Saber_ref

用简单的51单片机制作八路温度巡检仪表，绝对好用，AD用的ADC0809,传感器用的PT100(Making eight road temperature inspection instruments with a simple 51 single chip microcomputer)

基于单片机的数控开关电源设计，带仿真和详细程序。(NC-based single-chip switching power supply design, with simulation and detailed procedures.)

nxp 的lpc1788中文手册，很详细的介绍了LCD等模块作用，适合开发gui用(nxp of lpc1788 Chinese manual, very detailed introduction to the role of LCD module, suitable for the development of gui use)

The ebook and solution manual of Eugene Hecht optics book which is very standard in US universities

stm32控制超声波精确快速测距，误差在0.1cm，通过LCD显示测量值(STM32 control ultrasonic quick and accurate location, the error in 0.1cm, as revealed by LCD measurements)

大多数自行车速度表工作通过使用霍尔效应传感器固定在自行车前叉。磁铁是附加到前轮上的辐条之一,它将与霍尔效应开关一次革命的车轮。速度计监测传感器计数轮革命。如果知道车轮的直径,距离可以很容易地计算如果你知道有多少革命的车轮。此外,如果时间完成革命,平均速度也可以计算出来。 对于这个问题,您将编写一个程序来确定总距离(英里)和平均速度(英里每小时)考虑到车轮直径,革命的数量和总时间的旅行。你可以假定前轮从未离开地面,并没有下滑或打滑。(Most bicycle speedometers work by using a Hall Effect sensor fastened to the front fork of the bicycle. A magnet is attached to one of the spokes on the front wheel so that it will line up with the Hall Effect switch once per revolution of the wheel. The speedometer monitors the sensor to count wheel revolutions. If the diameter of the wheel is known, the distance traveled can be easily be calculated if you know how many revolutions the wheel has made. In addition, if the time it takes to complete the revolutions is known, the average speed can also be calculated. For this problem, you will write a program to determine the total distance traveled (in miles) and the average speed (in Miles Per Hour) given the wheel diameter, the number of revolutions and the total time of the trip. You can assume that the front wheel never leaves the ground, and there is no slipping or skidding.)

C51单片机例程，通过红外线用按键使数码管显示键值(C51 microcontroller routines, through infrared button digital tube display key)

Some code examples for NMEA gps and SIM800

基于DHT11的湿度感应加湿器，基于51单片机，采用C语言编程(Based DHT11 humidity sensor humidifiers, based on 51, using C language programming)

说明：  ntp客户端连接， 嵌入式C， 通过ntp服务器同步并更新本地时间，同步，计算，修改 ntp客户端连接， 嵌入式C， 通过ntp服务器同步并更新本地时间，同步，计算，修改(syncronize with time server. syncronize with time server.)