The 34-pin IDC floppy disk interface supports up to two drives via a cable twist. Used in PCs from the 1980s through early 2000s.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | GND | Ground | GND |
| 8 | INDEX | Index signal spindle sync | I/O |
| 10 | MOTOR ENABLE A | Motor enable drive A | I/O |
| 14 | DRIVE SELECT A | Drive select A | I/O |
| 18 | DIR | Step direction | I/O |
| 20 | STEP | Step pulse | I/O |
| 22 | WRITE DATA | Write data | I/O |
| 30 | READ DATA | Read data | I/O |
| 34 | DISK CHANGE | Disk change | I/O |