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navigation, search  DMX512-A is a standard for digital
communication networks that are commonly used to control stage
lighting and effects. It was originally intended as a
standardized method for controlling light dimmers which had,
prior to DMX512, employed various incompatible, proprietary
protocols. However, it soon became the primary method for
linking not only controllers and dimmers, but also more advanced
fixtures and special effects devices such as fog machines and
moving lights.  DMX512 employs EIA-485 differential signaling at
its physical layer, in conjunction with a fixed-size, packet
based communication protocol. It is unidirectional and does not
include automatic error checking and correction. Consequently,
it is not used in safety-critical applications such as
controlling pyrotechnics or laser lighting display where
audience or performer safety is at risk. Instead, RDM or MIDI
are sometimes used for this task.  Media in category "DMX512