U disk and Mp3 Driver Program

这是一个实现PC上位机控制下位机（单片机）通过GSm模块发送短信的源代码。-This is a PC-host computer under the control of bit machine (SCM) to send text messages via GSm module source code.

直接数字频率合成（DDS）程序,使用adc9851芯片-Direct Digital Synthesis (DDS), the use of chip adc9851

基于51单片机系统，利用AD转换芯片ADS7841，数码管驱动芯片CH452，以及CD74HC4051、CD74HC259、CD74HC154、74HC244等接口芯片实现二十路以上的电压监测、显示与通断控制。编程环境：keil-Based on 51 single-chip microcomputer system, using AD conversion chip ADS7841, digital tube driver chip CH452, and CD74HC4051, CD74HC259, CD74HC154, 74HC244 interface chip such as the way to achieve more than twenty-voltage monitoring, display and on-off control. Programming environment: keil

写单片机的可以看看17种使用的小软件这是1-RUANJIAN

CPU卡读写，符合7816标准。经测试完全可以使用。-CPU card reader, in line with the 7816 standards. Been tested and can be used.

单片机模拟spi通讯，可用于对spi接口的存储器的读写访问-Single-chip simulation spi communication, can be used to spi interface to read and write memory access

单片机下CRC7校验码生成程序，主要用于生成MMC卡命令的CRC7校验码。-Microcontroller CRC7 correcting code generation process, mainly used to produce MMC card orders CRC7 correcting code.

c8051f020的pca频率输出，针对c8051f020的实验系统-err

本系统主要用于旅游景点记录游客人数，并限制旅客的流量。采用红外传感器通过检测人体红外并对通过人数进行计数，通过红外对管将检测到的数据发送至单片机，单片机处理后送至数码管显示，数码管显示的数据即为通过的人数，并通过设定值限制旅客数量。当游客超量是系统将给出相应的提示，禁止游客再进入。以更好的保护旅游景点的生态环境。-This system is mainly used for tourist attractions recording the number of visitors and limit the flow of tourists. Use of infrared sensors by detecting the human body by infrared and number of people count on the tube will be detected by infrared the data sent to the MCU, MCU after treatment sent to the digital LED display, digital LED display of the data shall be the number of through and through setting limits the number of passengers. When the visitors over-the system will give the appropriate prompts to prohibit visitors from re-entering. To better protect the tourist attractions of the ecological environment.

绝对正确的SAA7121寄存器初始化值，包括PAL、NTSC,不能用你找我-SAA7121 absolutely correct register initialization value, including PAL, NTSC, you should not use me