1，消除按键的抖动问题 因为按键在闭合或断开过程中出现一段抖动期，主要由于按键的不稳定性引起的，这时会呈现一串页脉冲，时间的长短和开关的机械特性有关。一般在5ms~10ms之间。为保证CPU对键的一次闭合作一次处理，必须去抖动。在键的稳定闭合或断开时读键的状态。 2，据EICE51原理图编写并调试一个键输入子程序，其功能为判断键盘上有无键输入，若有键入，作去抖动处理后，计算输入键的键号送累加器A。-eliminate jitter button issues as keys or disconnect the closure process for some jitter period, mainly due to the instability of the keys to the cause, then it will result in a bunch of pages pulse, the duration and switches on the mechanical properties. General ~ 10ms between 5ms. To ensure that the CPU in a pair of keys a close cooperation, must go jitter. The key to the stability closed or disconnected when reading the key state. 2, EICE51 schematics prepared and debug a key input subroutine, and its function of determining whether keys on the keyboard input, if typing for to handle jitter, the admission of Bond, Bond sent accumulator A.