北京交大單片機(jī)課程設(shè)計(jì)16×16點(diǎn)陣

1、一、設(shè)計(jì)任務(wù)書（一）實(shí)驗(yàn)?zāi)康?、了解點(diǎn)陣式LED顯示原理。2、熟悉PROTEUS軟件電路仿真的使用。3、掌握單片機(jī)與16×16點(diǎn)陣塊之間接口電路設(shè)計(jì)及編程。4、掌握74HC154芯片工作原理及與單片機(jī)的接口電路設(shè)計(jì)。（二）設(shè)計(jì)任務(wù)及要求利用已學(xué)單片機(jī)知識(shí)，根據(jù)點(diǎn)陣式LED顯示器的顯示原理，自行設(shè)計(jì)電路，進(jìn)行PROTEUS軟件仿真測(cè)試，焊接電路板，完成16×16點(diǎn)陣式LED的顯示結(jié)果。要求：在單片機(jī)的控制下點(diǎn)陣顯示屏顯示“電子設(shè)計(jì)”，顯示方式分別為單字循環(huán)顯示、左右滾動(dòng)顯示、上下滾動(dòng)顯示。二、硬件電路設(shè)計(jì)（一） 硬件電路框圖如下：圖一、16×16點(diǎn)陣顯示硬件電路圖

2、本實(shí)驗(yàn)采用以AT89C51單片機(jī)為核心芯片的驅(qū)動(dòng)電路和顯示電路來實(shí)現(xiàn)，主要由AT89C51芯片、時(shí)鐘電路、復(fù)位電路、列掃描驅(qū)動(dòng)電路(74HC154)、16×16LED點(diǎn)陣5部分組成，如圖一所示。 時(shí)鐘電路由AT89C51的18、19腳的時(shí)鐘端(XTAL1及XTAL2)以及12MHz晶振X1、電容C2、C3組成，采用片內(nèi)振蕩方式。復(fù)位電路采用簡(jiǎn)易的上電復(fù)位電路，主要由電阻R1，R2，電容C1，開關(guān)K1組成，分別接至AT89C51的RST復(fù)位輸入端。列掃描驅(qū)動(dòng)電路由74HC154芯片實(shí)現(xiàn)，其管腳及功能真值表如圖二所示。74HC154是一個(gè)4-16線譯碼器，A、B、C、D是四個(gè)輸入，Y0-

3、Y15是十六個(gè)輸出，且低電平有效。使能端口G1、G2全為低電平時(shí)，74HC154芯片方正常工作，產(chǎn)生輸出。 圖二、74HC154芯片引腳說明及功能真值表LED點(diǎn)陣顯示屏采用 16×16共256個(gè)象素的點(diǎn)陣，通過萬用表檢測(cè)發(fā)光二極管的方法測(cè)試判斷出該點(diǎn)陣的引腳分布，如圖三所示。圖三、16×16點(diǎn)陣引腳排列圖16×16點(diǎn)陣共由64個(gè)發(fā)光二極管組成，且每個(gè)發(fā)光二極管是放置在行線和列線的交叉點(diǎn)上，當(dāng)對(duì)應(yīng)的某一列置0低電平，某一行置1高電平，則相應(yīng)的二極管就亮。16×16點(diǎn)陣的列輸入為C0-C15，行輸入為A0-A15。要顯示某一個(gè)字，首先要設(shè)計(jì)該字的點(diǎn)陣字形，編

