STM32F103 4*4矩阵键盘,有需要的朋友看一下(STM32F103 4*4 matrix keyboard, have a need of friends to look at it)

从零开始学STM32，运用独立按键控制蜂鸣器发出声音，适用于有51单片机基础的新手。(Learn STM32 from scratch, use independent buttons to control the buzzer to make sounds. It is suitable for beginners who have a basis of 51 SCM.)

stm32入门范例程序，配套开发板CT117E,内含：LED,Systick,串口，LCD,键盘，中断，是学习stm32的基础与实用程序，keil编译