![Commodore Amiga 1000 - main board - MOS 8367R0-7824](https://upload.wikimedia.org/wikipedia/commons/0/0e/Commodore_Amiga_1000_-_main_board_-_MOS_8367R0-7824.jpg)
The
MOS Technology
MOS Technology, Inc. ("MOS" being short for Metal Oxide Semiconductor), later known as CSG (Commodore Semiconductor Group) and GMT Microelectronics, was a semiconductor design and fabrication company based in Audubon, Pennsylvania. It is mo ...
"Agnus", usually called Agnus, is an
integrated circuit
An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, usually silicon. Large numbers of tiny ...
in the custom
chipset
In a computer system, a chipset is a set of electronic components
An electronic component is any basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields. Electronic components are ...
of the
Amiga
Amiga is a family of personal computers introduced by Commodore in 1985. The original model is one of a number of mid-1980s computers with 16- or 32-bit processors, 256 KB or more of RAM, mouse-based GUIs, and significantly improved graphi ...
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
Ram, ram, or RAM may refer to:
Animals
* A male sheep
* Ram cichlid, a freshwater tropical fish
People
* Ram (given name)
* Ram (surname)
* Ram (director) (Ramsubramaniam), an Indian Tamil film director
* RAM (musician) (born 1974), Dutch
* ...
Address Generator and Register Address Encoder which handles all
DMA addresses. The 8361 Agnus is made up of approximately 21000
transistor
upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch e ...
s and contains DMA Channel Controllers. According to
Jay Miner
Jay Glenn Miner (May 31, 1932 – June 20, 1994) was an American integrated circuit designer, known primarily for developing graphics and audio chips for the Atari 2600 and Atari 8-bit family and as the "father of the Amiga".
Early life
Jay ...
, original Agnus was fabricated in 5 μm manufacturing process like all
OCS chipset. The
Blitter
A blitter is a circuit, sometimes as a coprocessor or a logic block on a microprocessor, dedicated to the rapid movement and modification of data within a computer's memory. A blitter can copy large quantities of data from one memory area to anot ...
and
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
are also contained here.
Agnus features:
* The
Blitter
A blitter is a circuit, sometimes as a coprocessor or a logic block on a microprocessor, dedicated to the rapid movement and modification of data within a computer's memory. A blitter can copy large quantities of data from one memory area to anot ...
, a
bitmap
In computing, a bitmap is a mapping from some domain (for example, a range of integers) to bits. It is also called a bit array
A bit array (also known as bitmask, bit map, bit set, bit string, or bit vector) is an array data structure that c ...
manipulator. The Blitter is capable of copying blocks of display data, or any arbitrary data in the on-board memory, at high speed with various raster operations as well as drawing pixel perfect lines and filling outlined polygons, while freeing the CPU for concurrent tasks.
* "
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
", a display synchronized co-processor
* 25
Direct Memory Access
Direct memory access (DMA) is a feature of computer systems and allows certain hardware subsystems to access main system memory independently of the central processing unit (CPU).
Without DMA, when the CPU is using programmed input/output, it is t ...
(DMA) channels, allowing graphics, sound and I/O to be used with minimal CPU intervention
*
DRAM
Dynamic random-access memory (dynamic RAM or DRAM) is a type of random-access semiconductor memory that stores each bit of data in a memory cell, usually consisting of a tiny capacitor and a transistor, both typically based on metal-oxid ...
refresh controller
* Memory controller (memory that can be accessed by the processor and the chipset)
* Generates the system clock from the 28 MHz oscillator
* Video timing
Agnus was replaced by
Alice in the
Amiga 4000
The Commodore Amiga 4000, or A4000, is the successor of the A2000 and A3000 computers. There are two models: the A4000/040 released in October 1992 with a Motorola 68040 CPU, and the A4000/030 released in April 1993 with a Motorola 68EC030. ...
and
Amiga 1200
The Amiga 1200, or A1200 (code-named " Channel Z"), is a personal computer in the Amiga computer family released by Commodore International, aimed at the home computer market. It was launched on October 21, 1992, at a base price of £399 in the ...
when the
AGA
Aga or AGA may refer to:
Business
* Architectural Glass and Aluminum (AGA), a glazing contractor, established in 1970
* AGA (automobile), ''Autogen Gasaccumulator AG'', 1920s German car company
*AGA AB, ''Aktiebolaget Svenska Gasaccumulator'', a ...
chipset was introduced in 1992.
Chips by capability
![CBM 8370R3 top metal](https://upload.wikimedia.org/wikipedia/commons/9/9f/CBM_8370R3_top_metal.jpg)
*
OCS Agnus which can address up to 512 kB of
Chip RAM Chip RAM is a commonly used term for the integrated RAM used in Commodore's line of Amiga computers. Chip RAM is shared between the central processing unit (CPU) and the Amiga's dedicated chipset (hence the name). It was also, rather misleadingly, ...
