| Signal | Source | Receive | Transmit |
|---|---|---|---|
| Data terminal ready | From VT102 | On | On |
| Data set ready | To VT102 | On | On |
| Request to send | From VT102 | Off | On |
| Clear to send | To VT102 | Off | On |
| Receive line signal detector | To VT102 | On | Off |
| Secondary request to send | From VT102 | On | Off |
| Secondary receive line signal detector | To VT102 | Off | On |