4、好行（或列）點(diǎn)陣碼，然后在單片機(jī)的控制下對(duì)點(diǎn)陣進(jìn)行逐行（或列）掃描。本實(shí)驗(yàn)采用的是列掃描方式控制字符的顯示。若將LED點(diǎn)陣的行列端口全部直接接入 AT89C51單片機(jī)，則需要使用32條IO口，這樣會(huì)造成IO資源的耗盡，系統(tǒng)也再無擴(kuò)充的余地。因此，我們?cè)趯?shí)際應(yīng)用中只是將LED點(diǎn)陣的16條行線直接接在P0口和P2口，至于列選掃描信號(hào)則是由4-16線譯碼器74HC154來選擇控制，這樣便大大節(jié)約了IO口資源。同時(shí)考慮到P0口必需設(shè)置上拉電阻，我們采用10K排電阻作上拉電阻。實(shí)驗(yàn)中，漢字字符的顯示過程如下：在C2，C3，X1 以及單片機(jī)內(nèi)部時(shí)鐘電路的作用下，單片機(jī)AT89C51按照設(shè)定的程序在P0和P

5、2接口輸出與內(nèi)部漢字對(duì)應(yīng)的代碼電平送至 IED點(diǎn)陣的行選線(高電平驅(qū)動(dòng))，同時(shí)在P1.0、P1.1、P1.2、P1.3接口輸出列選掃描信號(hào)(低電平驅(qū)動(dòng))，從而選中相應(yīng)的象素LED發(fā)光，并利用人眼的視覺暫留特性合成整個(gè)漢字的顯示。(二)、漢字的點(diǎn)陣顯示原理及字庫代碼獲取方法實(shí)驗(yàn)中，每一個(gè)漢字由16行16列的點(diǎn)陣組成顯示。我們可以把每一個(gè)點(diǎn)理解為一個(gè)象素，而把每一個(gè)字的字形理解為一幅圖像。事實(shí)上這個(gè)漢字顯示屏不僅可以顯示漢字，也可以顯示在256象素范圍內(nèi)的任何圖形。如圖四所示。圖四、漢字的點(diǎn)陣顯示原理實(shí)驗(yàn)中通過列掃描方法獲取漢字的代碼，用AT89C51控制顯示。由于單片機(jī)的總線只有8位，一個(gè)字需要

6、拆分為2個(gè)部分。漢字被拆分為上部和下部，上部由8×16點(diǎn)陣組成，下部也由8×16點(diǎn)陣組成。如圖四，本實(shí)驗(yàn)通過列掃描方法首先顯示左上角的第一列的上半部分，即第0列的P0.7-P0.0口，顯示漢字“毛”時(shí)，為全滅，即二進(jìn)制00000000B，轉(zhuǎn)換為十六進(jìn)制為00H；第一列的下半部分，P2.7滅，P2.6滅，P2.5亮，P2.4滅，P2.3滅，P2.2滅，P2.1亮，P2.0滅，即二進(jìn)制00100000B，轉(zhuǎn)換為十六進(jìn)制為20H。如此，轉(zhuǎn)向第二列、第三列， 直至第十六列的掃描，一共掃描32個(gè)8位，這樣就可以得出漢字“毛”的掃描代碼為：00H,20H,44H,20H,44H,20H

7、,44H,20H44H,20H,44H,20H,7FH,0FCH,44H,22H44H,22H,44H,22H,44H,22H,44H,22H44H,22H,00H,22H,00H,2EH,00H,00H依靠人工方法獲取漢字代碼是非常繁瑣的事情，為此，我們采用點(diǎn)陣顯示字庫軟件來直接提取字符代碼。漢字點(diǎn)陣顯示一般有點(diǎn)掃描、行掃描、列掃描3種。本實(shí)驗(yàn)采用行掃描軟件提取漢字字符圖面如下。圖五、點(diǎn)陣顯示字庫軟件提取程序三、軟件設(shè)計(jì)（一）設(shè)計(jì)流程軟件程序主要由開始、初始化、主程序、字庫組成，程序設(shè)計(jì)流程圖如下所示。YN開始初始化查漢字上部數(shù)據(jù)及顯示查漢字下部數(shù)據(jù)及顯示是否顯示完延時(shí)并調(diào)整指針圖六、程序設(shè)

