CANopen主节点除具备CANopen设备的基本条件外,还需具备NMTMaster的功能,即对CANopen网络进行管理。对CANopen主节点的实现提出三种方案:方案1:在CANopen-Chip基础上开发CANopen主站。方案2:通过对CANopen协议栈源代码的二次开发在单片机上实现嵌入式CANopen主站。方案3:利用CANopenMasterAPI在PC机上实现CANopen主节点。
上传时间: 2013-11-02
上传用户:luke5347
介绍一种采用单片机技术和基站器件EM4095的手持式低频RFID读卡器方案。首先对整个系统框架进行说明,然后介绍主要功能模块的设计,给出了各模块的原理图。重点描述了基站器件EM4095的性能参数和功能原理,最后描述了该系统的主程序流程图。 Abstract: In this paper,a handheld RFID reader based on MCU and EM4095 is introduced.At first,the configuration of this system is explained.Then the design of main modules and schematic documents are particularly presented.The parameters and principle of the chip EM4095 are introduced in detail. At last,the main software flow is given
上传时间: 2013-10-18
上传用户:windypsm
气压是气象监测中的一个重要参数,提出了一种气压数据采集模块设计方案,该模块采用数字气压传感器MS5534B、MSP430单片机MSP430F2272和带实时时钟(RTC)64 KB铁电存储器。通过低功耗软件设计方法以微安级整体平均功耗实现了气压数据的采集和存储,适合电池供电的连续高精度气压采集应用。给出了模块的软硬件设计以及MS5534B的性能指标和使用经验。 Abstract: Air pressure is an important parameter in weather monitor.This paper futs forward a new design scheme of low power-air pressure data acquisition module.The module uses a digital output barometer sensor MS5534B,MSP430 microcontroller MSP430F2272 and integrated RTC 64KB FRAM,precision air pressure measurement and storage chip.Another point of this module is low power consumption, so it is well suited for battery powered air pressure data acquisition applications. At the same time,the software and hardware deign of module is presented,And the speciaties and use notices of MS5534B are given.
上传时间: 2014-12-27
上传用户:drink!
针对众多低成本数据采集需求,采用带有片上USB控制器和D/A转换器的混合信号微处理器C8051F340,设计了一款可通过USB接口和LabVIEW图形用户界面实现与PC机联机的数据采集器,同时借助系统的SD卡存储独立实现现场长时间采集数据。该数据采集器成本低,结构简单,体积小,已成功用于工业现场。 Abstract: Aiming at the need of low cost data acquisition, a data acquisition device is designed based on C8051F340 which is a mixed-signal microcontroller and integrates USB controller and A/D controller on a chip.The data acquisition device which can combine with PC by USB interface and LabVIEW graphical user interface,can realize data acquisition. At the same time,it can be solely run a long time in virtue of SD card in field.The date aequisition device features low cost,simple structure and little sharp, and it has been used in industry field.
上传时间: 2014-05-31
上传用户:1109003457
为了解决磁放大器性能测试过程中,需要对其供给不同数值恒定电流的问题,设计了一种基于DAC7512和单片机的数控恒流源系统。该系统采用AT89C51作为主控器件,将计算机发送的电流控制字命令转换为D/A转换器控制字,通过模拟SPI通信接口,写D/A控制字到DAC7512,从而控制其输出相应数字电压值,经差动缩放电路、电压/电路变换电路和功率驱动电路,最后输出恒定电流。实验结果表明,恒流源输出电流调节范围为-45~+45 mA、精度为±0.1 mA,分辨率达0.024 4 mA,具有应用灵活,外围电路简单,可靠性高的特点。该数控直流恒流源也可为相关产品的测试系统研发提供参考。 Abstract: In order to solve the need to supply different values constant current for the magnetic amplifier in testing process, numerical control constant current source system was designed based on DAC7512 chip and microcontroller technology. The system used the AT89C51 as the main chip, which can convert the current control word from computer into to D/A control words. And the system wrote D/A control word into the DAC7512 chip to control the output voltage value by the SPI communication interface, which can output corresponding constant current figures by scaling circuit, the V/I converter and power drive circuit. Experimental results show that the current source output current adjustment range is -45~+45mA, accuracy is ± 0.1mA, and resolution ratio is 0.024 4mA
上传时间: 2014-12-27
上传用户:invtnewer
以AVR单片机ATmega8和USB接口器件PDIUSBD12为核心,基于标准的USB1.1协议,设计一种通用USB接口模块,以满足嵌入式系统中对USB接口的需求。对模块的硬件电路或单片机固件程序的硬件接口层稍加修改即可用于其他各种微处理器。该模块可为各种嵌入式系统增加USB接口,实现与USB主机系统通信。 Abstract: Based on AVR microcontroller ATmega8 and USB interface chip PDIUSBD12, a general USB interface module is designed according to USB1.1 protocol for various requirements of embedded systems. Only with few modifications in circuit or hardware abstract layer of firmware, the module can be used on many types of microprocessors. All kinds of embedded systems can realize high speed and stable communication with USB host systems, owing to the facility of this module.
