KeyScan

代码说明：

  个人在keil下编写的基于89C52的LJD-5100开发板的键盘扫描程序，根据CH451感应外部中断，并根据CH451键盘矩阵代码，计算键值(Individuals in keil prepared 89C52-based LJD-5100 development board of the keyboard scanning process, according to sensitive external interrupt CH451, CH451 keyboard matrix, in accordance with the code to calculate key)