Main technical difficulties and solutions based on large-scale LED display systems

1. Main technical difficulties

① There are tens of thousands of pixels on a large LED display. As the display area increases, the circuit structure becomes more complex.

② In order to ensure a certain display quality, the frame rate should be above 30 frames per second. For example, for a 512×252 pixel monochrome LED display), the data transmission volume per second is at least 480 KB. For color screens and occasions with high display quality requirements, the data transmission volume will increase by integer multiples.

③ When the LED screen is located outdoors, the communication between the upper and lower computers may be hundreds of meters or even thousands of meters, requiring fast and reliable communication.

2. Solution

In view of the first two technical difficulties mentioned above, some coping strategies should be adopted to use a single CPU system instead of a multi-machine system to control a large LED display system.

①Large-scale LED display screens are composed of universal display modules, which have good versatility and embeddability.

② Using 16-bit parallel bus data transmission method, to display the display module at the corresponding position, the column latch unit on the module can be accurately selected, so that the horizontally cascaded LED display modules can be regarded as a continuous storage unit.

③ Using the DMA controller inside the S3C44BOX to transmit and control data can save the CPU time of reading instructions and decoding when using instructions to transmit data, as well as the software overhead of counting, comparing, jumping, etc. when using instructions to transmit data. This allows data transmission to be completed in continuous read and write operations, improving the speed and efficiency of data transmission.