NCD Command Tool for dos 

The NCD.EXE allows you to control NCD products directly from a command line interface in DOS. NCD.EXE does NOT require 3rd party tools or components, as it speaks directly to DOS.
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NCD Device Development Lib 

NCD relay controllers allow computer controlled switching from the RS232 serial port of a microcontroller or computer.NCD video switchers allow computer controlled multiplexing of audio or vide signals from the RS232 serial port of your computer.
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