Connector - ITU-TSS X.21Common names: ITU-TSS (CCITT) X.21, ISO 4903CORRECT? 15 PIN D-SUB MALE at the DTE (Computer). 15 PIN D-SUB FEMALE at the DCE (Modem).  | (at the DCE) |  | (at the DTE) |
Pin | Name | Direction | Description |
---|
1 | n/a | --- | Shield (Ground) | 2 | T (A) | Output | Transmit (A) (Data) | 3 | C (A) | Output | Control (A) (Control) | 4 | R (A) | Input | Receive (A) (Data) | 5 | I (A) | Input | Indication (A) (Control) | 6 | S (A) | Input | Signal Timing (A) (Timing) | 7 | B (A) | Input | Byte Timing (A) (Timing) | 8 | G | --- | Ground (Ground) | 9 | T (B) | Output | Transmit (B) (Data) | 10 | C (B) | Output | Control (B) (Control) | 11 | R (B) | Input | Receive (B) (Data) | 12 | I (B) | Input | Indication (B) (Control) | 13 | S (B) | Input | Signal Timing (B) (Timing) | 14 | B (B) | Input | Byte Timing (B) (Timing) | 15 | | --- | unused |
Note: Direction is DTE (Computer) relative DCE (Modem).
|