Floppy Drive and Interface
Each signal is identified by its pin number on the cable used to connect the floppy drive to it's drive adapter. Note that there is a cable for the 3 1/2 drive and a different one for the 5 1/4 drive, yet the pin assignments are the same on both drives and cables.
| Pin No. | Signal Name |
| 1 | Ground |
| 2 | Density 1=Low/0=High |
| 3 | Ground |
| 4 | N/C |
| 5 | Ground |
| 6 | N/C |
| 7 | Ground |
| 8 | 0=Index |
| 9 | Ground |
| 10 | 0=Motor Enable Drive 0 |
| 11 | Ground |
| 12 | 0=Drive Select 1 |
| 13 | Ground |
| 14 | 0=Drive Select 0 |
| 15 | Ground |
| 16 | 0=Motor Enable Drive 1 |
| 17 | Ground |
| 18 | 0=Direction Select |
| 19 | Ground |
| 20 | 0=Head Step |
| 21 | Ground |
| 22 | Write Data |
| 23 | Ground |
| 24 | 0=Write Gate |
| 25 | Ground |
| 26 | 0=Track 00 |
| 27 | Ground |
| 28 | 0=Write Protect |
| 29 | Ground |
| 30 | Read Data |
| 31 | Ground |
| 32 | 0=Head Select |
| 33 | Ground |
| 34 | 1=Disk Change/0=Ready |
