STM32_DAC 实验（正弦波_方波_锯齿波_发生器），使用的stm32f103vet6芯片， 使用KEIL版本3.7编译-STM32_DAC experiments (sawtooth sine _ _ _ square-wave generator), the use of stm32f103vet6 chip, using KEIL compiler version 3.7

基于STM32开发板的串口实验，让大家熟悉串口相关配置的程序设计。-Based on the STM32 development board serial experiments, so that we are familiar with the programming serial port related configuration.