微機課程設計講述

1、PC機實時時鐘的設計利用PC機現(xiàn)有的硬件和軟件資源設計程序,以實現(xiàn)在顯示器上顯示XX(時)：XX(分)：XX(秒)。DATA SEGMENTCOUNT DB 100;*初始的時間顯示*TENH DB '1'HOUR DB '2:'TENM DB '0'MINUTE DB '0' DB ':'TENS DB '0'SECOND DB '0',0DH,0DH,'$'初始顯示12:00:00;*初始的界面顯示內(nèi)容*ENTER1 DB " -WELCOME-&quo

2、t;,0AH,0DH DB " BaoYan 120900931 ",0AH,0DH DB " All Rights Reserved ",0AH,0DHENTER2 DB ' The Time Now is ',10 DUP(0)ENTER3 DB 'Do you want to change the time? Y/N'ENTER4 DB '*-When finished changing the time,please press "enter" to continue-*'ENT

3、ER5 DB '*-You can press the left or right button for changing the hour ,minute -*'ENTER6 DB '*-or second that you want-*'DATA ENDSSTACK SEGMENT PARA STACK 'STACK'DB 256 DUP(0)STACK ENDSCODE SEGMENTASSUME CS:CODE,DS:DATA,SS:STACKSTART PROC FARPUSH DSMOV AX,0PUSH AX;標準序返回DOSMOV

4、 AH,07HINT 21H;初始時無顯示，此時等待鍵盤輸入，AL=字符的ASCII碼，輸入無回顯;*將中斷矢量壓入堆棧保存*CLI;關中斷，防止有些硬件對中斷的干擾CLD;使DF=0MOV AX,0000HMOV DS,AXMOV SI,0020H;DS:SI指向08H中斷向量LODSW;取08中斷入口的偏移地址MOV BX,AXLODSW;取08中斷入口的段地址PUSH AXPUSH BX;壓棧保護MOV AX,DATAMOV DS,AX;建立數(shù)據(jù)段的可尋址性;*將中斷向量壓入新地址*MOV AX,0000HMOV ES,AXMOV DI,0020H;ES:DS指向08中斷向量存放地址MO

5、V AX,OFFSET TIMERSTOSW;寫入偏移地址MOV AX,CSSTOSW;寫入段地址MOV AL,00110110B;8253初始化，0通道，方式3，二進制計數(shù)OUT 43H,ALMOV AX,11932;計數(shù)初值=11932OUT 40H,ALMOV AL,AHOUT 40H,ALIN AL,21H;讀8259的中斷屏蔽寄存器IMRPUSH AX;壓棧保護，AL的值為0FCHSTI;開中斷MOV AH,1MOV CH,30HINT 10H;置光標類型CALL CLEAN_SCREEN;清屏;*屏幕初始化*PUSH AXPUSH BXMOV AX,0600H ;AH=06(滾動)

6、AL=00(全屏空白)MOV BH,000CH;設置背景顏色(3)和前景顏色(e)SUB CX,CX;從0行0列開始MOV DX,8F8FH;到8F行8F列INT 10HPOP AXPOP BX;*顯示ENTER1的內(nèi)容*MOV DH,1;行號MOV DL,0;列號MOV BH,0;頁號MOV AH,2;置光標位置INT 10HMOV CX,199MOV SI,OFFSET ENTER1SHOW:MOV AH,0EH;顯示字符（光標前移 ） ，al 字符， bl 前景色MOV AL,SIINT 10HINC SILOOP SHOW;*顯示ENTER2的內(nèi)容*PUSHESPUSHBPPUSHBX

7、PUSHCXPUSHDX;保護現(xiàn)場，讓寄存器壓棧（后同）MOV BP,OFFSET ENTER2;取ENTER2的偏移地址（后同）MOVAX,SEG ENTER2;取ENTER2的段地址（后同）MOVES,AX;ES:BP為欲顯示的字符串地址（后同）MOVCX,60;假設字符串長度為60（后同）MOVBX,0007H;BH=00，為頁號,BL=07H為顯示的字符串屬性，為銀白色（后同）MOVDX,0600H;起始行為06，起始列為00（后同）MOVAL,1MOVAH,13HINT 10HPOP DXPOP CXPOP BXPOP BPPOP ES;*顯示ENTER3的內(nèi)容*PUSHESPUSH

8、BPPUSHBXPUSHCXPUSHDXMOV BP,OFFSET ENTER3MOVAX,SEG ENTER3MOVES,AXMOVCX,40MOVBX,0007HMOVDX,0C00HMOVAL,1MOVAH,13HINT 10HPOP DXPOP CXPOP BXPOP BPPOP ES;*顯示ENTER4的內(nèi)容*PUSHESPUSHBPPUSHBXPUSHCXPUSHDXMOV BP,OFFSET ENTER4MOVAX,SEG ENTER4MOVES,AXMOVCX,48HMOVBX,0007HMOVDX,0D00HMOVAL,1MOVAH,13HINT 10HPOP DXPOP C

