MOS Technology Agnus

The MOS Technology "Agnus", usually called Agnus is an integrated circuit in the custom chipset of the Commodore Amiga computer. The Agnus, Denise and Paula chips collectively formed the OCS and ECS chipsets.

The Agnus is the Address Generator Chip. Its main function, in chip area, is the RAM Address Generator and Register Address Encoder which handles all DMA addresses. The 8361 Agnus is made up of approximately 21000 transistors and contains DMA Channel Controllers. According to Jay Miner, original Agnus was fabricated in 5 µm manufacturing process like all OCS chipset. The Blitter and Copper are also contained here.

Agnus features:

Agnus was replaced by Alice in the Amiga 4000 and Amiga 1200 when the AGA chipset was introduced in 1992.

* Somewhere 8372A Agnus mentioned as simply "8372".

Notes
Fat Agnus 1MB and Fat Agnus 2MB usually known as Super Agnus; Super Fat Agnus; Fatter Agnus; Big Agnus; Big Fat Agnus, but these aren't official names.

When swapping/upgrading chips pinouts need to be taken care of. Types are just mentioned for reference, four-digit types and pinouts/usage are not consistent.

References: A500 Service Training, A3000 Service Manual, A500+ Service Manual, A1200 schematics

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