dac

滤波器广泛应用于数字信号处理、通信、自动控制领域,但设计可变宽频带有源滤波器则比较困难。利用单片机控制参数可编程的双二阶通用开关电容有源滤波器,精确设置有源滤波器的中心频率f，品质因数Q及有源滤波器的工作方式。本系统主要分为两个部分:即程控滤波器和程控放大器。程控放大器电压增益为40dB，通过单片机控制DA进行分压，可精确实现要求的10dB步进，误差小于0.5 ，通带为100Hz-500KHz，输入电压峰－峰值范围为10mV，在输入范围内无明显失真。由MAX264为核心的滤波器，可设置为高通、低通滤波器。通过单片机直接给出控制频率，使-3dB截止频率在1KHz-20KHz内可调，步进1KHz，误差小于1 。整个系统以52单片机为控制核心，电路简单，性能稳定，且具有较高精度，滤波参数调节通过单片机控制，较为方便。(Filters are widely used in digital signal processing, communications, automatic control area, but the design variable wideband active filter is more difficult. Control parameters using single-chip programmable universal switched-capacitor biquad active filter, active filter accurately set the center frequency f, quality factor Q and the active filter works. The system is mainly divided into two parts: the program-controlled filters and programmable amplifiers. Programmable amplifier voltage gain of 40dB, the DA through the partial pressure of single-chip control, can accurately achieve the required 10dB step, the error is less than 0.5 , passband to 100Hz-500KHz, input voltage peak- the range of 10mV, the input range no significant distortion. By the MAX264 as the core of filter can be set to high pass, low pass filter. Given directly by the microcontroller controls the frequency, the-3dB cutoff frequency at 1KHz-20KHz adjustable, step 1KHz, error is less than 1 . The entire system for)

用电脑串口控制单片机流水灯状态,用电脑串口控制单片机流水灯状态(Serial control with a computer chip light water status)

好的声文同步程序，值得学习，适合于初学者，给大家共同分享(Good sound text synchronization process, it is worth learning, suitable for beginners, for everyone to share)

实现对气体流量表的基于音速喷嘴的自动检定(testing for the gas flow meters based on stangdard acoustic nozzles)

SSD6实验，该实验练习指导如何分析测量程序的性能。这个实验完成后，你应该能够  理解如何测量程序的运行时间、  调整你的计划，以更快的知道的重要性(This laboratory exercises guide you how to measure the program’s performance using profiling. On completion of this laboratory, you should be able to  Understand how to measure the program’s running time  Be aware the importance of tuning your program to be faster)

基于单片机STC89C51和74LS164的多功能数字万用表(Based on microcontroller STC89C51 and 74 ls164 multi-function digital multimeter)

根据设计任务书的要求，本次设计为110kV 变电站电气一次部分初步设计，并绘 制电气主接线图及其他图纸。该变电站设有两台主变压器，站内主接线分为110kV、 35kV 和10kV 三个电压等级。各个电压等级分别采用单母线分段接线、单母线分段带 旁母接线和单母线分段接线(From the guide of engineering design assignment, we have to design primary power-system of 110kV substation and draw main electrical one-line diagram and others. There are two main transformer in the substation in which main electrical connection can be divided into three voltage grades: 110kV, 35kV with 10kV.It deposits sectionalized single bus bar scheme, sectionalized single and transfer bus bar and sectionalized single bus bar scheme per grade.)

测试电脑鼠各个红外探测器的算法，可自行调试(Test each computer mouse infrared detector algorithm, self-debugging)

基于51单片机的 红外+LCD+继电器C程序显示 实现的功能较多，比较适合初学的人。(Based on 51 single-chip infrared+LCD+ relay C program display of more functions, more suitable for beginners person.)

利用stm32控制OV2640软件二值化采集数据，进行图像识别，可以操作机械臂打节奏大师(Use stm32 control OV2640 software binary data acquisition, image recognition, playing rhythm master manipulator can be operated)