Issue link: https://www.e-digitaleditions.com/i/1255991
July/August/September 2020 I 19 Control hardware and software are the heart of any AV system. Control hardware provides physical links between the human users and the devices that accept, process, and display the multimedia AV content. Control software lives inside the control hardware, providing the smarts to implement the user interface and to translate user requests into machine commands. Together, they shape the user experience not only for meeting-goers looking to harness the power of multimedia to present their ideas, but also for the technicians tasked with configuring and maintain- ing the AV systems. the User Experience People who use an AV system just want it to work. Their perception of the value of an AV system is based solely on the user interface through which they access the sys- tem. Simple operation, functionality, and the aesthetics affect perception. For simple applications, button panels translate the settings of physical switches and volume control knobs into commands that control AV system devices. For more complex applications, there are touch- ELEMENTS OF THE AV CONTROL SYSTEM The User Interface Makes or Breaks FIGURE 2: Controller rear view showing electronics module and wide variety of control signal connections. FIGURE 1: AV system user interfaces (left to right) include wall-mount button panel, table-top touchpanel, and touchpanel GUI remoted to a tablet device. panel graphical user interfaces (GUIs). Touchpanels process taps, finger motions and mouse clicks made by users on virtual buttons, virtual sliders and nested menus into commands for the AV system. These GUIs can be hosted on touchpanels, computers, tablets and smart- phones. For both button panels and touchpanels, the most important attributes are simplicity and intuitive response that are made possible by the right blend of hardware and software (Figure 1). Controllers—The Hardware Controllers are well suited for smaller AV systems, such as those used for classrooms and single-display presenta- tion applications. Typically, they are a button panel and control processor in one. Often, they are packaged as wall plates with several customizable, configurable mechani- cal buttons and perhaps a volume control knob. An inte- gral electronics module houses a microprocessor and memory. The microprocessor runs software or firmware that translates user button-presses or knob-turns into appropriate commands for managing the AV equipment. The electronics module also contains a variety of inter- face circuits—including Ethernet, serial RS-232/RS-422, discrete DC bi-level digital, and infrared—that send com- mands and gather status from the AV equipment being controlled. All this fits into a standard two-gang junction box and is powered by low voltage DC from an external power supply or power over ethernet (PoE) (Figure 2).