脉冲拨号芯片实现单片机应用系统键盘的设计

The Design of Keyboard in Application System of Single Chip Computer by Pulse Dial Chip

提出一种应用电话脉冲拨号芯片作为单片机应用系统键盘电路的实现方案 ,给出具体的接口电路以及相应的软件设计方法 ,达到了用最少的I/O资源 。

In this article, a design proposal of keyboard circuit in application system of single chip computer by using telephone pulse dial chip is put forward. The concrete I/O circuit and the corresponding software designing method are also presented here. By which, the fewest I/O resourses can be used to carry out the realization of recognizing more keys.