Microchip 單片機(jī)的速度和復(fù)雜性已經(jīng)到達(dá)足以要 求降低電源電壓的程度,并正在向 5V 電源電壓以 下轉(zhuǎn)換。但問題是絕大多數(shù)接口電路仍然是為 5V 電源而設(shè)計(jì)的。這就意味著,作為設(shè)計(jì)人員,我們 現(xiàn)在面臨著連接 3.3V 和 5V 系統(tǒng)的任務(wù)。此外, 這個(gè)任務(wù)不僅包括邏輯電平轉(zhuǎn)換,同時(shí)還包括為 3.3V 系統(tǒng)供電、轉(zhuǎn)換模擬信號(hào)使之跨越 3.3V/5V 的 障礙。 技巧和訣竅 DS41285A_CN 第 2 頁 . 2006 Microchip Technology Inc. 本 《技巧和訣竅》提供了一些電源供電組件、數(shù) 字電平轉(zhuǎn)換組件甚至模擬轉(zhuǎn)換組件,以解決所面臨 的挑戰(zhàn)。全書對(duì)每種轉(zhuǎn)換均給出了多種選擇方案, 從單片 (All-in-One)接口器件到低成本的分立解 決方案都有涉及。簡而言之,無論導(dǎo)致轉(zhuǎn)換的原因 是復(fù)雜性、成本還是尺寸,設(shè)計(jì)人員處理 3.3V 挑 戰(zhàn)可能需要的全部組件均在本文有所討論。
標(biāo)簽: 單片機(jī) 電平互聯(lián)
上傳時(shí)間: 2013-10-30
上傳用戶:wqxstar
針對(duì)煤礦井下調(diào)度及緊急救援系統(tǒng)的需求,以DTMF編解碼模塊為核心,設(shè)計(jì)了具有自動(dòng)撥號(hào)功能的新型電話系統(tǒng)。該系統(tǒng)利用MT8880對(duì)DTMF信號(hào)的編解碼功能實(shí)現(xiàn)一鍵撥號(hào)和遠(yuǎn)程設(shè)置,通過檢測振鈴和忙音信號(hào),完成自動(dòng)摘機(jī)和掛機(jī)過程,配合AGC等外圍電路達(dá)到話音清晰流暢的效果。 Abstract: To meet the demand for mine scheduling and emergency rescue system, with using DTMF signal codec as the core, a new telephone system was designed with automatic dialing function. In the system, the DTMF signal encoding and decoding function of MT8880 was used to achieve one-touch dialing and remote setting. The circuit detects the ringing and busy signal, and then completes automatic off-hook and hangup. With AGC(Automatic Gain Control) and other peripheral circuits, the voice was regulated to a clear and smooth effect.
標(biāo)簽: 8880 MT 撥號(hào)電話 系統(tǒng)設(shè)計(jì)
上傳時(shí)間: 2014-11-18
上傳用戶:ly1994
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,并能將測量結(jié)果通過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.
上傳時(shí)間: 2013-12-11
上傳用戶:jasonheung
介紹一種多功能音樂播放器,它是以AT89S52單片機(jī)為核心,并輔有一些外圍器件,采用匯編語言編寫程序,實(shí)現(xiàn)多功能音樂播放,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.
上傳時(shí)間: 2013-11-18
上傳用戶:xiaodu1124
對(duì)于傳統(tǒng)的跑步機(jī)無法聯(lián)機(jī)組網(wǎng),保存歷史數(shù)據(jù),實(shí)時(shí)調(diào)試等問題,介紹了一個(gè)由多臺(tái)跑步機(jī)通過RS-232串行總線與上位機(jī)相連組成的跑步機(jī)聯(lián)網(wǎng)系統(tǒng)。系統(tǒng)采用W77E58作為下位機(jī)核心控制器件,它具有雙串行通訊端口,其中一個(gè)串口用于與變頻器通訊,另一個(gè)串口則與上位機(jī)相連,構(gòu)成跑步機(jī)網(wǎng)絡(luò)。 Abstract: The traditional running machine can not be connected to a network, saving historical data, real time debug etc.In this paper,a new network system which is composed of running machines connected by a RS-232 communication bus is introduced.In the system,W77E58 is used as a core control unit.W77E58 has two serial ports,one is connected to the inverter and the other is connected to the PC. Thus a network appears.
