51单片机的一些小程序，都是自己平时练习所写的，包括点亮led灯，键盘扫描等等。很适合初学者-51 microcontroller some small programs, are their usual practice written, including light led lights, keyboard scan. It is suitable for beginners

简易计算器，利用4乘4矩阵键盘，51单片机在LED显示屏上实现简易计算器功能(Based on the 4 x 4 matrix keyboard, 51 microcontroller simple calculator functions on the LED display)