The asynchronous control method of LED electronic screen means that the LED electronic screen has the ability of storage and automatic playback. The modified text and non gray images on the PC are transmitted to the LED electronic screen through the serial port or other network interface, and then the LED electronic screen automatically plays offline. Generally, there is no multi gray display ability. It is mainly used to display text and simple graphic information, and can be connected to multiple screens.
The master PC transmits the information to be displayed and all kinds of control instructions to the LED electronic screen control card through serial communication. The LED electronic screen control card contains MCU and memory. The on-screen control card stores the information and displays it on the LED electronic screen according to the instructions.
The asynchronous graphic LED electronic screen mainly includes:
① The host computer of the adapter adopts the RS232 protocol of serial port, and goes online through RS232-RS485 adapter.
② The control card receives the information to be displayed and various control instructions transmitted by PC through serial communication. The control card contains MCU and memory. The on-screen control card stores the information and displays it on the LED electronic screen according to the instructions. The features are as follows:
a. When the number of vertical points is less than 128, the number of horizontal points can be as long as 2000. If it is 16 points in the longitudinal direction, it can reach 4000 points in the transverse direction.
b. It can be controlled by computer and displayed offline.
c. The large capacity memory supports Chinese characters and many proprietary characters in the first and second level font library, with a storage capacity of 16 screens.
d. With calendar real-time clock function.
e. The information can be saved for one year after power failure.
③ The special communication led electronic screen LED program editing and broadcasting software of upper computer conforms to the control protocol of LED graphic display screen. It is satisfied with the modification and broadcasting of text and image programs of multiple monochrome or dual color LED electronic screens with different lengths and widths. A maximum of 16 shows can be sent at a time.
④ Single network cable (four core) adopts four wire system: one pair of DTP is accepted and the other pair is sent. The communication distance is 1200 meters. The bus type networking structure is selected, and the maximum load is 32 lower computers.
⑤ LED graphic display screen control protocol
a. This agreement supports dot matrix monochrome and dual primary color LED electronic screen.
LED electronic screen control system technology
