SPI_2543_uart

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)

无线模块SIM300硬件设计最新资料V4.02。可供从事学习、开发无线通信有关人员参考。(SIM300_HD_V4.02.rar)

51单片机连接射频芯片rc522的单片机程序(51 single connection RF chip microcontroller program rc522)

NXP LPC11u24 cortex-M0 PWM 示例程序(NXP LPC11u24 cortex-M0 PWM sample programs)

JSON脚本C语言使用的案例，包括C语言对JSON脚本的输入和输出。(JSON scripting language used C cases, including the C language for JSON script input and output.)

汽车横、轨道衡,电子汽车衡技术协议说明文档资料(Automotive Wang, railroad track scale, electronic truck scale information technology agreement documentation)

说明：  本课题对基于单片机的交通灯控制系统进行设计。以MCS-51系列单片机为控制核心，设计并制作交通灯控制系统，用于十字路口的车辆及行人的交通管理。东西南北四个路口具有左拐、右拐、直行及行人4种通行指示灯，并分别用计时器显示路口通行转换剩余时间，在特种车辆如119、120通过路口时，系统可自动转为特种车辆放行，其他车辆禁止通行状态。(Traffic light control system based on SCM (Single Chip Microcomputer) is designed in this paper. System requires that MCS-51 series SCM is used as CPU. Traffic light control system should be designed and made .There are four groups light which indicate to turn left, turn right, and go straight ahead and pedestrian access in east, west, north and south four directions. Timer shows traffic conversion remainder time. When special vehicles, such as 119,120 go through, the system can automatically allow special vehicles running and other vehicles is prohibited.)

基于stm32的bldc驱动，有hall位置传感器，电流传感器采样，方波驱动。(Based on stm32 BLDC drive motors, hall position sensor, current sensor sampling, square wave drive.)

ftdi公司的USB设备通信上位机编程。(The PC programing for FTDI S USB device)

本人自己编写的电子贺卡程序，带有音乐播放，和12864的图像显示(I have written an e-card program with music playback, and image display 12864)