To provide better signal integrity, the 80 wire cable is mandatory for systems using DMA/66 mode. Every even wire is connected to the ground pins in each connector. Used connectors are same as in 40 wire cable.
| Pin | Description | Pin | Description |
|---|---|---|---|
| 1 | -RESET | 2 | GND |
| 3 | Data bit 7 | 4 | Data bit 8 |
| 5 | Data bit 6 | 6 | Data bit 9 |
| 7 | Data bit 5 | 8 | Data bit 10 |
| 9 | Data bit 4 | 10 | Data bit 11 |
| 11 | Data bit 3 | 12 | Data bit 12 |
| 13 | Data bit 2 | 14 | Data bit 13 |
| 15 | Data bit 1 | 16 | Data bit 14 |
| 17 | Data bit 0 | 18 | Data bit 15 |
| 19 | GND | 20 | (key pin, missing) |
| 21 | DRQ 3 | 22 | GND |
| 23 | -IOW | 24 | GND |
| 25 | -IOR | 26 | GND |
| 27 | IOCHRDY | 28 | SPSYNC:CSEL |
| 29 | -DACK 3 | 30 | GND |
| 31 | IRQ 14/15 | 32 | -IOCS16 |
| 33 | Addr bit 1 | 34 | -PDIAG |
| 35 | Addr bit 0 | 36 | Addr bit 2 |
| 37 | -CS1FX | 38 | -CS3FX |
| 39 | -DA/SP | 40 | GND |
| Pin | Description | Pin | Description |
|---|---|---|---|
| A | Option selection pin | B | Option selection pin |
| C | Option selection pin | D | Option selection pin |
| E | (key pin, missing) | F | (key pin, missing) |
| 1 ... 40 | Same as the 40pin connector | ||
| 41 | +5V (logic) | 42 | +5V (motor) |
| 43 | GND | 44 | -TYPE (0=ATA) |