(At the DTE)
(At the DCE)
25 PIN D-SUB MALE at the DTE (Computer).
25 PIN D-SUB FEMALE at the DCE (Modem).
Pin | Name | ITU-T | Dir | Description |
---|---|---|---|---|
1 | GND | 101 | - | Shield Ground |
2 | TXD | 103 | Transmit Data | |
3 | RXD | 104 | Receive Data | |
4 | RTS | 105 | Request to Send | |
5 | CTS | 106 | Clear to Send | |
6 | DSR | 107 | Data Set Ready | |
7 | GND | 102 | - | System Ground |
8 | CD | 109 | Carrier Detect | |
9 | - | - | RESERVED | |
10 | - | - | RESERVED | |
11 | STF | 126 | Select Transmit Channel | |
12 | S.CD | ? | Secondary Carrier Detect | |
13 | S.CTS | ? | Secondary Clear to Send | |
14 | S.TXD | ? | Secondary Transmit Data | |
15 | TCK | 114 | Transmission Signal Element Timing | |
16 | S.RXD | ? | Secondary Receive Data | |
17 | RCK | 115 | Reciever Signal Element Timing | |
18 | LL | 141 | Local Loop Control | |
19 | S.RTS | ? | Secondary Request to Send | |
20 | DTR | 108 | Data Terminal Ready | |
21 | RL | 140 | Remote Loop Control | |
22 | RI | 125 | Ring Indicator | |
23 | DSR | 111 | Data Signal Rate Selector | |
24 | XCK | 113 | Transmit Signal Element Timing | |
25 | TI | 142 | Test Indicator |