The VISA probes for LabVIEW 7.0 greatly extend the amount of relevant
information displayed when using LabVIEW probes on VISA refnums. They are used
automatically by LabVIEW in place of the generic probe when they are
installed.
Occasionally, we are tasked with designing circuitry for aspecific purpose. The request may have customer originsor it may be an in-house requirement. Alternately, a circuitmay be developed because its possibility is simply tooattractive to ignore1. Over time, these circuits accumulate,encompassing a wide and useful body of proven capabilities.They also represent substantial effort. These considerationsmake publication an almost obligatory propositionand, as such, a group of circuits is presented here. This isnot the first time we have displayed such wares and, giventhe encouraging reader response, it will not be the last2.Eighteen circuits are included in this latest effort, roughlyarranged in the categories given in this publication’s title.They appear at the next paragraph.
為了使音頻信號(hào)分析儀小巧可靠，成本低廉，設(shè)計(jì)了以2片MSP430F1611單片機(jī)為核心的系統(tǒng)。該系統(tǒng)將音頻信號(hào)送入八階巴特沃茲低通濾波器，對(duì)信號(hào)進(jìn)行限幅放大、衰減、電平位移、緩沖，并利用一單片機(jī)負(fù)責(zé)對(duì)前級(jí)處理后的模擬信號(hào)進(jìn)行采樣，將采集得到的音頻信號(hào)進(jìn)行4 096點(diǎn)基2的FFT計(jì)算，并對(duì)信號(hào)加窗函數(shù)提高分辨率，另一單片機(jī)負(fù)責(zé)對(duì)信號(hào)的分析及控制顯示設(shè)備。此設(shè)計(jì)精確的測(cè)量了音頻信號(hào)的功率譜、周期性、失真度指標(biāo)，達(dá)到較高的頻率分辨率，并能將測(cè)量結(jié)果通過(guò)紅外遙控器顯示在液晶屏上。
Abstract:
o make the audio signal analyzer cheaper， smaller and more reliable， this system sends the audio signal to the eight-order butterworth filter， and then amplifies， attenuates， buffers it in a limiting range， transfers the voltage level of the signal before utilizing two MSP430F1611 MCU to realize the audio analysis. One is charged for sampling and dealing with the processed audio signal collected by the 4096 point radix-2 FFT calculation and imposes the window function to improve the frequency resolution. The other one controls the display and realizes the spectrum， periodicity， power distortion analysis in high resolution which is displayed in the LCD screen through the infrared remote control.
該系統(tǒng)由單片機(jī)89S52控制模塊，程控寬帶放大模塊，整形模塊，F(xiàn)PGA內(nèi)頻率、相位差測(cè)量模塊等構(gòu)成，采用等精度測(cè)頻法測(cè)出頻率和周期，可測(cè)量有效值為0.01～5V，頻率范圍1Hz～20MHz信號(hào)的頻率、周期信號(hào)，精度高達(dá)10-6。采用計(jì)數(shù)法測(cè)量相位差，該系統(tǒng)可測(cè)量有效值0.5～5V，頻率10Hz～100kHz信號(hào)的相位差，精度為1°。系統(tǒng)功能由按鍵控制，測(cè)量結(jié)果實(shí)時(shí)顯示，人機(jī)界面友好。
Abstract:
The system consists of the following functional blocks:89S52microcontroller controlling module,programmable amplifier module,comparator module,frequency and phase difference testing module in the FPGA.The system use the equal accuracy frequency-examining technique it measures frequency and circle of signal which its ranges is from1Hz to20MHz and the amplitude of which its range is from0.01Vrms to5Vrms,precision is up to10-6.Using of count method,the system detects the phase difference of signal,the amplitude of whic its range is from0.5Vrms to5Vrms and the frequency of which its ranges is from10Hz to100kHz,precision is up to1°,The system functions is controlled by certain keys,measurement results are displayed in real-time and it is friendly interface.
