| db | Index Level | dcd-off |
| Syntax | dcd {(options} |
| Category | TCL |
| Type | Verb |
| Description |
toggles or displays the status of data carrier detect on the specified port.
If the port number is not specified (as an option), dcd is toggled on the current port. When activated, this protocol allows the system to sense changes in the dcd signal. When the system senses a loss of the dcd signal on a port, it logs the port off. Without any option, the status of the specified port is displayed. On D3/Unix implementations, options and parameters are interchangeable. This command affects the argument "clocal" of the terminal driver, when the "f" option is used. When the dcd is lost, the process is interrupted by a Unix HANGUP signal which forces it to execute the TCL command specified by the "trap" command. (see "trap, TCL, Verb"). An appropriate cable must be used to connect the system to the modem for the dcd signal to be detected. When the "n" option is used, the terminal driver is changed to "-clocal". |
| Options |
n (integer number) Displays or changes settings for port n.
f Toggles dcd off. Data carrier detect is inactive. n Toggles dcd on. Data carrier detect is active. s Suppresses output of status message. x Displays the current carrier detect status (x is any character other than "f", "n", or "s") |
| See Also | trap dcd-off dcd (R83) fc (R83) fc-off (R83) fc-on (R83) modem-off modem-off (R83) port.number dcd-on list-jobs hangup |
| Example |
dcd
[1311] Data carrier detect is off. Tests the current state of dcd. dcd ? [1311] Data carrier detect is off. dcd n [1310] Data carrier detect is on. dcd 16 fs (No output appears. This turns off dcd on port 16 and suppresses the output). |
| Warnings |
The serial cabling must carry the dcd signal for this command to operate properly.
On D3/UNIX implementations, when changing the DCD status of another process, a Unix process must be connected to the Pick virtual machine on the specified PIB, else, and error message is displayed: dcd 22 dcd: Process is not connected. Cannot change setting. [1311] Data carrier detect is off. |
| Compatibility | D3 7.0 AP R83 |
| db | Index Level | dcd-off |