Difference between revisions of "Agnus"

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=== History ===
 
=== History ===
  
The heart of the Amiga, Agnus was designed by [[Jay Miner]], [[Joe Decuir]], [[Ron Nicholson]], [[Edwin Chu]] and [[Dave Needle]]. The chip’s architecture remained relatively unchanged throughout development aside from the ability to address 512K of RAM and the addition of a line draw circuit, which was suggested by [[DaleLuck|Dale Luck]].
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[[File:A8361r3.jpeg|thumb|right|Agnus 8361 R3 from an NTSC A1000]]
 +
 
 +
The heart of the Amiga, Agnus was designed by [[Jay Miner]], [[Joe Decuir]], [[Ron Nicholson]], [[Edwin Chu]] and [[Dave Needle]]. The chip’s line draw feature was suggested by [[DaleLuck|Dale Luck]] and implemented by [[Dave Needle]] shortly before the 1984 Winter CES in Las Vegas, where the [[Lorraine]] was first shown.
  
 
Early versions of the chip are also known as 4701.
 
Early versions of the chip are also known as 4701.
Line 7: Line 9:
 
=== Specifications ===
 
=== Specifications ===
  
Agnus provides a memory controller, address generator and video sync signals.
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Agnus provides a DMA controller, address generator and video sync signals. 25 DMA channels are control functions for memory refresh, blitter, bitplanes, "Copper" co-processor, sprites, audio and disk drive. The address generator provides a bus which all three custom chips share, the Register Address Bus. Horizonal, vertical and composite sync signals are available and can be used for an RGB monitor, genlock, composite video or TOD clocks for the two CIA chips.
 +
 
 +
=== Versions ===
 +
 
 +
[[Agnus (wire wrap)]]<br>
 +
 
 +
{| class="wikitable"
 +
|-
 +
! Model No. !! Region !! Hardware
 +
|-
 +
| 4701 || NTSC || ICS
 +
|-
 +
| 8361 || NTSC || OCS
 +
|-
 +
| 8367 || PAL || OCS
 +
|-
 +
| 8370 || NTSC || ECS
 +
|-
 +
| 8371 || PAL || ECS
 +
|-
 +
| 8372 || PAL || ECS
 +
|-
 +
| 8372A || PAL || ECS
 +
|-
 +
| 8372AB || PAL || ECS
 +
|-
 +
| 8372B || NTSC || ECS
 +
|-
 +
| 8375 || NTSC || ECS
 +
|-
 +
| 8375 || PAL || ECS
 +
|}
 +
 
 +
=== Pinout (OCS versions) ===
 +
 
 +
'''1''' D8<br>
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'''2''' D7<br>
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'''3''' D6<br>
 +
'''4''' D5<br>
 +
'''5''' D4<br>
 +
'''6''' D3<br>
 +
'''7''' D2<br>
 +
'''8''' D1<br>
 +
'''9''' D0<br>
 +
'''10''' VCC<br>
 +
'''11''' /RES<br>
 +
'''12''' /INT3<br>
 +
'''13''' DMAL<br>
 +
'''14''' /BLS<br>
 +
'''15''' /DBR<br>
 +
'''16''' /ARW<br>
 +
'''17''' RGA8<br>
 +
'''18''' RGA7<br>
 +
'''19''' RGA6<br>
 +
'''20''' RGA5<br>
 +
'''21''' RGA4<br>
 +
'''22''' RGA3<br>
 +
'''23''' RGA2<br>
 +
'''24''' RGA1<br>
 +
'''25''' CCK<br>
 +
'''26''' CCKQ<br>
 +
'''27''' VSS<br>
 +
'''28''' DRA0<br>
 +
'''29''' DRA1<br>
 +
'''30''' DRA2<br>
 +
'''31''' DRA3<br>
 +
'''32''' DRA4<br>
 +
'''33''' DRA5<br>
 +
'''34''' DRA6<br>
 +
'''35''' DRA7<br>
 +
'''36''' DRA8<br>
 +
'''37'''  /LP<br>
 +
'''38''' /VSY<br>
 +
'''39''' /CSY<br>
 +
'''40''' /HSY<br>
 +
'''41''' VSS<br>
 +
'''42''' D15<br>
 +
'''43''' D14<br>
 +
'''44''' D13<br>
 +
'''45''' D12<br>
 +
'''46''' D11<br>
 +
'''47''' D10<br>
 +
'''48''' D9<br>
  