8、計(jì)流程圖（二）匯編語言實(shí)現(xiàn)如下：ORG 0000H;16*16點(diǎn)陣顯示AJMP MAINORG 0030H;以下程序從空間地址0030H開始存放，騰出中斷向量等所需空間MAIN:MOV DPTR,#TAB;字碼表初址賦值;以下字符單字循環(huán)MOV R1,#00H;列控制碼MOV R3,#16;列數(shù)MOV R4,#7;循環(huán)單片機(jī)仿真7個(gè)字符MMC1:MOV R5,#100;每屏反復(fù)顯示10次MOV R3,#16;列數(shù)MMC2:MOV R2,#0;取碼指針MMC3:MOV P0,#00H;初始時(shí)關(guān)顯示MOV P2,#00H;初始時(shí)關(guān)顯示MOV A,R2MOVC A,A+DPTR;取當(dāng)前列顯示字碼的第

9、一個(gè)字節(jié)MOV P0,A;送l-8行控制口INC R2MOV A,R2MOVC A,A+DPTR;取當(dāng)前列顯示字碼的第二個(gè)字節(jié)MOV P2,A;送9-15行控制口INC R2MOV P1,R1;送列控制碼INC R1ACALL D1MS;調(diào)用一毫秒延時(shí)程序DJNZ R3,MMC3;一屏16列是否顯示完MOV R3,#16DJNZ R5,MMC2;未顯示100次,繼續(xù)MOV P0,#00H;初始時(shí)關(guān)顯示MOV P2,#00H;初始時(shí)關(guān)顯示MOV R6,#32MMC4:INC DPTR;一屏反復(fù)顯示100次完,字碼表初值加32,顯示下一漢字DJNZ R6,MMC4DJNZ R4,MMC1;7個(gè)字符

10、未循環(huán)完,繼續(xù);以下字符從右向左移動(dòng)MOV R1,#00H;列控制碼MOV R3,#16;列數(shù)MOV R4,#208;移動(dòng)單片機(jī)仿真13個(gè)字符,13*16=208列MMC5:MOV R5,#10;每屏反復(fù)顯示10次MOV R3,#16;列數(shù)MMC6:MOV R2,#0;取碼指針MMC7:MOV P0,#00H;初始時(shí)關(guān)顯示MOV P2,#00H;初始時(shí)關(guān)顯示MOV A,R2MOVC A,A+DPTR;取當(dāng)前列顯示字碼的第一個(gè)字節(jié)MOV P0,A;送l-8行控制口INC R2MOV A,R2MOVC A,A+DPTR;取當(dāng)前列顯示字碼的第二個(gè)字節(jié)MOV P2,A;送9-15行控制口INC R2M

11、OV P1,R1;送列控制碼INC R1ACALL D1MS;調(diào)用一毫秒延時(shí)程序DJNZ R3,MMC7;一屏16列是否顯示完MOV R3,#16DJNZ R5,MMC6;未顯示10次,繼續(xù)INC DPTR;一屏反復(fù)顯示10次完,字碼表初值加2,使之從右向左移動(dòng)INC DPTRDJNZ R4,MMC5;208列未移動(dòng)完,繼續(xù);以下字符從左向右移動(dòng)MOV R1,#0FFH;列控制碼MOV R3,#16;列數(shù)MOV R4,#208;移動(dòng)單片機(jī)仿真13個(gè)字符,13*16=208列MMC8:MOV R5,#10;每屏反復(fù)顯示10次MOV R3,#16;列數(shù)MMC9:MOV R2,#0;取碼指針MMC1

