IDE Internal Connector Pinout
From AllPinouts
Connector pinout for: IDE Internal
IDE = Integrated Drive Electronics
Developed by Compaq and Western Digital.
Newer version of IDE goes under the name ATA=AT bus Attachment.
Often, the control circuitry is built into the motherboard, eliminating the requirement for a separate Host Adapter.
There are 2 types of IDE interfaces...those for the 8-bit XT bus, and those for the 16-bit AT bus (detailed here).
The cable for IDE contains 40 conductors and has no twists.
Like an SCSI cable, the IDE cable uses a Dual-row Pin connector for both ends.
A single cable may be used to connect two drives, or two cables may be Daisy-Chained.
Most IDE Host Adapters will support two hard drives.
The first drive should be jumpered as the Master drive, and the second as the Slave drive.
Plug-in IDE Host Adapters are often called Paddle-Boards, and may contain a floppy controller, and serial and parallel ports.
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40 PIN IDC MALE at the controller and peripherals
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40 PIN IDC FEMALE at the cable
| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | /RESET | OUT | Reset |
| 2 | GND | - | Ground |
| 3 | DD7 | IN/OUT | Data 7 |
| 4 | DD8 | IN/OUT | Data 8 |
| 5 | DD6 | IN/OUT | Data 6 |
| 6 | DD9 | IN/OUT | Data 9 |
| 7 | DD5 | IN/OUT | Data 5 |
| 8 | DD10 | IN/OUT | Data 10 |
| 9 | DD4 | IN/OUT | Data 4 |
| 10 | DD11 | IN/OUT | Data 11 |
| 11 | DD3 | IN/OUT | Data 3 |
| 12 | DD12 | IN/OUT | Data 12 |
| 13 | DD2 | IN/OUT | Data 2 |
| 14 | DD13 | IN/OUT | Data 13 |
| 15 | DD1 | IN/OUT | Data 1 |
| 16 | DD14 | IN/OUT | Data 14 |
| 17 | DD0 | IN/OUT | Data 0 |
| 18 | DD15 | IN/OUT | Data 15 |
| 19 | GND | - | Ground |
| 20 | KEY | - | Key |
| 21 | n/c | - | Not connected |
| 22 | GND | - | Ground |
| 23 | /IOW | OUT | Write Strobe |
| 24 | GND | - | Ground |
| 25 | /IOR | OUT | Read Strobe |
| 26 | GND | - | Ground |
| 27 | IO_CH_RDY | IN | |
| 28 | ALE | OUT | Address Latch Enable |
| 29 | n/c | - | Not connected |
| 30 | GND | - | Ground |
| 31 | IRQR | IN | Interrupt Request |
| 32 | /IOCS16 | ? | IO ChipSelect 16 |
| 33 | DA1 | OUT | Address 1 |
| 34 | n/c | - | Not connected |
| 35 | DA0 | OUT | Address 0 |
| 36 | DA2 | OUT | Address 2 |
| 37 | /IDE_CS0 | OUT | (1F0-1F7) |
| 38 | /IDE_CS1 | OUT | (3F6-3F7) |
| 39 | /ACTIVE | OUT | Led driver |
| 40 | GND | - | Ground |
Notes
- Direction is Controller relative Devices (Harddisks)
References
- Wikipedia article "Advanced Technology Attachment"
- Overview and History of the IDE/ATA Interface
- ATA/ATAPI history
- Enhanced IDE/Fast-ATA/ATA-2 FAQ
- Hard Drive Size Barriers
- T13 Technical Standards Group