=== Pinout ===
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== References ==
  
1 D8
+
# Peck, Rob. ''Amiga Hardware Manual'' 1985
2 D7
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# ''[https://bigbookofamigahardware.com/bboah/product.aspx?id=1478 Agnus]'' Big Book of Amiga Hardware
3 D6
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# Caufield, Nicola and Anthony, directors. ''[https://rebellion.vhx.tv/products From Bedrooms to Billions: The Amiga Years]''. Rebellion, 2015
4 D5
 
5 D4
 
6 D3
 
7 D2
 
8 D1
 
9 D0
 
10 VCC
 
11 /RES
 
12 /INT3
 
13 DMAL
 
14 /BLS
 
15 /DBR
 
16 /ARW
 
17 RGA8
 
18 RGA7
 
19 RGA6
 
20 RGA5
 
21 RGA4
 
22 RGA3
 
23 RGA2
 
24 RGA1
 
25 CCK
 
26 CCKQ
 
27 VSS
 
28 DRA0
 
29 DRA1
 
30 DRA2
 
31 DRA3
 
32 DRA4
 
33 DRA5
 
34 DRA6
 
35 DRA7
 
36 DRA8
 
37  /LP
 
38 /VSY
 
39 /CSY
 
40 /HSY
 
41 VSS
 
42 D15
 
43 D14
 
44 D13
 
45 D12
 
46 D11
 
47 D10
 
48 D9
 

Latest revision as of 22:11, 23 June 2023

History

Agnus 8361 R3 from an NTSC A1000

The heart of the Amiga, Agnus was designed by Jay Miner, Joe Decuir, Ron Nicholson, Edwin Chu and Dave Needle. The chip’s line draw feature was suggested by Dale Luck and implemented by Dave Needle shortly before the 1984 Winter CES in Las Vegas, where the Lorraine was first shown.

Early versions of the chip are also known as 4701.

Specifications

Agnus provides a DMA controller, address generator and video sync signals. 25 DMA channels are control functions for memory refresh, blitter, bitplanes, "Copper" co-processor, sprites, audio and disk drive. The address generator provides a bus which all three custom chips share, the Register Address Bus. Horizonal, vertical and composite sync signals are available and can be used for an RGB monitor, genlock, composite video or TOD clocks for the two CIA chips.

Versions

Agnus (wire wrap)

Model No. Region Hardware
4701 NTSC ICS
8361 NTSC OCS
8367 PAL OCS
8370 NTSC ECS
8371 PAL ECS
8372 PAL ECS
8372A PAL ECS
8372AB PAL ECS
8372B NTSC ECS
8375 NTSC ECS
8375 PAL ECS

Pinout (OCS versions)

1 D8
2 D7
3 D6
4 D5
5 D4
6 D3
7 D2
8 D1
9 D0
10 VCC
11 /RES
12 /INT3
13 DMAL
14 /BLS
15 /DBR
16 /ARW
17 RGA8
18 RGA7
19 RGA6
20 RGA5
21 RGA4
22 RGA3
23 RGA2
24 RGA1
25 CCK
26 CCKQ
27 VSS
28 DRA0
29 DRA1
30 DRA2
31 DRA3
32 DRA4
33 DRA5
34 DRA6
35 DRA7
36 DRA8
37 /LP
38 /VSY
39 /CSY
40 /HSY
41 VSS
42 D15
43 D14
44 D13
45 D12
46 D11
47 D10
48 D9

References

  1. Peck, Rob. Amiga Hardware Manual 1985
  2. Agnus Big Book of Amiga Hardware
  3. Caufield, Nicola and Anthony, directors. From Bedrooms to Billions: The Amiga Years. Rebellion, 2015