計(jì)算機(jī)部件要具有通用性,適應(yīng)不同系統(tǒng)與不同用戶的需求,設(shè)計(jì)必須模塊化。計(jì)算機(jī)部件產(chǎn)品(模塊)供應(yīng)出現(xiàn)多元化。模塊之間的聯(lián)接關(guān)系要標(biāo)準(zhǔn)化,使模塊具有通用性。模塊設(shè)計(jì)必須基于一種大多數(shù)廠商認(rèn)可的模塊聯(lián)接關(guān)系,即一種總線標(biāo)準(zhǔn)。總線的標(biāo)準(zhǔn)總線是一類信號(hào)線的集合是模塊間傳輸信息的公共通道,通過它,計(jì)算機(jī)各部件間可進(jìn)行各種數(shù)據(jù)和命令的傳送。為使不同供應(yīng)商的產(chǎn)品間能夠互換,給用戶更多的選擇,總線的技術(shù)規(guī)范要標(biāo)準(zhǔn)化。總線的標(biāo)準(zhǔn)制定要經(jīng)周密考慮,要有嚴(yán)格的規(guī)定。總線標(biāo)準(zhǔn)(技術(shù)規(guī)范)包括以下幾部分:機(jī)械結(jié)構(gòu)規(guī)范:模塊尺寸、總線插頭、總線接插件以及按裝尺寸均有統(tǒng)一規(guī)定。功能規(guī)范:總線每條信號(hào)線(引腳的名稱)、功能以及工作過程要有統(tǒng)一規(guī)定。電氣規(guī)范:總線每條信號(hào)線的有效電平、動(dòng)態(tài)轉(zhuǎn)換時(shí)間、負(fù)載能力等。總線的發(fā)展情況S-100總線:產(chǎn)生于1975年,第一個(gè)標(biāo)準(zhǔn)化總線,為微計(jì)算機(jī)技術(shù)發(fā)展起到了推動(dòng)作用。IBM-PC個(gè)人計(jì)算機(jī)采用總線結(jié)構(gòu)(Industry Standard Architecture, ISA)并成為工業(yè)化的標(biāo)準(zhǔn)。先后出現(xiàn)8位ISA總線、16位ISA總線以及后來兼容廠商推出的EISA(Extended ISA)32位ISA總線。為了適應(yīng)微處理器性能的提高及I/O模塊更高吞吐率的要求,出現(xiàn)了VL-Bus(VESA Local Bus)和PCI(Peripheral Component Interconnect,PCI)總線。適合小型化要求的PCMCIA(Personal Computer Memory Card International Association)總線,用于筆記本計(jì)算機(jī)的功能擴(kuò)展。總線的指標(biāo)計(jì)算機(jī)主機(jī)性能迅速提高,各功能模塊性能也要相應(yīng)提高,這對(duì)總線性能提出更高的要求。總線主要技術(shù)指標(biāo)有幾方面:總線寬度:一次操作可以傳輸?shù)臄?shù)據(jù)位數(shù),如S100為8位,ISA為16位,EISA為32位,PCI-2可達(dá)64位。總線寬度不會(huì)超過微處理器外部數(shù)據(jù)總線的寬度。總數(shù)工作頻率:總線信號(hào)中有一個(gè)CLK時(shí)鐘,CLK越高每秒鐘傳輸?shù)臄?shù)據(jù)量越大。ISA、EISA為8MHz,PCI為33.3MHz, PCI-2可達(dá)達(dá)66.6MHz。單個(gè)數(shù)據(jù)傳輸周期:不同的傳輸方式,每個(gè)數(shù)據(jù)傳輸所用CLK周期數(shù)不同。ISA要2個(gè),PCI用1個(gè)CLK周期。這決定總線最高數(shù)據(jù)傳輸率。5. 總線的分類與層次系統(tǒng)總線:是微處理器芯片對(duì)外引線信號(hào)的延伸或映射,是微處理器與片外存儲(chǔ)器及I/0接口傳輸信息的通路。系統(tǒng)總線信號(hào)按功能可分為三類:地址總線(Where):指出數(shù)據(jù)的來源與去向。地址總線的位數(shù)決定了存儲(chǔ)空間的大小。系統(tǒng)總線:數(shù)據(jù)總線(What)提供模塊間傳輸數(shù)據(jù)的路徑,數(shù)據(jù)總線的位數(shù)決定微處理器結(jié)構(gòu)的復(fù)雜度及總體性能。控制總線(When):提供系統(tǒng)操作所必需的控制信號(hào),對(duì)操作過程進(jìn)行控制與定時(shí)。擴(kuò)充總線:亦稱設(shè)備總線,用于系統(tǒng)I/O擴(kuò)充。與系統(tǒng)總線工作頻率不同,經(jīng)接口電路對(duì)系統(tǒng)總統(tǒng)信號(hào)緩沖、變換、隔離,進(jìn)行不同層次的操作(ISA、EISA、MCA)局部總線:擴(kuò)充總線不能滿足高性能設(shè)備(圖形、視頻、網(wǎng)絡(luò))接口的要求,在系統(tǒng)總線與擴(kuò)充總線之間插入一層總線。由于它經(jīng)橋接器與系統(tǒng)總線直接相連,因此稱之為局部總線(PCI)。