12、0:MOV P0,#00H;初始時(shí)關(guān)顯示MOV P2,#00H;初始時(shí)關(guān)顯示MOV A,R2MOVC A,A+DPTR;取當(dāng)前列顯示字碼的第一個(gè)字節(jié)MOV P0,A;送l-8行控制口INC R2MOV A,R2MOVC A,A+DPTR;取當(dāng)前列顯示字碼的第二個(gè)字節(jié)MOV P2,A;送9-15行控制口INC R2MOV P1,R1;送列控制碼DEC R1ACALL D1MS;調(diào)用一毫秒延時(shí)程序DJNZ R3,MMC10;一屏16列是否顯示完MOV R3,#16DJNZ R5,MMC9;未顯示10次,繼續(xù)INC DPTR;一屏反復(fù)顯示10次完,字碼表初值加2,使之從右向左移動(dòng)INC DPTRDJ

13、NZ R4,MMC8;208列未移動(dòng)完,繼續(xù)AJMP MAIN;16列移動(dòng)完,返回,重新開始顯示D1MS: MOV R6,#50;50*10*2s=1msDELAY1:MOV R7,#10DELAY2:DJNZ R7,DELAY2 DJNZ R6,DELAY1RETRETTAB:;單字循環(huán)字符DB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00H,00H;DB 00H,00H,04H,0

14、4H,04H,08H,04H,10HDB 04H,20H,0FFH,0FEH,00H,00H,00H,00HDB 00H,00H,0FFH,0FCH,02H,02H,04H,02HDB 08H,02H,10H,02H,00H,1EH,00H,00H;北DB 00H,00H,20H,04H,20H,08H,27H,90HDB 24H,0A0H,24H,82H,0A4H,81H,64H,0FFHDB 24H,80H,24H,80H,24H,0A0H,27H,90HDB 20H,08H,20H,04H,00H,00H,00H,00H;京DB 00H,00H,10H,02H,11H,02H,12H,0

15、2HDB 16H,04H,99H,08H,50H,90H,30H,60HDB 10H,60H,10H,90H,19H,08H,16H,04HDB 12H,02H,11H,02H,10H,02H,00H,00H;交DB 02H,02H,82H,04H,63H,0F8H,00H,04HDB 00H,02H,4FH,0FAH,4AH,42H,4AH,42HDB 6AH,42H,5FH,0FAH,5AH,52H,6AH,4AHDB 4FH,0FAH,00H,02H,00H,02H,00H,00H;通DB 00H,00H,04H,02H,04H,04H,04H,08HDB 04H,10H,04H,20H

16、,04H,0C0H,0FFH,00HDB 04H,0C0H,04H,20H,04H,10H,04H,08HDB 04H,04H,04H,02H,04H,02H,00H,00H;大DB 02H,00H,0CH,40H,08H,40H,48H,40HDB 2AH,40H,1AH,40H,0AH,42H,4AH,41HDB 3AH,0FFH,0BH,40H,0AH,40H,18H,40HDB 2AH,40H,4CH,40H,08H,40H,00H,00H;學(xué);從右向左移動(dòng)字符DB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00

17、H,00HDB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00H,00H;DB 00H,00H,04H,04H,04H,08H,04H,10HDB 04H,20H,0FFH,0FEH,00H,00H,00H,00HDB 00H,00H,0FFH,0FCH,02H,02H,04H,02HDB 08H,02H,10H,02H,00H,1EH,00H,00H;北DB 00H,00H,20H,04H,20H,08H,27H,90HDB 24H,0A0H,24H,82H,0A4H,81H,64H,0FFHDB 24H,80H,24

18、H,80H,24H,0A0H,27H,90HDB 20H,08H,20H,04H,00H,00H,00H,00H;京DB 00H,00H,10H,02H,11H,02H,12H,02HDB 16H,04H,99H,08H,50H,90H,30H,60HDB 10H,60H,10H,90H,19H,08H,16H,04HDB 12H,02H,11H,02H,10H,02H,00H,00H;交DB 02H,02H,82H,04H,63H,0F8H,00H,04HDB 00H,02H,4FH,0FAH,4AH,42H,4AH,42HDB 6AH,42H,5FH,0FAH,5AH,52H,6AH,4A

