Generally, senior technicians know that LED advertising screens need to have high display performance and effects. However, in order to facilitate control, the LED advertising screen control system should have sufficient input and output interfaces and remote communication functions. The system structure of our LED advertising screen controller based on HDMI1.3 technology. The system can be divided into: 6 analog inputs, 1 VGA input, 2 DVI inputs, status indication, real-time clock, and optical fiber data transmission models.
At present, LED advertising screens are mainly divided into two types: synchronous display and offline display according to the data transmission method. The LED advertising screen control introduced in this article is a synchronous display system, that is, an embedded system is used to provide a video source for the LED advertising screen, which can reduce costs, and has high feasibility and flexibility, and is easy to construct. . The independent video LED advertising screen system is completely separated from the control of the computer, and can itself realize functions such as communication, video playback, data distribution, and scanning control. Since the controller is to control the large frame data, it is necessary to distribute the data provided by the video source, and correctly send the data of different rows and columns to different controllers.
The data correction sub-module receives the data input from the front end, and stores these data in SDRAM after point-by-point correction. Then divide the field data into 8 groups and send them to the LED advertising screen distributor at the same time.
FPGA reads the input data according to the timing relationship, and performs the next step. Since the parameters of the LED advertising screens cannot be completely consistent during the production process, in order to obtain a good image display effect, the LED tubes must be screened.
When data is distributed and sent, the signals are transmitted in the form of LVDS. Because this system adopts MCU+FPGA architecture, it realizes real remote network operation. It can not only be used as a general LED advertising screen controller, but also can form a large outdoor advertising media network with various display nodes. According to HDMI technology to control the LED advertising screen, the brightness is appropriate, the resolution is fine, the field scanning frequency is high, and the pixels are high. It can be used for outdoor broadcast-level applications. The design adopts a single-point correction, which allows purchasers to relax LED requirements in terms of brightness and color, and related procurement costs are also reduced.
