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 02 May 2011