DMX512 System Introduction
The DMX512-A protocol was first developed by the American Theater Association in 1985. The current DMX512-A protocol is a modified version released in 1998. Currently, the cultural industry standard of the People's Republic of China (WH/T 32-2008) is adopted in China, which has strict regulations on the data format and physical layer of the control information of the host computer, providing a unified standard interface.
The DMX512 protocol is suitable for point-to-point master-slave control network systems. Based on the requirements of DMX512 data transmission rate and the dispersed characteristics of the control network, an RS-485 transceiver is designed. The bus can be connected between the master controller and the sub controller, as well as between the sub controller and the fountain, using a pair of twisted pair cables. The RS-485 features balanced transmission and differential reception, with high receiving sensitivity and strong anti-interference ability. The signal transmission distance can reach up to 100 meters. If the main controller is too far away from the sub controller, a relay amplifier or signal isolation amplifier can also be used to enhance the signal.
The DMX512-A protocol stipulates that the interconnection between the main controller and the sub controller, as well as between the sub controller and the device, adopts a bus type network structure. Due to the one-way transmission of data from the main controller to the sub controller and from the sub controller to the fountain, there is no phenomenon of information blockage caused by the competition for bus usage rights between sub controllers and devices. The cultural industry in our country has proposed the DMX512-A control protocol (WH/T 32-2008) and established industry unified standards. Fountain control should also be referred to and implemented
