| Number | Name | Description |
| 69 | SRDY | Serialdata input readyinput |
| 70 | so | B-bit serialdata output |
| 71 | SOCK | SO clock input |
| 72 | SORQ | Serialdata outputrequestinput |
| 73 | SOAK | Serial data output acknowledge output |
| 75 | RES | Reset input. Internal pull-up resistor |
| 76 | INT | Intarrupt request input. Internal pull-up resistor |
| 78 | SELC | 1nstruction clock source selection input. Internal pull-down rasistor |
| 79 | SACK1 | FS3 840 selection terminal. Internal pull-down resistor |
| 80 | SACK2 | Fs output clock sou rce selection input. Internal pull-down resistor |
| | |