根据键盘电路，键盘选择程序扫描方式工作，利用CPU在完成其它工作的空闲

According to the keyboard circuit, the keyboard selects the program scan mode to work, and uses the CPU to call the keyboard scan subroutine during the idle time of completing other tasks to process the key input requirements. When executing the key function processing program, the CPU no longer responds to other key input requests. The keyboard processing program flowchart of this system is shown in Figure 4-4. Use software delay method to eliminate jitter.

According to the keyboard circuit, the keyboard selector scan works, using the CPU in the idle time to complete other work, call the keyboard scanner subroute, to deal with the key input requirements. When performing a key function handler, the CPU no longer responds to other key entry requirements. The keyboard handler flowchart for this system is shown in Figure 4-4. Use software delay to eliminate jitter.

According to the keyboard circuit, the keyboard selects the program scanning mode to work, and uses the CPU to call the keyboard scanning subroutine in the idle time to complete other work to process the key input requirements. When executing the key function processing program, the CPU no longer responds to other key input requirements. The flow chart of keyboard processing program of the system is shown in Figure 4-4. Software delay is used to eliminate jitter.<br>