標(biāo)簽: 微型計(jì)算機(jī) 總線
上傳時(shí)間: 2013-11-09
上傳用戶:nshark
基于單片機(jī)的汽車多功能報(bào)警系統(tǒng)設(shè)計(jì)The Design of Automobile Multi-function AlarmingBased on Single Chip Computer劉法治趙明富寧睡達(dá)(河 南 科 技 學(xué) 院 ,新 鄉(xiāng) 453 00 3)摘要介紹了一種基于單片機(jī)控制的汽車多功能報(bào)警系統(tǒng),它能對(duì)汽車的潤(rùn)滑系統(tǒng)油壓、制動(dòng)系統(tǒng)氣壓、冷卻系統(tǒng)溫度、輪胎欠壓及防盜進(jìn)行自動(dòng)檢測(cè),并在發(fā)現(xiàn)異常情況時(shí),發(fā)出聲光報(bào)警。闡述了該報(bào)警系統(tǒng)的硬件組成及軟件設(shè)計(jì)方法。關(guān)鍵詞單片機(jī)傳感器數(shù)模轉(zhuǎn)換報(bào)警Abstract Am ulti-fimctiona utomobilea larnungs ystemb asedo ns inglec hipc omputerco ntorlis in torducedin th isp aper.Th eo ilpr essuero flu bricatesystem, air pressure of braking system, temperature of cooling system, under pressure of tyre and guard against theft, detected automaticaly場(chǎng)thesystem. Audio and visual alarms wil be provided under abnormal conditions廠The hardware composition and software design of the system, described.Keywords Singlec hipc omputer Sensor Digital-t-oanaloguec onversion Alarmin 汽車多功能報(bào)苦器硬件系統(tǒng)設(shè)計(jì)根據(jù) 系 統(tǒng) 實(shí)際需要和產(chǎn)品性價(jià)比,選用ATMEL公司新生產(chǎn)的采用CMOs工藝的低功耗、高性能8位單片機(jī)AT89S52作為系統(tǒng)的控制器。AT89S52的片內(nèi)有8k Bytes LSP Flash閃爍存儲(chǔ)器,可進(jìn)行100(〕次寫、擦除操作;256Bytes內(nèi)部數(shù)據(jù)存儲(chǔ)器(RAM);3 2 根可編程輸N輸出線;2個(gè)可編程全雙工串行通道;看門狗(WTD)電路等。系統(tǒng)由傳感器、單片機(jī)、模數(shù)轉(zhuǎn)換器、無線信號(hào)發(fā)射電路、指示燈驅(qū)動(dòng)電路、聲光報(bào)警驅(qū)動(dòng)電KD一9563,發(fā)出三聲二閃光。并觸發(fā)一個(gè)高電平,驅(qū)動(dòng)無線信號(hào)發(fā)射電路。
標(biāo)簽: 單片機(jī) 汽車 多功能 報(bào)警
上傳時(shí)間: 2013-11-09
上傳用戶:gxmm
一種基于ST62單片機(jī)的稱重顯示控制器A Weighing Display Controller Based on ST62 Single Chip Computer祛 FA(上海時(shí)博飛奧控制系統(tǒng)有限公司,上海201100)摘要在介紹了基于ST62單片機(jī)的基礎(chǔ)上,詳細(xì)描述了稱重顯控制器的硬件設(shè)計(jì)和軟件設(shè)計(jì)思路。該控制器結(jié)構(gòu)簡(jiǎn)單、操作方便、抗擾能力強(qiáng)等優(yōu)點(diǎn);具有較好的推廣應(yīng)用價(jià)值。