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
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
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
The CAT93C46 is a 1 kb Serial EEPROM memory device which isconfigured as either 64 registers of 16 bits (ORG pin at VCC) or 128registers of 8 bits (ORG pin at GND). Each register can be written (orread) serially by using the DI (or DO) pin. The CAT93C46 features aself−timed internal write with auto−clear. On−chip Power−On Resetcircuit protects the internal logic against powering up in the wrongstate.
上传时间： 2013-11-20
上传用户：ynzfm
引言 在数字信息传输中，基带数字信号通常要经过调制器调制，将频率搬移到适合信息传输的频段上。2FSK就是用数字信号去调制载波的频率（移频键控），由于它具有方法简单、易于实现、抗噪声和抗衰落性能较强等优点，因此在现代数字通信系统的低、中速数据传输中得到了广泛应用。 直接数字频率合成技术(DDS)将先进的数字处理技术与方法引入信号合成领域。DDS器件采用高速数字电路和高速D/A转换技术，具备频率转换时间短、频率分辨率高、频率稳定度高、输出信号频率和相位可快速程控切换等优点，可以实现对信号的全数字式调制。
上传时间： 2014-12-27
上传用户：1427796291
基于AT89C52单片机的步进电机控制系统设计 摘 要: 提出了一个由AT89C52单片机控制步进电机的实例。可以通过键盘输入相关数据, 并根据需要, 实时对步进电机工作方式进行设置, 具有实时性和交互性的特点。该系统可应用于步进电机控制的大多数场合。实践表明, 系统性能优于传统的步进电机控制器。 关键词: 单片机; 步进电动机; 直流固态继电器; 实时控制 ABSTRACT: A stepp ing motor control system based on AT89C52 chip microcomputer was described.The data can be inputwith keyboard, and stepp ingmotorwas controlled by these data. According to the demand, users can set the workingmodel of stepp ingmotor in real2time. This system can be widely used in stepp ing motor controlling. The p ractice showed that the performance of this system outdid the tradi-tional stepp ing motor controller.
上传时间： 2013-11-22
上传用户：vodssv
The CAT28LV64 is a low voltage, low power, CMOS Parallel EEPROM organized as 8K x 8−bits. It requires a simple interface for in−system programming. On−chip address and data latches, self−timed write cycle with auto−clear and VCC power up/down write protection eliminate additional timing and protection hardware. DATA Polling and Toggle status bit signal the start and end of the self−timed write cycle. Additionally, the CAT28LV64 features hardware and software write protection.
上传时间： 2013-11-16
上传用户：浩子GG
本文介绍了一种基于单片机的健身车转速测量系统。该系统具有电路简单、使用方便等特点。文中详细介绍了该系统的工作原理,并且给出了它的硬件原理图和软件设计程序框图。关键词:转速 单片机 测量ABSTRACT :This paper introduces a measuring system of the rotational velocity of exercise bike based on single - chip microcomputer . It has such advantages : simple circuit ,convenient use and so on. The work principle is presented in detail in this paper and the block diagram of hardware and program flow chart are giv2 en as well .KEYWORDS :Rotational velocity Single - chip microcomputer Measuring
上传时间： 2013-11-02
上传用户：源弋弋
本文依据集成电路设计方法学，探讨了一种基于标准Intel 8086 微处理器的单芯片计算机平台的架构。研究了其与SDRAM，8255 并行接口等外围IP 的集成，并在对AMBA协议和8086 CPU分析的基础上，采用遵从AMBA传输协议的系统总线代替传统的8086 CPU三总线结构，搭建了基于8086 IP 软核的单芯片计算机系统，并实现了FPGA 功能演示。关键词：微处理器； SoC；单芯片计算机；AMBA 协议 Design of 8086 CPU Based Computer-on-a-chip System（School of Electrical Engineering and Automation, Heifei University of Technology, Hefei, 230009,China）Abstract: According to the IC design methodology, this paper discusses the design of one kind of Computer-on-a-chip system architecture, which is based on the standard Intel8086 microprocessor,investigates how to integrate the 8086 CPU and peripheral IP such as, SDRAM controller, 8255 PPI etc. Based on the analysis of the standard Intel8086 microprocessor and AMBA Specification,the Computer-on-a-chip system based on 8086 CPU which uses AMBA bus instead of traditional three-bus structure of 8086 CPU is constructed, and the FPGA hardware emulation is fulfilled.Key words: Microprocessor; SoC; Computer-on-a-chip; AMBA Specification
上传时间： 2013-12-27
上传用户：kernor
