【正文】 較器 輸入電壓 輸入數(shù)字量 基于單片機(jī)的簡(jiǎn)易數(shù)字電壓表的設(shè)計(jì) 4 接接口，片內(nèi)帶有鎖存功能的 8 路模擬多路開(kāi)關(guān)，可以對(duì) 8 路 05V 輸入模擬電壓信號(hào)分時(shí)進(jìn)行轉(zhuǎn)換，由于 ADC0808 設(shè) 計(jì)時(shí)考慮到若干種模 /數(shù)變換技術(shù)的長(zhǎng)處，所以該芯片非常適應(yīng)于過(guò)程控制，微控制器輸入通道的接口電路，智能儀器和機(jī)床控制等領(lǐng)域 [5]。 一個(gè) n 位的逐次逼近型 A/D 轉(zhuǎn)換器只需要比較 n 次，轉(zhuǎn)換時(shí)間只取決于位數(shù)和時(shí)鐘周期，逐次逼近型 A/D 轉(zhuǎn)換器轉(zhuǎn)換速度快，因而在實(shí)際中廣泛使用 [1]。硬件電路設(shè)計(jì)框圖 如圖 1所示。 ⑶ 電壓顯示采用 4 位一體的 LED 數(shù)碼管。 ⑶ 電壓顯示用 4位一體的 LED 數(shù)碼管顯示，至少能夠顯示兩位小數(shù)。 本文是以簡(jiǎn)易數(shù)字直流電壓表的設(shè)計(jì)為研究?jī)?nèi)容，本系統(tǒng)主要包括三大模塊：轉(zhuǎn) 換模塊、數(shù)據(jù)處理模塊 及顯示模塊。目前，由各種單片機(jī)和 A/D 轉(zhuǎn)換器構(gòu)成的數(shù)字電壓表作全面深入的了解是很有必要的。 傳統(tǒng)的指針式刻度電壓表功能單一，進(jìn)度低，容易引起視差和視覺(jué)疲勞，因而不 能滿足數(shù)字化時(shí)代的需要。 基于單片機(jī)的簡(jiǎn)易數(shù)字電壓表的設(shè)計(jì) III ADC0808 基于單片機(jī)的簡(jiǎn)易數(shù)字電壓表的設(shè)計(jì) IV 目 錄 1 引言 .......................................................................................... 1 2 設(shè)計(jì)總體方案 .......................................................................... 2 設(shè)計(jì)要求 ........................................................................... 2 設(shè)計(jì)思路 .......................................................................... 2 設(shè)計(jì)方案 .......................................................................... 2 3 硬件 電路設(shè)計(jì) .......................................................................... 3 A/D 轉(zhuǎn)換模塊 ................................................................ 3 單片機(jī)系統(tǒng) .................................................................... 7 復(fù)位電路和時(shí)鐘電路 .................................................... 9 LED 顯示系統(tǒng)設(shè)計(jì) ..................................................... 10 總體電路設(shè)計(jì) .............................................................. 13 4 程序設(shè)計(jì) ................................................................................ 15 程序設(shè)計(jì)總方案 .......................................................... 15 系統(tǒng)子程序設(shè)計(jì) .......................................................... 15 5 仿真 ...................................................................................... 17 軟件調(diào)試 ...................................................................... 17 顯示結(jié) 果及誤差分析 .................................................. 17 結(jié) 論 .......................................................................................... 20 參考文獻(xiàn) .................................................................................... 21 附錄 程序代碼 .......................................................................... 22 基于單片機(jī)的簡(jiǎn)易數(shù)字電壓表的設(shè)計(jì) V 致謝 ........................................................................................... 25 基于單片機(jī)的簡(jiǎn)易數(shù)字電壓表的設(shè)計(jì) 1 1 引言 在電量的測(cè)量中，電壓、電流和頻率是最基本的三個(gè)被測(cè)量，其中電壓量的測(cè)量最為經(jīng)常。 關(guān)鍵詞 單片機(jī)； 數(shù)字電壓表 ； A/D 轉(zhuǎn)換； AT89C51； ADC0809 基于單片機(jī)的簡(jiǎn)易數(shù)字電壓表的設(shè)計(jì) II Design of Simple Digital Voltmeter Based on Singlechip Microcontroller Tian Mingming Abstract This paper which introduces a kind of simple digital voltmeter is based on singlechip microcontroller design. The circuit of the voltage meter is mainly consisted of three mould pieces: A/D converting mould piece, A/D converting is mainly pleted by the ADC0808, it converts the collected analog data into the digital data and transmits the oute to the manifestation controlling mould piece. Data processing is mainly pleted by the AT89C51 chip, it processes the data produced by the ADC0808 chip and generates the right manifestation codes, also transmits the codes to the manifestation controlling mould piece. Also, the AT89C51 chip controls the ADC0808 chip to work. The voltmeter features in simple electrical circuit, lower use of elements, low cost, moreover, its measuring precision and reliability. The voltmeter is capable of measuring voltage inputs from 1 route ranging from 0 to 5 volt, and displaying the measurements thou