There are two types of LED digital tube display mode, static display and dynamic display. Among them, the static display means that the display driver circuit has a lock function, andafter transmitting the data to be displayed, the microcontroller does not control the LED and retransmits the new display data to the next display. .. The statically displayed data is stable and requires less CPU time. For static displays, each displayshould use a separate latch with the I / O interface energy function of this interface for the bar segment font code.