### Data Carrier Detect

In some cases, depending on your operating system requirements and/or your device requirements, it may be necessary for the Data Carrier Detect (DCD) signal to be active on a port before it will function.

There are two ways to fulfill this requirement.

#### Cabling

One way to fulfill the DCD requirement is to create a cable and have your device force the signal high. See the Digi One RealPort and PortServer Cable Guide.

#### ditty-rp

Another way to fulfill the DCD requirement is to enable the forcedcd ditty-rp option. See Setting TTY Options.