Pin assignments of Serial connecter
| Pin number | Signal name | Signal description |
|---|---|---|
| 1 | HSKo | Handshake output. Vh=3.6V; Vl=-3.6V; Rl=450Ω |
| 2 | HSKi | Handshake input. Vh=0.2V; Vl=-0.2V; Rl=12KΩ |
| 3 | TxD- | Transit data (inverted), Vh=0.2V; Vl=-0.2V; Rl=12KΩ |
| 4 | GND | Signal ground |
| 5 | RxD- | Receive data (inverted), Vh=3.6V; Vl=-3.6V; Rl=450Ω |
| 6 | TxD+ | Transit data, Vh=3.6V; Vl=-3.6V; Rl=450Ω |
| 7 | GPi | General-purpose input, Vh=0.2V; Vl=-0.2V; Rl=12KΩ |
| 8 | RxD+ | Receive data, Vh=0.2V; Vl=-0.2V; Rl=12KΩ |
| 9 | PWR | +5V (modem port only) |