19、HDB 4FH,0FAH,00H,02H,00H,02H,00H,00H;通DB 00H,00H,04H,02H,04H,04H,04H,08HDB 04H,10H,04H,20H,04H,0C0H,0FFH,00HDB 04H,0C0H,04H,20H,04H,10H,04H,08HDB 04H,04H,04H,02H,04H,02H,00H,00H;大DB 02H,00H,0CH,40H,08H,40H,48H,40HDB 2AH,40H,1AH,40H,0AH,42H,4AH,41HDB 3AH,0FFH,0BH,40H,0AH,40H,18H,40HDB 2AH,40H,4CH,40H

20、,08H,40H,00H,00H;學(xué)DB 02H,20H,02H,20H,02H,20H,22H,20HDB 12H,20H,0AH,3EH,06H,20H,02H,20HDB 02H,20H,02H,20H,02H,30H,42H,28HDB 42H,24H,42H,22H,7CH,20H,00H,00H;北DB 00H,40H,00H,80H,3FH,0FEH,00H,00HDB 00H,00H,0FH,0F8H,08H,08H,08H,08HDB 0FH,0F8H,00H,80H,04H,90H,08H,88HDB 10H,84H,20H,82H,00H,0A0H,00H,0C0H;京D

21、B 00H,20H,00H,40H,00H,80H,7FH,0FEHDB 04H,20H,08H,10H,18H,18H,24H,24HDB 02H,40H,01H,80H,01H,80H,02H,40HDB 04H,20H,08H,10H,70H,0EH,00H,00H;交DB 00H,02H,1FH,0E4H,09H,04H,06H,00HDB 1FH,0E0H,12H,20H,1FH,0E7H,12H,24HDB 12H,24H,1FH,0E4H,12H,24H,16H,24HDB 1AH,24H,00H,0AH,7FH,0F1H,00H,00H;通DB 00H,80H,00H,80H,

22、00H,80H,00H,80HDB 00H,80H,7FH,0FEH,00H,80H,00H,80HDB 01H,40H,01H,40H,02H,20H,04H,10HDB 08H,08H,10H,04H,60H,02H,00H,00H;大DB 00H,00H,20H,88H,11H,10H,09H,20HDB 7FH,0FEH,20H,02H,17H,0F1H,02H,00HDB 01H,00H,01H,00H,7FH,0FEH,01H,00HDB 01H,00H,01H,00H,01H,40H,01H,80H;學(xué);從左向右移動(dòng)字符DB 00H,00H,00H,00H,00H,00H,00H

23、,00HDB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00H,00HDB 00H,00H,00H,00H,00H,00H,00H,00H;DB 00H,00H,00H,1EH,10H,02H,08H,02HDB 04H,02H,02H,02H,0FFH,0FCH,00H,00HDB 00H,00H,00H,00H,0FFH,0FEH,04H,20HDB 04H,10H,04H,08H,04H,04H,00H,00H;北DB 00H,00H,00H,00H,20H,04H,20H,08HDB 27H,90H,24H,0A

24、0H,24H,80H,24H,80HDB 64H,0FFH,0A4H,81H,24H,82H,24H,0A0HDB 27H,90H,20H,08H,20H,04H,00H,00H;京DB 00H,00H,10H,02H,11H,02H,12H,02HDB 16H,04H,19H,08H,10H,90H,10H,60HDB 30H,60H,50H,90H,99H,08H,16H,04HDB 12H,02H,11H,02H,10H,02H,00H,00H;交DB 00H,00H,00H,02H,00H,02H,4FH,0FAHDB 6AH,4AH,5AH,52H,5FH,0FAH,6AH,42HD

25、B 4AH,42H,4AH,42H,4FH,0FAH,00H,02HDB 00H,04H,63H,0F8H,82H,04H,02H,02H;通DB 00H,00H,04H,02H,04H,02H,04H,04HDB 04H,08H,04H,10H,04H,20H,04H,0C0HDB 0FFH,00H,04H,0C0H,04H,20H,04H,10HDB 04H,08H,04H,04H,04H,02H,00H,00H;大DB 00H,00H,08H,40H,4CH,40H,2AH,40HDB 18H,40H,0AH,40H,0BH,40H,3AH,0FFHDB 4AH,41H,0AH,42H,

