【正文】
沖能驅(qū)動(dòng) 4 個(gè) TTL 邏輯門(mén)電路。當(dāng)對(duì) P1 口寫(xiě) 1 時(shí),它們被內(nèi)部的上拉電阻拉升為高電平,此時(shí)可以作為輸入端使用。程序校驗(yàn)時(shí)需要外接上拉電阻。當(dāng)對(duì) 0端口寫(xiě)入 1 時(shí),可以作 為高阻抗輸入端使用。 引腳說(shuō)明: 秒信號(hào)結(jié)束時(shí)閘門(mén)關(guān)閉,計(jì)數(shù)器停止計(jì)數(shù)。若在一定時(shí)間間隔 T 內(nèi)測(cè)得這個(gè)周期性信號(hào)的 重復(fù)變化次數(shù) N,則其頻率可表示為 f=N/T。 1 課程設(shè)計(jì)概述 課程設(shè)計(jì)題目 設(shè)計(jì)一個(gè)基于 51 單片機(jī)的數(shù)字頻率計(jì),要求可以測(cè)量 1Hz~100KHz 的頻率信號(hào), 要有波形的放大與整形部分, 并用 LCD1602 顯示出來(lái)。 附 錄 ........................................................................................................ 13 程序清單 ..................................................................................................... 13 3 引言 本應(yīng)用系統(tǒng)設(shè)計(jì)的目的是通過(guò)在《 單片機(jī)原理與接口技術(shù) 》課程學(xué)習(xí)的知識(shí),以及查閱相關(guān)資料,培養(yǎng)一種自學(xué)及動(dòng)手實(shí)踐的能力。 主要儀器設(shè)備 ...................................................... 3 基本設(shè)計(jì)原理 ...................................................... 3 2 硬件 電路 設(shè)計(jì) ............................................................ 錯(cuò)誤 !未定義書(shū)簽。用 STC89C52 單片機(jī)實(shí)現(xiàn) 自動(dòng)測(cè)量功能。它的基本功能是測(cè)量正弦信號(hào),方波信號(hào)及其他各種單位時(shí)間內(nèi)變化的物理量。 它是一種用十進(jìn)制數(shù)字顯示被測(cè)信號(hào)頻率的數(shù)字測(cè)量?jī)x器。測(cè)量范圍從 1Hz— 100kHz 的正弦波、方波、三角波等多種幅度寬的信號(hào)。 關(guān)鍵詞 :數(shù)字頻率計(jì)、信號(hào)、 STC89C52 單片機(jī) 、 LCD1602 Abstract Digital frequency meter is the puter, munications equipment, audio, video and other essential areas of research and production of measuring instruments. It is a decimal figures show the number of the measured signal frequency measuring instruments. Its basic function is to measure the sinusoidal signal, square wave signals and other physical changes in unit time. During the simulation, digital circuit design, installation, missioning process, due to the use of decimal numbers show that the rapid measurement, high precision, intuitive display, often use the frequency meter. This digital frequency meter will use timing, counting methods for measuring the frequency of a 1602A LCD monitor with dynamic display of 6 digits. Measuring range from 1Hz100kHz sine wave, square wave, triangle wave, and other wide range of signals. MCU with STC89C52 automatic measurement function. The basic design principle is the direct use of the decimal figures show the measured frequency of a measuring device. It is the method to measure the cycle sine wave, square wave, triangle wave frequency signal to automatically measure and display the result. Keywords: Digital Fequency Meter, Signal, STC89C52 SCM、 LCD1602 2 引言 .................................