The HR-16P is a programmable RS-232 serial device designed to control any device with a serial port based on sensing level changes (open-to-close and close-to-open, or digital high to low and vice versa).
The HR-16P has 16 discrete inputs that sense a DC voltage level or contact closure (see figure below for input terminal configuration). It detects both "low-to-high" and "high-to-low" transitions of these discrete inputs and issues corresponding commands out the serial port of the HR-16P to the serial device (typically a video projector but not limited to that).
The commands can be any ASCII (or non-ASCII) data with programmable delays embedded in the string. The commands can also be a complex multi-part string, such as having commands with delays and then more commands.
Hall Research provides a powerful Windows based application that is used to create the data files and for uploading them to the HR-16P, via a supplied serial cable. The latest version of this file is available for free download (see next section below)
The unit is supplied with a 5v DC power adapter and a serial cable (null-modem or crossover cable for programming the unit). The inputs are on screw terminals with headers that can be unplugged for easy assembly.
A typical application would be to send commands to turn a projector on and off or select different inputs.