標(biāo)簽: W77E58 跑步機(jī) 聯(lián)網(wǎng)系統(tǒng)
上傳時(shí)間: 2014-12-27
上傳用戶:哇哇哇哇哇
介紹了基于單片機(jī)C8051F020的通用串口適配器的設(shè)計(jì)與實(shí)現(xiàn)方法,即由單片機(jī)控制的智能化一對(duì)多口收發(fā)信號(hào)轉(zhuǎn)換器。通過采用C51對(duì)單片機(jī)進(jìn)行編程,控制與RS-232(標(biāo)準(zhǔn)RS-232電平)、RS232(TTL電平)、RS-422接口的數(shù)據(jù)通信;采用C++ Builder作為開發(fā)平臺(tái),通過RS-232接口實(shí)現(xiàn)上位機(jī)對(duì)適配器各個(gè)通信端口的控制。 Abstract: Design and realization of a universal serial port adapter based on the MCU C8051F020 are introduced.The adapter is an intelligent one-to-more receiving and transmitting signal converter controlled by the MCU. By programming the MCU with the language C51,MCU control data communication between the MCU and RS-232(RS-232 level),RS-232(TTL level),RS-422 port; Using C++ Builder as the development plane, by one RS232 port, the upper PC can control each of the communication port of the adapter.
上傳時(shí)間: 2013-11-19
上傳用戶:hebanlian
為了在工業(yè)生產(chǎn)及過程控制中準(zhǔn)確測量溫度,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。通過多次實(shí)驗(yàn)證明,該系統(tǒng)的測試結(jié)果與實(shí)際環(huán)境溫度一致,除了具有接口電路簡單、測量精度高、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.
上傳時(shí)間: 2013-10-16
上傳用戶:wettetw
針對(duì)當(dāng)前安檢力學(xué)試驗(yàn)機(jī)所能完成的試驗(yàn)種類單一、自動(dòng)化程度低等問題,提出一種以ATmega128單片機(jī)為核心控制器的安檢力學(xué)試驗(yàn)機(jī)的設(shè)計(jì)。詳細(xì)闡述了該安檢力學(xué)試驗(yàn)機(jī)各個(gè)組成部分的設(shè)計(jì)原理和方案,并且給出了各部分的軟件設(shè)計(jì)思想和操作流程。經(jīng)過大量測試試驗(yàn)表明:設(shè)計(jì)的安檢力學(xué)試驗(yàn)機(jī)可以完成多達(dá)十余種的力學(xué)安檢試驗(yàn),完全符合相關(guān)國家標(biāo)準(zhǔn),并且具有數(shù)據(jù)采集精度高、傳輸速度快、操作安全簡便等特點(diǎn),實(shí)現(xiàn)了安檢設(shè)備的多功能化、數(shù)字化和自動(dòng)化。 Abstract: Currently, many mechanical security testing machines have only one function. The degree of automation of them is low. To solve those problems, a new kind of mechanical security testing machine, using ATmega128 micro-controller as its core controller, has been advanced. It describes the components of the machine. The principles and the scheme in the designing processes are presented in detail, and the software architecture and the operation processes of each part are given. After having done many testing, we have reached the following conclusions: the mechanical security testing machine presented can do over ten mechanical security tests complying with related national standards. It has high data acquisition accuracy and high transmission speed. The operation of the machine is simple and safe. In general, this machine is a multi-functional, highly automatic, digitalized security testing device.
標(biāo)簽: ATmega 128 安檢 試驗(yàn)機(jī)
上傳時(shí)間: 2013-11-05
上傳用戶:a67818601
Information in this document is subject to change without notice and does notrepresent a commitment on the part of the manufacturer. The software describedin this document is furnished under license agreement or nondisclosureagreement and may be used or copied only in accordance with the terms of theagreement. It is against the law to copy the software on any medium except asspecifically allowed in the license or nondisclosure agreement. The purchasermay make one copy of the software for backup purposes. No part of this manualmay be reproduced or transmitted in any form or by any means, electronic ormechanical, including photocopying, recording, or information storage andretrieval systems, for any purpose other than for the purchaser’s personal use,without written permission.
上傳時(shí)間: 2014-12-27
上傳用戶:Tracey
The bootloader is stored in the internal boot ROM memory (system memory) of STM32devices. It is programmed by ST during production. Its main task is to download theapplication program to the internal Flash memory through one of the available serialperipherals (USART, CAN, USB, etc.). A communication protocol is defined for each serialinterface, with a compatible command set and sequences
標(biāo)簽: STM 32 啟動(dòng)代碼
上傳時(shí)間: 2014-09-06
上傳用戶:417313137
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