26、1AH,40H,2AH,40HDB 48H,40H,08H,40H,0CH,40H,02H,00H;學(xué)DB 04H,40H,04H,40H,04H,40H,04H,44HDB 04H,48H,7CH,50H,04H,60H,04H,40HDB 04H,40H,04H,40H,0CH,40H,14H,42HDB 24H,42H,44H,42H,04H,3EH,00H,00H;北DB 02H,00H,01H,00H,7FH,0FCH,00H,00HDB 00H,00H,1FH,0F0H,10H,10H,10H,10HDB 1FH,0F0H,01H,00H,09H,20H,11H,10HDB 21H

27、,08H,41H,04H,05H,00H,03H,00H;京DB 04H,00H,02H,00H,01H,00H,7FH,0FEHDB 04H,20H,08H,10H,18H,18H,24H,24HDB 02H,40H,01H,80H,01H,80H,02H,40HDB 04H,20H,08H,10H,70H,0EH,00H,00H;交DB 40H,00H,27H,0F8H,20H,90H,00H,60HDB 07H,0F8H,04H,48H,0E7H,0F8H,24H,48HDB 24H,48H,27H,0F8H,24H,48H,24H,68HDB 24H,58H,50H,00H,8FH,0

28、FEH,00H,00H;通DB 01H,00H,01H,00H,01H,00H,01H,00HDB 01H,00H,7FH,0FEH,01H,00H,01H,00HDB 02H,80H,02H,80H,04H,40H,08H,20HDB 10H,10H,20H,08H,40H,06H,00H,00H;大DB 00H,00H,11H,04H,08H,88H,04H,90HDB 7FH,0FEH,40H,04H,8FH,0E8H,00H,40HDB 00H,80H,7FH,0FEH,00H,80H,00H,80HDB 00H,80H,00H,80H,02H,80H,01H,80H;學(xué)END在Kei

29、l軟件中完成程序編寫、調(diào)試和編譯之后，生成最終的可支持單片機(jī)工作的HEX文件，如圖六所示。經(jīng)過不斷調(diào)試和修改，以上程序可以實(shí)現(xiàn)預(yù)定的功能和要求。圖七、Keil軟件程序編寫、調(diào)試和編譯四、Proteus軟件仿真Proteus軟件不僅能仿真單片機(jī)外圍電路或沒有單片機(jī)參與的其它電路的工作情況，也能仿真單片機(jī)CPU的工作情況。因此在仿真和程序調(diào)試時(shí)，是從工程的角度直接看程序運(yùn)行和電路工作的過程和結(jié)果。從某種意義上看，Proteus仿真基本接近于工程應(yīng)用。事實(shí)上，為完成本實(shí)驗(yàn)，實(shí)驗(yàn)過程中，我首先是通過Proteus軟件仿真設(shè)計(jì)了電路圖，并進(jìn)行了大量的修改和調(diào)試，才確定了實(shí)驗(yàn)的最終的電路圖和設(shè)計(jì)程序。由此

30、，才開始購(gòu)買元器件并焊接電路板，最終成功在電路板上顯示點(diǎn)陣式漢字，實(shí)現(xiàn)了本實(shí)驗(yàn)的目的和要求。Proteus軟件仿真圖如下所示。圖八、Proteus軟件電路仿真 需要說明的是，Proteus軟件仿真中，單片機(jī)無需連接時(shí)鐘電路和復(fù)位電路，軟件默認(rèn)單片機(jī)已具備正常工作的條件。同時(shí)，Proteus軟件中，并未提供16×16點(diǎn)陣，實(shí)際電路設(shè)計(jì)中采用了4個(gè)8×8點(diǎn)陣合并而成。圖中點(diǎn)陣中間顯示中多余的紅色和藍(lán)色豎線是8×8點(diǎn)陣的管腳高低電平顯示所致，并不影響實(shí)際的電路仿真結(jié)果。其中，紅色代表管腳處為高電平，藍(lán)色代表管腳處為低電平。五、電路板元器件選擇實(shí)驗(yàn)所用電路板焊接元器件清單