關(guān)鍵詞稱重顯示控制儀ST62單片機(jī)硬件設(shè)計(jì)軟件設(shè)計(jì)Abstract Ont heb asiso fin torductiono fST 62s inglec hipc omputer,th ed esignc oncrptof h ardwarea nds oftwarefo rw eighingd isplayc ontorleris d escrbed.The controler features simple structure, ease operation, powerful capability of anti-interference, etc.,it is wealth to be promoted into practicalapplicationsKeywords We妙噸display0 引言ST62s inglec hip Hardwared esign Softwaer design備 份 振 蕩器,振蕩器保護(hù)電路,上電復(fù)位及低壓檢測(cè)復(fù)稱 重 顯 示控制器是一種具有數(shù)字顯示、開關(guān)量輸出、定值控制和通信功能的以微機(jī)為操作核心的稱重控制裝置。它是電子衡器的重要基礎(chǔ)部件,直接影響電子衡器及電子稱重系統(tǒng)的功能和性能。與合適的傳感器及承重傳力復(fù)位系統(tǒng)組合可組成配料秤、料斗秤、定值秤、平臺(tái)秤、汽車秤等,廣泛應(yīng)用于電力、化工、建筑、冶金、交通運(yùn)輸、食品、軍工等部門,是進(jìn)行自動(dòng)稱重配料控制和生產(chǎn)過程自動(dòng)化必不可少的重要檢測(cè)、控制裝置。隨著 稱 重 計(jì)量自動(dòng)化水平的提高,對(duì)稱重顯示控制器的要求也越來越高。為實(shí)現(xiàn)低漂移、高穩(wěn)定,本控制器采用低漂移、高增益放大器AD620和高分辨率的A/D轉(zhuǎn)換器CS5550。為提高穩(wěn)定性和可靠性,采用集成度高的、抗干擾能力強(qiáng)的ST62單片機(jī)。
上傳時(shí)間: 2013-10-29
上傳用戶:釣鰲牧馬
單片機(jī)系統(tǒng)“PC”失控的軟件措施Software Measure of GettingO uto fC ontrolfo r“PC"in S ingleC hipC omputerS ystem謐 加 春 王 曉 基 雷 小 華(江 西 理 工 大 學(xué)機(jī) 電 工 程 學(xué) 院 ,贛 州 34 10 00)摘要單片機(jī)系統(tǒng)在實(shí)際工業(yè)現(xiàn)場(chǎng)中可能遇到各種干擾和自身的隨機(jī)性故障。現(xiàn)場(chǎng)惡劣的環(huán)境有可能使計(jì)算機(jī)系統(tǒng)發(fā)生異常,計(jì)算機(jī)程序指針“PC”失控就是常見的故障之一,如果發(fā)生“PC”失控,將導(dǎo)致CPI工作混亂,釀成嚴(yán)重的事故。研究了“PC”失控的原因,并指出軟件抗干擾的幾種方法,有效保證單片機(jī)系統(tǒng)的正常工作。關(guān)鍵詞單片機(jī)“PC”失控抗干擾Abstract Inp racticalin dustrialfi elds,th ereis v ariousin terferencea fectingo perationo fsi nglec hipc omputersy stemsa ndt hec omputersy stems。fac噸random faults飾themselves. It is very common that the severe environment makes the computer systems abnormal. The program counter "PC"gettingo utof co ntorlis on eo fth ec ommonfa ults.If th isoc curs,C PUw ouldb eru nningo utof or deran din torducesse riousan cient.T hec ausesof " PC"geting out of control, studied in this paper and some countermeasures of anti-interference師software are given to ensure single chip computer systemworking properly.Keywords Single。飾computer Porgramc ounter"P C" Anti-interfeernc 在設(shè) 計(jì) 和 開發(fā)單片機(jī)系統(tǒng)時(shí),一般難以周全地預(yù)計(jì)單片機(jī)系統(tǒng)在實(shí)際工業(yè)現(xiàn)場(chǎng)中可能遇到的各種干擾和自身的隨機(jī)性故障。