19 PIN D-SUB CONNECTOR
| Pin | Name | Description | 
|---|---|---|
| 1 | Ground | |
| 2 | Ground | |
| 3 | Ground | |
| 4 | Ground | |
| 5 | -12V | -12 VDC | 
| 6 | +5V | +5 VDC | 
| 7 | +12V | +12 VDC | 
| 8 | +12V | +12 VDC | 
| 9 | ? | ? | 
| 10 | PWM | Regulates speed of the drive | 
| 11 | PH0 | Control line to send commands to the drive | 
| 12 | PH1 | Control line to send commands to the drive | 
| 13 | PH2 | Control line to send commands to the drive | 
| 14 | PH3 | Control line to send commands to the drive | 
| 15 | WrReq- | Turns on the ability to write data to the drive | 
| 16 | HdSel | Control line to send commands to the drive | 
| 17 | Enbl2- | Enables the Rd line (else Rd is tri-stated) | 
| 18 | Rd | Data actually read from the drive | 
| 19 | Wr | Data actually written to the drive | 
Contributor: Joakim Ögren
  Source:
  Technote HW19: Pinouts at Apple Technical Notes
  Copyright © The Hardware Book Team 1996-2001.
  May be copied and redistributed, partially or in whole, as appropriate.
 Document last modified: 2000-07-09