31、如下：元件編號(hào)規(guī)格參數(shù)使用個(gè)數(shù)作用說明U1AT89C511核心控制芯片LED116×16LED點(diǎn)陣1組成漢字顯示屏IC274HC15414線-16線譯碼器IC3,IC410K排阻2上拉電阻R21K1復(fù)位電路C122F/16V1K1按鍵開關(guān)1X112MHz晶振1時(shí)鐘電路C2,C320pF2電路板15cm*10cm電路板1元件承載體六、實(shí)驗(yàn)體會(huì)本次實(shí)驗(yàn)前后共耗時(shí)兩周有余。前期首先確定實(shí)驗(yàn)課題，并對(duì)課題進(jìn)行探討研究和資料搜索。中期，則在確定點(diǎn)陣式顯示器設(shè)計(jì)的課題基礎(chǔ)上，了解點(diǎn)陣式顯示器的顯示原理，設(shè)計(jì)實(shí)驗(yàn)電路原理圖，并編寫程序在Keil軟件中編譯和調(diào)試，隨后根據(jù)已編寫的匯編程序，在Prot

32、ues軟件中仿真實(shí)現(xiàn)模擬顯示結(jié)果。在仿真過程中，隨時(shí)根據(jù)仿真的顯示結(jié)果，修改和調(diào)整原匯編程序。后期，根據(jù)完整的實(shí)驗(yàn)匯編程序和合理的實(shí)驗(yàn)電路原理圖，焊接電路板，并不斷檢查焊接錯(cuò)誤，最終物理實(shí)現(xiàn)16×16點(diǎn)陣式LED顯示器的全部設(shè)計(jì)。實(shí)驗(yàn)中遇到了很多問題和疑惑，通過翻閱書籍、查看網(wǎng)上資料，這些都得到了很好的解決。前期，在實(shí)驗(yàn)室實(shí)驗(yàn)電路箱簡(jiǎn)單測(cè)試了8×8點(diǎn)陣式顯示。由于實(shí)驗(yàn)電路箱IO口資源有限，僅有P1八個(gè)口和P3.2、P3.3、P3.4、P3.5四個(gè)口共十二個(gè)端口可用，故需擴(kuò)展。實(shí)驗(yàn)電路箱提供了8155 并行接口芯片、74LS377、74LS244等芯片，可用來擴(kuò)展所需IO端口

33、。在仿真模式下，跳線選擇器JP2中的P3.0、P3.1必須置A位。中期，16×16點(diǎn)陣式LED顯示器的引腳排列是相當(dāng)重要的，它的三十二個(gè)引腳分別接至P0口、P2口和列驅(qū)動(dòng)電路芯片74HC154的輸出端口。為此，我查閱了相關(guān)的網(wǎng)上資料，并實(shí)際用萬用表一一測(cè)試了點(diǎn)陣的三十二個(gè)引腳，最終得出了16×16點(diǎn)陣式LED顯示器的引腳排列，如圖三所示。其中1-8、9-16代表點(diǎn)陣的列，2 4 3 1、7 5 6 8、9 11 12 10、16 14 13 15代表點(diǎn)陣的行。當(dāng)點(diǎn)陣的列引腳為低電平，行引腳為高電平時(shí)，所對(duì)應(yīng)的列和行確定的二極管被點(diǎn)亮。在實(shí)驗(yàn)電路箱上用Keil軟件硬件調(diào)試時(shí)，需設(shè)置調(diào)試環(huán)境