因此,除了采取防止和抑制干擾的各項(xiàng)措施外,還應(yīng)該借助于軟件措施克服某些干擾,系統(tǒng)還應(yīng)具備迅速自行恢復(fù)的能力。本文介紹的應(yīng)對(duì)單片機(jī)系統(tǒng)PC失控的軟件措施,設(shè)計(jì)靈活,節(jié)省硬件資源,能保證測(cè)控系統(tǒng)長(zhǎng)期可靠地運(yùn)行。MC S- 5 1單片機(jī)以其優(yōu)良的性能價(jià)格比大量應(yīng)用于工業(yè)現(xiàn)場(chǎng)測(cè)試和控制領(lǐng)域。但是,現(xiàn)場(chǎng)惡劣的環(huán)境有可能使計(jì)算機(jī)系統(tǒng)發(fā)生異常,計(jì)算機(jī)程序指針PC失控就是常見的故障之一,一旦發(fā)生PC“走飛”,計(jì)算機(jī)系統(tǒng)就會(huì)出現(xiàn)工作混亂,釀成嚴(yán)重的事故。為 了 在 CP 失控時(shí)盡量減少由此帶來的不利影響,并盡快使系統(tǒng)恢復(fù)正常,需要采取一定的軟件措施和硬件措施。常見的硬件措施有“看門狗”電路。軟件措施設(shè)置的前提條件是:①在干擾作用下,微機(jī)系統(tǒng)硬件部分不會(huì)受到任何損壞,或者損壞部分設(shè)置有監(jiān)測(cè)狀態(tài)可供查詢;②程序區(qū)不會(huì)受到干擾侵害。單片機(jī)系統(tǒng)的程序和表格以及重要的參數(shù)均設(shè)置在ROM區(qū),不會(huì)因干擾的侵人而改變;③ RAM區(qū)中的重要數(shù)據(jù)不會(huì)被破壞,或者雖然被破壞,但是可以重新建立。
標(biāo)簽: 單片機(jī)系統(tǒng) 軟件
上傳時(shí)間: 2013-11-02
上傳用戶:bhqrd30
The PL2303 USB to Serial adapter is your smart and convenient accessory forconnecting RS-232 serial devices to your USB-equipped Windows host computer. Itprovides a bridge connection with a standard DB 9-pin male serial port connector inone end and a standard Type-A USB plug connector on the other end. You simplyattach the serial device onto the serial port of the cable and plug the USB connectorinto your PC USB port. It allows a simple and easy way of adding serial connectionsto your PC without having to go thru inserting a serial card and traditional portconfiguration.This USB to Serial adapter is ideal for connecting modems, cellular phones, PDAs,digital cameras, card readers and other serial devices to your computer. It providesserial connections up to 1Mbps of data transfer rate. And since USB does not requireany IRQ resource, more devices can be attached to the system without the previoushassles of device and resource conflicts.Finally, the PL-2303 USB to Serial adapter is a fully USB Specification compliantdevice and therefore supports advanced power management such as suspend andresume operations as well as remote wakeup. The PL-2303 USB Serial cable adapteris designed to work on all Windows operating systems.
