This connector is present on the Macintosh 128K, 512K, 512K enhanced, and Macintosh Plus.
| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | CGND | Chassis ground | |
| 2 | KBD1 | ? | Keyboard clock (input to VIA) |
| 3 | KBD2 | ? | Serial data line |
| 4 | +5V | +5 VDC |
| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | CGND | Chassis ground | |
| 2 | KBD1 | ? | Keyboard clock (input to VIA) |
| 3 | KBD2 | ? | Serial data line |
| 4 | +5V | +5 VDC |