上传时间: 2014-01-08
上传用户:赵云兴
介绍一种基于单片机的多路温度采集及监控系统,能够测量6路温度信号,具有计算机联网功能,各测量点可以单独监控和设置,可根据用户的需求自动控制。测量温度范围为-10 ℃~200 ℃,控制方式采用模拟量调压模式。该系统具有控制精度高、冲击小等特点。 Abstract: A temperature collecting and surveillance-controlling system based on sing-chip microcomputer is introduced. It can measure 6 channel signal of the temperature,and it has a function of network connection.The temperature measure points can be monitored and located, it can be controlled automatic according to user’s demand.The temperature range is -10℃ to 200℃.The model of control is adjustable voltage with simulation. It features high precision and little impact.
上传时间: 2013-10-23
上传用户:bjgaofei
The PCF8578 is a low power CMOS1 LCD row and column driver, designed to drive dotmatrix graphic displays at multiplex rates of 1:8, 1:16, 1:24 or 1:32. The device has40 outputs, of which 24 are programmable and configurable for the following ratios ofrows/columns: 32¤8, 24¤16, 16¤24 or 8¤32. The PCF8578 can function as a stand-alone LCDcontroller and driver for use in small systems. For larger systems it can be used inconjunction with up to 32 PCF8579s for which it has been optimized. Together these twodevices form a general purpose LCD dot matrix driver chip set, capable of driving displaysof up to 40960 dots. The PCF8578 is compatible with most microcontrollers andcommunicates via a two-line bidirectional bus (I2C-bus). Communication overhead isminimized by a display RAM with auto-incremented addressing and display bankswitching.
上传时间: 2013-10-23
上传用户:顶得柱
为解决传统可视倒车雷达视频字符叠加器结构复杂,可靠性差,成本高昂等问题,在可视倒车雷达设计中采用视频字符发生器芯片MAX7456。该芯片集成了所有用于产生用户定义OSD,并将其插入视频信号中所需的全部功能,仅需少量的外围阻容元件即可正常工作。给出了以MAX7456为核心的可视倒车雷达的软、硬件实现方案及设计实例。该方案具有电路结构简单、价格低廉、符合人体视觉习惯的特点。经实际装车测试,按该方案设计的可视倒车雷达视场清晰、提示字符醒目、工作可靠,可有效降低驾驶员倒车时的工作强度、减少倒车事故的发生。 Abstract: A new video and text generation chip,MAX7456,was used in the design of video parking sensor in order to simplify system structure,improve reliability and reduce cost. This chip included all the necessary functions to generate user-defined OSDs and to add them into the video signals. It could be put into work with addition of just a small number of resistances and capacitors. This paper provided software and hardware implementation solutions and design example based on the chip. The system had the characteristics of simplicity in circuit structure,lower cost,and comfort for the nature of human vision. Loading road test demonstrates high video and text display quality and reliable performance,which makes the driver easy to see backward and reduces chance of accidents.
上传时间: 2013-12-10
上传用户:qiaoyue
提出一种基于单片机AT89C51SND1C的MP3播放系统的设计方案。单片机集成了专用的解码器,使用K9F1208闪存作为外存储器,放音电路采用CS4330,存储文件通过播放器上的USB接口设备从PC机上直接下载,液晶显示采用LCD1602。方案设计简单,性价比高,低功耗,易扩展。由于采用的是通用单片机实现的,可以很容易地移植到其他微控制器系统中,有很强的市场竞争能力和实用价值。 Abstract: A MP3 player design based on microchip AT89C51SND1C was presented, which used K9F1208 Flash chip as the memory circuit and used CS4330 as play chip. Storage files were download from PC through USB interfaces player on the device,and the LCD/602 was used as display screen. This system had characteristics of simple design,low power,easy expand,low cost and high recognition. Using of universual microchip make it easy to transplant to other microcontrol system,and have strong market competitiom and practical value.
上传时间: 2014-12-27
上传用户:佳期如梦