(PLCC versions add 512 kB of pseudo-fast RAM)
** 8361 (
DIP) -
Amiga 1000
The Commodore Amiga 1000, also known as the A1000, is the first personal computer released by Commodore International in the Amiga line. It combines the 16/32-bit Motorola 68000 CPU which was powerful by 1985 standards with one of the most adv ...
(NTSC);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model A (NTSC)
** 8367 (DIP) -
Amiga 1000
The Commodore Amiga 1000, also known as the A1000, is the first personal computer released by Commodore International in the Amiga line. It combines the 16/32-bit Motorola 68000 CPU which was powerful by 1985 standards with one of the most adv ...
(PAL);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model A (PAL)
** 8370 (
PLCC) -
Amiga 500
The Amiga 500, also known as the A500, is the first low-end version of the Amiga home computer. It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that ...
to Rev 5.x (NTSC);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model B to Rev 4.5 (NTSC)
** 8371 (
PLCC) -
Amiga 500
The Amiga 500, also known as the A500, is the first low-end version of the Amiga home computer. It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that ...
to Rev 5.x (PAL);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model B to Rev 4.5 (PAL)
*
ECS Agnus which can address up to 1 MB of
Chip RAM Chip RAM is a commonly used term for the integrated RAM used in Commodore's line of Amiga computers. Chip RAM is shared between the central processing unit (CPU) and the Amiga's dedicated chipset (hence the name). It was also, rather misleadingly, ...
** 8372 - no data
*
** 8372A -
Amiga 500
The Amiga 500, also known as the A500, is the first low-end version of the Amiga home computer. It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that ...
from Rev 6 (NTSC/PAL);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model B from Rev 6.0 to Rev 6.3 (NTSC/PAL);
Commodore CDTV
The CDTV (from Commodore Dynamic Total Vision, later treated as a backronym for Compact Disc Television) is a home multimedia entertainment and video game console – convertible into a full-fledged personal computer by the addition of optional ...
** 8375 (318069-16 only) (PAL) -
Amiga 500
The Amiga 500, also known as the A500, is the first low-end version of the Amiga home computer. It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that ...
from Rev 6 (PAL);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model B from Rev 6.4 (PAL)
** 8375 (318069-17 only) (NTSC) -
Amiga 500
The Amiga 500, also known as the A500, is the first low-end version of the Amiga home computer. It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that ...
from Rev 6 (NTSC);
Amiga 2000
The Amiga 2000, or A2000, is a personal computer released by Commodore in March 1987. It was introduced as a "big box" expandable variant of the Amiga 1000 but quickly redesigned to share most of its electronic components with the contemporary Ami ...
model B from Rev 6.4 (NTSC)
*
ECS Agnus which can address up to 2 MB of
Chip RAM Chip RAM is a commonly used term for the integrated RAM used in Commodore's line of Amiga computers. Chip RAM is shared between the central processing unit (CPU) and the Amiga's dedicated chipset (hence the name). It was also, rather misleadingly, ...
** 8372AB -
Amiga 3000 from Rev 6.1 to Rev 8.9 (NTSC/PAL)
** 8372B -
Amiga 3000 Rev 9 (NTSC/PAL)
** 8375 (PAL) -
Amiga 500 Plus
The Amiga 500, also known as the A500, is the first low-end version of the Amiga home computer. It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that ...
;
Amiga 600 (PAL)
** 8375 (NTSC) -
Amiga 600 (NTSC)
* Somewhere 8372A Agnus mentioned as simply "8372".
Chips by package
* 48-lead
DIP Agnus (aka thin Agnus): 8361; 8367
* 84-contact
PLCC Fat Agnus (named Fat Lady on most Amiga 2000 motherboards) 8370; 8371; 8372; 8372A; 8372AB; 8372B; 8375
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.
DMA Channels
Pinout
PLCC Versions
When replacing or 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
See also
References
;Sources
* AMIGA 1000 ASSEMBLY LEVEL REPAIR (Commodore-Amiga, Inc.) 1985 PN 314038-0
Dave's Amiga Schematics and Manuals* Commodore Amiga A500/A2000 Technical Reference Manual (Commodore-Amiga, Inc.) 198
* A500 SYSTEM SCHEMATICS COMPONENT PART LIST (Rev 6A/7
* A3000 SYSTEM SCHEMATICS (Commodore Business Machines, Inc.) March, 1990 PN-314677-0
www.1000bit.net* CDTV SERVICE MANUAL (Commodore International Spare GmbH) May, 1991 PN-400403-0
www.ianstedman.co.uk (ZIP-file)* A500 PLUS SERVICE MANUAL (Commodore International Spare GmbH) October, 1991 PN-400420-0
www.1000bit.net* A600 SYSTEM SCHEMATICS (Commodore International Spare GmbH) April, 1992 PN-400422-0
www.1000bit.netOBLIGEMENT: les chipsets de l'AmigaBig Book of Amiga Hardware* alexh o
(Agnus 8372B info)
* National Amiga Inc.''
mirrored on l8r.netMarketed Commodore Amiga models;Notes
{{DEFAULTSORT:Mos Technology Agnus
MOS Technology integrated circuits
Amiga