【正文】 本科畢業(yè)設(shè)計(jì)（論文） I 單片機(jī)遠(yuǎn)程數(shù)碼顯示系統(tǒng)設(shè)計(jì) 摘 要 本文介紹了一種新型的共陰極 LED驅(qū)動(dòng)芯片 MAX7219。 MAX7219可驅(qū)動(dòng) 8位 7段共陰極 LED數(shù)碼管。本設(shè)計(jì)著重論述了該芯片的硬件特點(diǎn)和使用方法。用該芯片驅(qū)動(dòng) LED，有動(dòng)態(tài)顯示和靜態(tài)顯示兩種方式，具有硬件電路簡(jiǎn)單，軟件工作量小，顯示亮度高，不閃爍等優(yōu)點(diǎn)。 LED 數(shù)碼管的應(yīng)用已 十分廣泛，用于數(shù)碼管顯示的驅(qū)動(dòng)電路種類較多，但大致可分為靜態(tài)顯示驅(qū)動(dòng)和動(dòng)態(tài)掃描顯示驅(qū)動(dòng)兩大類別。本文所要介紹的MAX7219 芯片就是用于動(dòng)態(tài)掃描顯示驅(qū)動(dòng)的芯片。該芯片的特點(diǎn)是利用一塊芯片就能完成 8 位字?jǐn)?shù)據(jù)和 8 位線數(shù)據(jù)的驅(qū)動(dòng) ,使得電路緊湊。 7219 芯片以其功能強(qiáng)大，編程簡(jiǎn)單，控制顯示可靠，可廣泛用于工業(yè)控制器等方面的數(shù)碼顯示驅(qū)動(dòng)，比較成熟的應(yīng)用即為與單片機(jī)的結(jié)合。 多芯片級(jí)聯(lián)時(shí)，采用串行輸入輸出，可節(jié)省 CPU 的口線和接口芯片。 MAX7219 通過加在 V+和 ISET之間的一個(gè)外部電阻來控制顯示亮度，這個(gè)電阻可以是固 定的，也可以是可變電阻，另外也可以通過亮度寄存器來控制。 本文是在 51 單片機(jī)系統(tǒng)中使用專用的 LED 顯示驅(qū)動(dòng)芯片實(shí)現(xiàn) 8 位 LED 數(shù)碼管顯示，并且選擇多功能串行 LED顯示驅(qū)動(dòng)器 MAX7219。 可以對(duì)輸入的數(shù)據(jù)先進(jìn)行譯碼再驅(qū)動(dòng)輸出，也可以將輸入的數(shù)據(jù)直接驅(qū)動(dòng)。 關(guān)鍵詞 ： LED 顯示屏 ， MAX7219，單片機(jī)， AT89C51 本科畢業(yè)設(shè)計(jì)（論文） II THE DESIDN OF REMOTE DIGITAL DISPLAY SYSTEM BASED ON SCM ABSTRACT This paper introduces a new type of total cathode LED driver chip MAX7219. A single 7219 can drive eight 7segments LED. The design is focused on the hardware and software features of the chip. There are two modes of diesplay: static and dynamic. Using 7219 has many advantages, such as simple hardware, small workload of software, highbrightness display and noneblinking. By applying such techniques as single chip microputer ， work munication and long— range vision， a master／ slave distributed long— range I． ED display control system based on the bus has been developed． It can simultaneously monitor and control many LED displays distributed in different distant places and dramatically refresh their display contents. which can also be previewed on the PC． The design principle， hardware construction and software design for the said system is present． The telemunication principle and method for the multi LED display are given in detail． The application of digital LED has a very wide range. There are large types of driving circuits used in digital display. There are about two categories of display: static and dynamic. The chip MAX7219 is used in the dynamic scanning display. The features of the chip is using only one can achieve the driver of eight characters of data and eight lines. It can make the circuit pact. When there are cascaded Multichips, it can save CPU interface and lines while using serial inputout put. MAX7219 controls the display brightness in the way of increasing an external resistor between the V+ and ISET. It could be a fixed resistor, or a variable one. In 本科畢業(yè)設(shè)計(jì)（論文） III addition, it can also use brightness register. It can decode the input data and then drive the out put, can also directly drive input data. KEY WORDS： LED, MAX7219, SCM， AT89C51本科畢業(yè)設(shè)計(jì)（論文） IV 目 錄 前 言 ...............................................................................................................................1 第 1 章 LED 顯示屏簡(jiǎn)介 ..............................................................................................4 167。 LED 顯示屏的未來發(fā)展方向 ..........................................................................5 167。 LED 顯示屏介紹 ................................................................................................5 167。 LED 顯示屏的發(fā)展過程 ...................................................................................7 167。 LED 顯示屏的類型 ...........................................................................................8 167。 LED 顯示屏的控制技術(shù) ...................................................................................9 第 2 章 顯示控制和驅(qū)動(dòng)電路 ....................................................................................10 167。 LED 顯示器的工作原理 .................................................................................10 167。 LED 顯示器的顯示方式 .................................................................................12 167。 LED 的動(dòng)態(tài)顯示方法 .............................................................................12 167。 LED 的靜態(tài)顯示方法 .............................................................................13 167。 芯片介紹 ..........................................................................................................13 167。 顯示驅(qū)動(dòng)芯片的選取 .....................................................................................14 第 3 章 硬件電路 .........................................................................................................16 167。 主要器件 ..........................................................................................................16 167。 電路原理圖 ......................................................................................................16 167。 電路分析 ..........................................................................................................19 167。 時(shí)鐘電路 ..................................................................................................19 167。 復(fù)位電路 ..................................................................................................19 167。 硬件連接 ..................................................................................................19 167。 MAX7219 引腳說明 ........................................................................................20 167。 MAX7219 的工作原理 ...................................................................................22 167。 驅(qū)動(dòng)顯示屏 ......................................................................................................22 第 4 章 系統(tǒng)軟件設(shè)計(jì) .................................................................................................28 167。 MAX7219 的工作描述 ...................................................................................28 167。 流程圖 ..............................................................................................................29 本科畢業(yè)設(shè)計(jì)（論文） V 167。4 .3 程序設(shè)計(jì) ..........................................................................................................29 結(jié) 論 ..........................