lights Industry Jun 1,2022 00:00 247 0
Original author: Stage LightingFrom: Stage Lighting
The DMX512 protocol is a data dimming protocol proposed by the United States Stage Lighting Association (USITT). It provides a protocol standard for communication between lighting controllers and lighting equipment. Because it was proposed in 1990, the full name of the protocol is It is USITTDMX512 (1990). The proposed protocol provides a good standard for controlling lighting equipment using digital signals. DMX512 is a digital dimming protocol, which can be used to digitally control dimmers and other control equipment in stages, theaters, studios and other places. It is suitable for a point-to-multipoint master-slave control system. The multi-point bus structure is adopted, there is no information path blocking problem, the connection is simple, and the reliability is high. Although the lighting control system has developed into a networked control system, the DMX512 signal system is still the most widely used system at present. Even if it is a large-scale networked lighting control system, the control end still uses a large number of DMX512 signal control methods. The DMX512 protocol is suitable for a point-to-multipoint master-slave control network system. According to the requirements of DMX512 data transmission rate and the characteristics of distributed control network, the design of its physical layer adopts RS-485 bus transceiver, and the bus uses a pair of twisted pairs to realize the connection between the dimmer and the dimmer. The RS-485 bus adopts balanced transmission and differential reception, with high receiving sensitivity and strong anti-interference ability, and the signal transmission distance can reach 1000m. If the dimmer is too far from the dimmer, an amplifier or splitter can be used to boost the signal. The DMX512 protocol adopts a bus-type structure, but the data is unidirectionally transmitted from the dimmer to the dimmer, so there is no phenomenon of information blockage due to competition between the various dimmers for the right to use the bus. |