標(biāo)簽: Adapter Serial 2303 USB
上傳時(shí)間: 2013-11-01
上傳用戶:ghostparker
(Portmon is an application that lets you monitor serial and parallel activity on your local system, or any computer on the network that you can reach via TCP/IP. It is the most powerful tool available for tracking down port-related configuration problems and analyzing application port usage.)
上傳時(shí)間: 2013-11-07
上傳用戶:1412904892
針對(duì)運(yùn)行中火車測(cè)速運(yùn)用多普勒效應(yīng)采用DSP 設(shè)計(jì)雷達(dá)測(cè)速系統(tǒng)并闡述了其基本設(shè)計(jì)思想與工作原理給出系統(tǒng)硬件軟件設(shè)計(jì)結(jié)構(gòu)和原理圖改善了原有光電測(cè)速精度提高了系統(tǒng)工作穩(wěn)定性和可靠性經(jīng)實(shí)驗(yàn)證明DSP 采集板工作穩(wěn)定測(cè)速效果好關(guān)鍵詞DSP; 雷達(dá)測(cè)速; 多普勒效應(yīng) On Board DSP-Based Radar Speed Measurement System TANG Wei, SUN Zhi-fang, CHEN Quan (Dept.of computer Science,Yangtze University,Jingzhou 434023,China)Abstract: This paper presents a DSP-based train speed measurement by using Doppler radar. The structure of the system is introduced.The hardware and software are also discussed.Key words: DSP; rader speed measurement; doppler principle
標(biāo)簽: DSP 車載 系統(tǒng)設(shè)計(jì) 雷達(dá)測(cè)速
上傳時(shí)間: 2013-10-27
上傳用戶:003030
This application note describes how to build a system that can be used for determining theoptimal phase shift for a Double Data Rate (DDR) memory feedback clock. In this system, theDDR memory is controlled by a controller that attaches to either the OPB or PLB and is used inan embedded microprocessor application. This reference system also uses a DCM that isconfigured so that the phase of its output clock can be changed while the system is running anda GPIO core that controls that phase shift. The GPIO output is controlled by a softwareapplication that can be run on a PowerPC® 405 or Microblaze™ microprocessor.
上傳時(shí)間: 2013-10-15
上傳用戶:euroford
This application note covers the design considerations of a system using the performance features of the LogiCORE™ IP Advanced eXtensible Interface (AXI) Interconnect core. The design focuses on high system throughput through the AXI Interconnect core with F MAX and area optimizations in certain portions of the design. The design uses five AXI video direct memory access (VDMA) engines to simultaneously move 10 streams (five transmit video streams and five receive video streams), each in 1920 x 1080p format, 60 Hz refresh rate, and up to 32 data bits per pixel. Each VDMA is driven from a video test pattern generator (TPG) with a video timing controller (VTC) block to set up the necessary video timing signals. Data read by each AXI VDMA is sent to a common on-screen display (OSD) core capable of multiplexing or overlaying multiple video streams to a single output video stream. The output of the OSD core drives the DVI video display interface on the board. Performance monitor blocks are added to capture performance data. All 10 video streams moved by the AXI VDMA blocks are buffered through a shared DDR3 SDRAM memory and are controlled by a MicroBlaze™ processor. The reference system is targeted for the Virtex-6 XC6VLX240TFF1156-1 FPGA on the Xilinx® ML605 Rev D evaluation board
標(biāo)簽: XAPP 740 AXI 互聯(lián)
上傳時(shí)間: 2013-11-14
上傳用戶:fdmpy
1 Communication Protocol (Computer as master) The communication protocol describes here allows your computer to access 4096 internal registers (W0000-W4095) and 1024 internal relays (B0000-B1023) in the Workstation.. 1.1 Request Message Format Request message is a command message to be sent from the computer to the Workstation. The data structure of request message is shown below. Note that numbers are always in hexadecimal form and converted into ASCII characters. For example, Workstation unit number 14 will appear in the message as character 0(30h) followed by character E(45h); a BCC of 5Ah will appear in the message as character 5(35h) followed by character A(41h).
上傳時(shí)間: 2013-10-28
上傳用戶:cxl274287265
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