RGB port

 RGB/Monitor port connections.

Introduction

The RGB (Red, Green Blue) port is used to connect a monitor to your Amiga. It supports Analogue and digital monitors and the ability to add a genlock.

I provide a short overview of the operation of this port.

Connectors for the RGB port.

 

Type

Pin

Signal

Description

Input

1

XCLK

External clock frequency

Input

2

XCLKEN

Switch for external clock (47 Ohm)

Output

3

R

Analogue Red Signal (75 Ohm)

Output

4

G

Analogue Green Signal (75 Ohm)

Output

5

B

Analogue Blue Signal (75 Ohm)

Output

6

DI

Digital Brightness signal (75 Ohm)

Output

7

DB

Digital Blue signal (47 Ohm)

Output

8

DG

Digital Green signal (47 Ohm)

Output

9

Dr

Digital Red signal (47 Ohm)

Output

10

QCSY

Buffered composite sync signal (47 Ohm)

In/Out

11

HSY

Horizontal synchronization (47 Ohm)

In/Out

12

VSY

Vertical synchronisation (47 Ohm)

 

13

GND

Ground for XCLK or XLCKEN only

OUTPUT

14

ZD

Zero detect (genlock overlay) 47 Ohm

OUTPUT

15

C1U

Amiga C1u timer (3.58 MHz)

 

16

GND

 

 

17

GND

 

 

18

GND

 

 

19

GND

 

 

20

GND

 

 

21

-5 Volts

10 mA max, A1000, A2000, A3000 & A4000

 

 

-12 Volts

10 mA max, A500, A600 & A1200

 

22

+12 Volts

100 mA max.

 

23

+5 Volts

100 mA max.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 Can I use a SVGA monitor with my Amiga?

Yes and no.

The default scanning video scanning frequency of the Amiga  is around 15 KHz, which is fine for TVs as PAL is 15.625 KHz Vertical and 50 Hz horizontal and NTSC is 15.750 KHz.vertical and 60 Hz horizontal.

VGA monitors use a 31.25 KHz Vertical scanning rate. The Amiga's, by default is only half this frequency. So if the vertical scanning rate is doubled, it will be compatible with a VGA monitor.

If you own an A3000, you are lucky as it included a built in scan doubler and flicker fixer. Other Amiga user's need to purchase a scandoubler which cost between 50 and 80. I recommend one with a flicker fixer.

 I don't want to use a Scandoubler?

Well starting with the Enhnaced chipset (ECS) provision was made to allow the chipset to work in 31 KHz modes and allow the use of a VGA monitor. Whilst this works adequately, if you only use  a VGA monitor, you will not be able to see any Amiga native (15 KHz) modes.

There are some hacks on Aminet, but I have not tried any of them.

 By Ian Stedman, 13th November 2001

Updated 08 July 2017