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.
Two ways to fulfill this requirement are through cabling or ditty.
One way to fulfill the DCD requirement is to create a cable and have your device force the signal high. See the Cable Guide for your product.
Note: Cabling and DCD are not an issue for the AccelePort RAS products.
Another way to fulfill the DCD requirement is to enable the forcedcd ditty option. See Setting TTY Options.