介紹一種多功能音樂(lè)播放器，它是以AT89S52單片機(jī)為核心，并輔有一些外圍器件，采用匯編語(yǔ)言編寫程序，實(shí)現(xiàn)多功能音樂(lè)播放，歌曲自動(dòng)循環(huán)播放和使用琴鍵自編曲目功能。此外，彩燈顯示歌曲節(jié)奏，按鍵跳轉(zhuǎn)到喜愛(ài)曲目，液晶顯示當(dāng)前播英文曲目。并給出了系統(tǒng)軟硬件設(shè)計(jì)。
Abstract:
It introduces a multifunctional music player,taking AT89S52 single-chip microcomputer as hardware control core and using some peripheral elements.Programmes are compiled in assembly language to act as expected.There are two functional modes in this system.One is to make the music play automatically and consecutively,the other is to compose new songs through keys.In addition,lights show the pace of music and the English names can be displayed in the liquid crystal screen.With perfect combination of hardware and software,the music player can meet many music lovers’needs for multifunctional music player.And the hardware and software of the system are given.
為解決輸油管道溫度壓力參數(shù)實(shí)時(shí)監(jiān)測(cè)的問(wèn)題，設(shè)計(jì)了以C8051F930單片機(jī)作為控制核心的超低功耗輸油管道溫度壓力遠(yuǎn)程監(jiān)測(cè)系統(tǒng)。現(xiàn)場(chǎng)儀表使用高精度電橋采集數(shù)據(jù)，通過(guò)433 MHz短距離無(wú)線通信網(wǎng)絡(luò)與遠(yuǎn)程終端RTU進(jìn)行通信，RTU通過(guò)GPRS網(wǎng)絡(luò)與PC上位機(jī)進(jìn)行遠(yuǎn)程數(shù)據(jù)傳輸，在上位機(jī)中實(shí)現(xiàn)數(shù)據(jù)存儲(chǔ)和圖形化界面顯示，從而實(shí)現(xiàn)輸油管道溫度壓力參數(shù)的實(shí)時(shí)監(jiān)測(cè)和異常報(bào)警。經(jīng)實(shí)驗(yàn)證明，該系統(tǒng)的12位數(shù)據(jù)采集精度滿足設(shè)計(jì)要求，漏碼率小于1%，正常工作時(shí)間超過(guò)5個(gè)月，能實(shí)時(shí)有效地監(jiān)測(cè)輸油管道的溫度壓力參數(shù)，節(jié)省大量人工成本，有效預(yù)防管道參數(shù)異常造成的經(jīng)濟(jì)損失和環(huán)境污染。
Abstract:
In order to solve the problems on real-time monitoring of pipeline temperature and pressure parameters， the ultra-low power remote pipeline temperature and pressure monitoring system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection， the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU， the GPRS was used by the RTU to transmit data to the PC host computer， and the data was stored and displayed in the PC host computer， so the real-time monitoring and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time， it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
為了在工業(yè)生產(chǎn)及過(guò)程控制中準(zhǔn)確測(cè)量溫度，設(shè)計(jì)了一種基于低功耗MSP430單片機(jī)的數(shù)字溫度計(jì)。整個(gè)系統(tǒng)通過(guò)單片機(jī)MSP430F1121A控制DS18B20讀取溫度，采用數(shù)碼管顯示，溫度傳感器DS18B20與單片機(jī)之間通過(guò)串口進(jìn)行數(shù)據(jù)傳輸。MSP430系列單片機(jī)具有超低功耗，且外圍的整合性高，DS18B20只需一個(gè)端口即可實(shí)現(xiàn)數(shù)據(jù)通信，連接方便。通過(guò)多次實(shí)驗(yàn)證明，該系統(tǒng)的測(cè)試結(jié)果與實(shí)際環(huán)境溫度一致，除了具有接口電路簡(jiǎn)單、測(cè)量精度高、誤差小、可靠性高等特點(diǎn)外，其低成本、低功耗的特點(diǎn)使其擁有更廣闊的應(yīng)用前景。
Abstract:
In order to obtain accurate measuring temperature in industrial production and process control， a digital thermometer based on MSP430 MCU is designed. The system uses MSP430F1121A MCU to control DS18B20， and gets the temperature data， which is displayed on the LED. The temperature sensor DS18B20 and MCU transmit data through serial communication. MSP430 series has ultra-low power and high integration， DS18B20 only needs one port to achieve data communication. Through many experimental results prove， this system is consistent with actual environment temperature. The system has characteristics of interface circuit simple， high measuring accuracy， minor error， high reliability， besides， the characteristics of low cost and low power make it having vaster application prospect.
