二阶非线性随机共振

这是stm32f151停止模式的低功耗例程，唤醒方式为RTC定时唤醒。(stm32f151 stop mode example!)

说明：  超声波测距并且oled显示，误差小，精度高，基于51单片机(Ultrasonic ranging and OLED display, small error, high precision, based on 51 single chip microcomputer)

C#串口收发界面,可以在此基础上自由改动(C# Serial Port TX and RX)

用stm32f103对ds1302时钟芯片进行读写，从而获得起内部的时钟数据(Read and write the DS1302 clock chip with STM32F103 to get the internal clock data)

By Brian W. Kernighan and Dennis M. Ritchieyһ

说明：  主要实现了STM32F10X的串口dma，实现了flash操作；并且 直接可以编译运行;(It mainly implements the serial port DMA of STM32F10X, realizes flash operation, and compiles and runs directly.)

【实例简介】懂得都懂，几乎实现工业上所有需求，实现打印图片、各种码、文字等等

对usb 的工作原理进行了细致的分析,还分析了usb整个信息的交流过程.(Technological report of USB project. It analysised the operation principle of usb, and analysised the course of data transfer.)

conversor digitalpara relojes de presision

这是一个进程调度问题~~~~还是有很多的问题哦(This is a process of scheduling problem ~ ~ ~ ~ still has many problems Oh)