connected to pin 4) | GND | Ground | |
Neo Geo 8 pin DIN RGB connection
This is a good choice for Famicom Twin consoles as there is already a mounting place for an 8 pin DIN socket on the AV board. Neo Geo SCART cables are available from various places.
| DIN8 pin nr. | NESRGB solder pad | Description |
| 1 | AO | Audio output |
| 2 | GND | Ground |
| 3 | VS | Video/sync (outputs sync only in RGB mode) |
| 4 | +5V | 5V power output for SCART switching signals |
| 5 | G | Green video output |
| 6 | R | Red video output |
| 7 | CS# | TTL Sync (some cables use this instead of pin 3) |
| 8 | B | Blue video output |
| Shield | GND | Ground |
Advice against using Sega Master System or Mega Drive RGB cables
For some reason many customers try to use Mega Drive SCART cables with the NESRGB. This cable contains resistors in series with the R, G, B signals which makes it incompatible with anything but a Mega Drive console. Do not remove the 75 ohm series resistors from the video outputs of the NESRGB board to make it work. They are required for three reasons 1. Load detection 2. Short circuit and ESD protection 3. Isolation from cable capacitance which is about 250p on a shielded two metre long cable. If you absolutely must use a Sega Mega/Master RGB cable then remove the resistors from inside of it so it behaves like a normal cable. Cables which have internal video driver electronics (for example HD Retrovision cables) are OK to use because it does not load NESRGB video outputs.Controller wiring
In the lower right corner of the NESRGB board there is a row of pads that looks like the picture below.
| NESRGB solder pad | Description |
| RO | Reset output |
| 1D | Controller data |
| 2C | Controller clock |
| 3L | Controller latch |
These must be connected to appropriate points on the motherboard. See the installation guides for more details.
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Last updated 30/4/2026.