To begin with a system that includes multiple levels. Like any monitoring or control system LED screen it has a monitoring system in a server level. Obviously, the field devices in the LED-board are LEDs. A top level or the governing body is the source of the video. At the entrance to the lower level controller is a control screen. It may be, and other video sources to the control screen, the controller transmits to the controllers of individual blocks. Video content can be fed to the screen with the usual office computer; a special server (especially if it is a network of screens); from a computer network, wired or wireless; in a broader sense of the Internet, including from the «cloud»; with video conferencing systems; from a CD or a DVD-player; VCR (uh, remember, had such devices?); camcorder; receiver with satellite and cable television. In some cases, to convert the signal may need to use additional converters or video capture cards.
Fed through a standard video interfaces (modern LED-screens is HDMI, DVI, DisplayPort) video information comes to managing a computer screen, on which the specialized software. Software is also part of the management system. Typically, software for controlling LED screens supplied with the screen. But on the web, you can find plenty of free versions of varying degrees of flexibility. With control of the screen the controller signal is converted to an even lower level — to the controllers of individual cabinets and modules. Since these signals are fed to the LED-driver, converts the control digital signal to analog. Simply put, the current feeding of a force on the individual LEDs. The light sensors may be embedded system adjusts the screen brightness depending on the ambient conditions. Also, the control system may include temperature sensors that automate the on / off heat removal systems and (more rarely) heating to maintain the temperature operating range of LEDs and other equipment LED display. Also, the system can be integrated into devices such as motion sensors or door opening, signaling the attempt to access the internals of the screen for the purpose of vandalism or unauthorized changes video output.
The system may have a different degree of nesting, for example, for one screen, and for the network of screens, for the physical connection «computer screen» and for virtual connection through a wireless network. Everything else in connection with the growth of computer literacy of the population, clearly outpacing the growth of self-consciousness, the control system must include gateways that would protect the control system from unauthorized interference in the work from the outside of the screen. Jokes — jokes, and such cases — are not uncommon.