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Table of Contents
Amiga Bus
Here is some data on the Amiga's bus. Since I'm gathering enough data to build a Zorro II card I figured I could consolidate it and share it.
- pin1 from the underside, where the pokeys poke through, is top right
- pin1 from the top where the card goes in is top left
Bus
This is a popular copy of the pin out of the Amiga Bus, The A2000 and A3000 use a 100pin edge connector. This is a standard connector. If you can find one for a PC (IBM clone) it will work in the Amiga.
Why no reference to A4000? I know everyone wants one, but, the A3000 was the peak for me. If you want to donate me an A4000 I'll write up notes for it.
| Pin | A500 | A1000 | A2000 | A2000B | Name | Description |
|---|---|---|---|---|---|---|
| 1 | X | X | X | X | GND | Ground |
| 2 | X | X | X | X | GND | Ground |
| 3 | X | X | X | X | GND | Ground |
| 4 | X | X | X | X | GND | Ground |
| 5 | X | X | X | X | +5V | +5 Volts DC |
| 6 | X | X | X | X | +5V | +5 Volts DC |
| 7 | X | X | X | X | n/c | |
| 8 | X | X | X | X | -5V | -5 Volts DC |
| 9 | X | X | n/c | |||
| 9 | X | X | 28CLOCK | 28MHz Clock | ||
| 10 | X | X | X | X | +12V | +12 Volts DC |
| 11 | X | X | n/c | |||
| 11 | X | X | /COPCFG | Configuration Out | ||
| 12 | X | X | X | X | CONFIG IN | Grounded |
| 13 | X | X | X | X | GND | Ground |
| 14 | X | X | X | X | /C3 | C3 Clock |
| 15 | X | X | X | X | CDAC | Clock |
| 16 | X | X | X | X | /C1 | C1 Clock |
| 17 | X | X | X | X | /OVR | |
| 18 | X | X | X | X | RDY | Ready |
| 19 | X | X | X | X | /INT2 | Interrupt 2 |
| 20 | X* | X | /PALOPE | * This signal is NC on a A500 with a Gary Chip | ||
| 20 | X | n/c | ||||
| 20 | X | /BOSS | ||||
| 21 | X | X | X | X | A5 | Address 5 |
| 22 | X | X | X | X | /INT6 | Interrupt 6 |
| 23 | X | X | X | X | A6 | Address 6 |
| 24 | X | X | X | X | A4 | Address 4 |
| 25 | X | X | X | X | GND | Ground |
| 26 | X | X | X | X | A3 | Address 3 |
| 27 | X | X | X | X | A2 | Address 2 |
| 28 | X | X | X | X | A7 | Address 7 |
| 29 | X | X | X | X | A1 | Address 1 |
| 30 | X | X | X | X | A8 | Address 8 |
| 31 | X | X | X | X | FC0 | Processor status 0 |
| 32 | X | X | X | X | A9 | Address 9 |
| 33 | X | X | X | X | FC1 | Processor status 1 |
| 34 | X | X | X | X | A10 | Address 10 |
| 35 | X | X | X | X | FC2 | Processor status 2 |
| 36 | X | X | X | X | A11 | Address 11 |
| 37 | X | X | X | X | GND | Ground |
| 38 | X | X | X | X | A12 | Address 12 |
| 39 | X | X | X | X | A13 | Address 13 |
| 40 | X | X | X | X | /IPL0 | |
| 41 | X | X | X | X | A14 | Address 14 |
| 42 | X | X | X | X | /IPL1 | |
| 43 | X | X | X | X | A15 | Address 15 |
| 44 | X | X | X | X | /IPL2 | |
| 45 | X | X | X | X | A16 | Address 16 |
| 46 | X | X | X | X | /BEER | Bus Error |
| 47 | X | X | X | X | A17 | Address |
| 48 | X | X | X | X | /VPA | |
| 49 | X | X | X | X | GND | Ground |
| 50 | X | X | X | X | ECLK | E Clock |
| 51 | X | X | X | X | /VMA | |
| 52 | X | X | X | X | A18 | Address 18 |
| 53 | X | X | X | X | RST | Reset |
| 54 | X | X | X | X | A19 | Address 19 |
| 55 | X | X | X | X | /HLT | Halt |
| 56 | X | X | X | X | A20 | Address 20 |
| 57 | X | X | X | X | A22 | Address 22 |
| 58 | X | X | X | X | A21 | Address 21 |
| 59 | X | X | X | X | A23 | Address 23 |
| 60 | X | X | /BR | |||
| 60 | X | X | /CBR | |||
| 61 | X | X | X | X | GND | Ground |
| 62 | X | X | X | X | /BGACK | |
| 63 | X | X | X | X | D15 | Data 15 |
| 64 | X | X | /BG | |||
| 64 | X | X | /CBG | |||
| 65 | X | X | X | X | D14 | Data 14 |
| 66 | X | X | X | X | /DTACK | |
| 67 | X | X | X | X | D13 | Data 13 |
| 68 | X | X | X | X | R/W | Read/Write |
| 69 | X | X | X | X | D12 | Data 12 |
| 70 | X | X | X | X | /LDS | |
| 71 | X | X | X | X | D11 | Data 11 |
| 72 | X | X | X | X | /UDS | |
| 73 | X | X | X | X | GND | Ground |
| 74 | X | X | X | X | /AS | |
| 75 | X | X | X | X | D0 | Data 0 |
| 76 | X | X | X | X | D10 | Data 10 |
| 77 | X | X | X | X | D1 | Data 1 |
| 78 | X | X | X | X | D9 | Data 9 |
| 79 | X | X | X | X | D2 | Data 2 |
| 80 | X | X | X | X | D8 | Data 8 |
| 81 | X | X | X | X | D3 | Data 3 |
| 82 | X | X | X | X | D7 | Data 7 |
| 83 | X | X | X | X | D4 | Data 4 |
| 84 | X | X | X | X | D6 | Data 6 |
| 85 | X | X | X | X | GND | Ground |
| 86 | X | X | X | X | D5 | Data 5 |
Memory Map
This is a grab of some data found on the Interwebs. This shows both Zorro II and III details
| Address | Size [MByte] | Description |
|---|---|---|
| 0x0000 0000 | 2.0 | Chip memory |
| 0x0020 0000 | 8.0 | Zorro II memory expansion space |
| 0x00A0 0000 | 1.5 | Zorro II I/O expansion space |
| 0x00B8 0000 | 3.0 | A2000 motherboard register space |
| 0x00E8 0000 | 0.5 | Zorro II I/O |
| 0x00F0 0000 | 1.0 | Motherboard ROM |
| 0x0100 0000 | 112.0 | A3000 motherboard space |
| 0x0800 0000 | 128.0 | 32-Bit memory expansion space |
| 0x1000 0000 | 1792.0 | Zorro III expansion space |
| 0x8000 0000 | 2032.0 | Reserved |
| 0xFF00 0000 | 64 KB | Zorro III Configuration unit |
| 0xFF01 0000 | 16.0 | Reserved |
| 0xFFFF FFFF | 16.0 | Reserved |
| Who can count hexadecimal? is 0xFF01 0000 to 0xFFFF FFFF equal to 16MB? I'm not clear if the last fields are a beginning and end range or two ranges each at 16MB |
Power
This appears to the power that can be drawn through the bus. Nowadays, the only thing people care about is the 5v.
| Volt | Ampere |
|---|---|
| +5 | 2.0 |
| -5 | < 0.3 |
| +12 | < 8.0 |
| -12 | < 0.3 |