RGB21 connector
This page was last modified 08:19, 12 October 2023 by Mars2000you. Based on work by Gdx and Sdsnatcher73 and others.



The RGB21 connector (called also RGB Multi) is the same connector that is used for SCART, but the pinout has a different meaning.

Specifications are also more or less different. This connector is a standard established by EIAJ (EIAJ CPR-1201).

Note: A similar pinout can be found on the 25-pin D-Sub Victor HC-90/HC-95 RGB Connector, but there are differences:

  • there are 4 extra non-connected pins, whose utility is unknown
  • the HC-9X doesn't have C-Sync & YS inputs nor video out, and RGB21 doesn't seem to have the same SYNC OUT

Pinout (RGB and Composite Video)

RGB21 connector

Pin Description Signal level Impedance
1 Audio left/mono channel input 0.4V (rms) 47 kΩ
2 Audio left/mono channel output 0.4V (rms) 10 kΩ
3 Audio channel inputs ground
4 Audio channel outputs ground
5 Audio right channel input (N.C. on MSX) 0.4V (rms) 47 kΩ
6 Audio right channel output (N.C. on MSX) 0.4V (rms) 10 kΩ
7 C-Sync input ground
8 C-Sync output ground
9 C-Sync (Composite Video) input 1V (p-p) 75 Ω
10 C-Sync (Composite Video) output 1V (p-p) 75 Ω
11 AV control input 3 ~ 5V 22k Ω
12 YM input (RGB video mask) 1 ~ 3V 75 Ω
13 Red signal ground
14 YM & YS ground
15 Red signal (I/O) 0.7 V (p-p) 75 Ω
16 YS input 0 ~ 0.4V = Composite mode
1.0 ~ 3.0V = RVB mode
75 Ω
17 Green signal ground
18 Blue signal ground
19 Green signal (I/O) 0.7 V (p-p) 75 Ω
20 Blue signal (I/O) 0.7 V (p-p) 75 Ω
21 Plug shield

List of MSX hardware with RGB21 connector


Model Generation
National CF-3000 MSX1
National CF-3300 MSX1
National FS-4000 MSX1
National FS-4500 MSX2
National FS-4700 MSX2
National FS-5000F2 MSX2
National FS-5500F1 MSX2
National FS-5500F2 MSX2
Sanyo MPC-11 MSX1
Sanyo MPC-25F MSX2
Sanyo MPC-25FD MSX2
Sanyo MPC-25FK MSX2
Sanyo MPC-25FS MSX2
Sanyo MPC-27 MSX2
Sanyo PHC-50FD2 MSX2
Sony HB-701 MSX1
Sony HB-701FD MSX1
Sony HB-F5 MSX2
Sony HB-F500 MSX2
Sony HB-F750 MSX2
Victor HC-7 MSX1
Victor HC-80 MSX2


Other devices

How to make a RGB21 to SCART cable

Connect the wires as follows:

RGB21 Signal SCART
15 Red signal 15
19 Green signal 11
20 Blue signal 7
10 Sync/Video 20
2 Audio left 6
6 Audio right 2
11 +5V (or better +12V) 8
7, 3, 21, 13, 18 and 17 Corresponding grounds 5, 9, 18, 13, 14 and 17
21 Plug shield 21

It is often necessary to add the following components:

  • A 100~220μF polarized capacitor on each RGB pin of the scart. (Three same capacitors, the + connected on the wire that go to the RGB21 connector)
  • A 100 Ω resistor between the pin 8 of RGB21 and the pin 16 of the SCART.