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ECS Chipset Memory Amiga OS A3000 A3000T A3000UX A500+ A600

The Amiga's Custom Chips - ECS

The Enhanced Chip Set (ECS) was used for all of the third generation machines, i.e the A3000, A3000T, A3000UX, A500+ and A600. It consisted of three main chips, Paula, Agnus and Denise although the Agnus chip underwent a number of upgrades of its life, and the graphics potential available from the Amiga depends on which chip has been fitted.

Agnus The custom chip used to control and move data to be displayed on the screen for all Amigas except the A1200 and A4000. It is also responsible for timing the machine and even directs animation. Agnus has been upgraded a number of times, and the capabilites of the one installed in your machine dictates just what characteristics your machine has.
  • Super Fat Agnus (8372B) 2Mb Chip RAM, Productivity & super hires modes
  • Obese Agnus (8373) 2Mb Chip RAM
Denise The custom chip that is responsible for the video output and is used to maintain the screen display on Amiga models running the chipset. It controls the resolution, colours, sprites, text lines, etc. On the A1200 and A4000 machines it has been superceded by the LISA chip to perform the same functions and more. Where the AAA chipset has been fitted these chips have been superceded by the MONICA chip.
Paula The custom chip responsible for all of the sounds generated from the Amiga. It provides four voices of sound output configured as two stereo channels with nine octaves over a range of complex waveforms, and uses both amplitude and frequency modulation. It also handles many of the input/ output tasks such as disk and interrupt control, the mouse, joystick and serial ports. This chip has been superceded by Mary in the AAA chipset.

Copyright 2005 Amiga Auckland Inc. All rights reserved.
Revised: September 25, 2005.