9、XPOP BXPOP BPPOP ES;*顯示ENTER5的內(nèi)容*PUSHESPUSHBPPUSHBXPUSHCXPUSHDXMOV BP,OFFSET ENTER5MOVAX,SEG ENTER5MOVES,AXMOVCX,4DHMOVBX,0007HMOVDX,0E00HMOVAL,1MOVAH,13HINT 10HPOP DXPOP CXPOP BXPOP BPPOP ES;*顯示ENTER6的內(nèi)容*PUSHESPUSHBPPUSHBXPUSHCXPUSHDXMOV BP,OFFSET ENTER6MOVAX,SEG ENTER6MOVES,AXMOVCX,1FHMOVBX,0007HM

10、OVDX,0F00HMOVAL,1MOVAH,13HINT 10HPOP DXPOP CXPOP BXPOP BPPOP ESFOREVER:MOV DL,0FFHMOV AH,06HINT 21H;判斷鍵盤是否有輸入MOV DL,ALMOV AH,02HINT 21H;顯示鍵盤輸入的字符JZ DISP;無鍵按下則轉(zhuǎn)顯示DISPCMP AL,20H;判斷按鍵是否為空格JZ EXIT1;若為空格，則退出程序CMP AL,'Y'JZ CHANGECMP AL,'y'JZ CHANGE;判斷是否為“Y”或者“y”，若是則轉(zhuǎn)到修改函數(shù);*顯示時間模塊*DISP:PUSH

11、ESPUSHBPPUSHBXPUSHCXPUSHDXMOV BP,OFFSET TENHMOVAX,SEG TENHMOVES,AXMOVCX,8;顯示從TENH開始的八個字符串，即時間MOVBX,000CHMOVDX,0923HMOVAL,1MOVAH,13HINT 10HPOP DXPOP CXPOP BXPOP BPPOP ESMOV BH,0MOV DX,0C2AHMOV AH,02HINT 10H;將光標置于0CH行的2AH列MOV AL,SECOND;取秒單元值WAITCHA: CMP AL,SECOND;判斷秒的數(shù)值是否改變JZ WAITCHA;沒有改變則繼續(xù)等待JMP FORE

12、VER;改變則轉(zhuǎn)FOREVEREXIT1:JMP EXIT;*修改時間模塊*CHANGE:MOVDX,0923H;將光標位置鎖定到時鐘的第一位CHANGE1:MOVAH,02HINT10H;鎖定光標位置，DH為行，DL為列MOVAL,0MOVCX,DXSUBCX,0923H;判定當前光標在時鐘的第幾位，存在CX里LEASI,TENHADDSI,CX;將SI指向當前光標位置所顯示存儲單元，以便進行修改MOVAH,0INT16H;讀取鍵盤按鍵信息，存在AL里，但并不回顯CMPAL,0DH;0DH為回車的ASCII碼，當鍵盤敲入回車時，則繼續(xù)顯示時間JZFOREVERCMPAH,4DH;判斷是否按了

13、右方向鍵JZWRI2;若按了右方向鍵則轉(zhuǎn)WRI2CMPAH,4BH;判斷是否按了左方向鍵JZMOVE2;若按了左方向鍵則轉(zhuǎn)MOVE2CMPAL,30HJBCHANGE1;輸入小于0作無效處理;*對輸入的時間值進行判斷模塊*HOUR_H:CMP CX,0;對小時高位輸入判斷JNZ HOUR_L;判斷是否是小時的高位，若不是則指向小時的低位CMP AL,'2'將輸入小時的高位的值判斷JA CHANGE1;若大于2，無效，轉(zhuǎn)到CHANGE1JMP WRI1;否則將其寫入（后同）HOUR_L: CMP CX,1;對小時低位輸入判斷JNZ MINU_H;判斷是否是小時的低位，若不是則指向

14、分鐘的高位MOV BL,TENHCMP BL,'2'判斷高位是否為2JZ HOUR_2;高位是2則轉(zhuǎn)向HOUR_2CMP AL,'9'JA CHANGE1;高位不為2時，低位可以輸入小于等于9的數(shù)JMP WRI1HOUR_2: CMP AL,'3'高位為2時，低位只能輸入小于等于3的數(shù)JA CHANGE1JMP WRI1MINU_H: CMP CX,3;對分鐘高位輸入判斷JNZ MINU_L;判斷是否是分鐘的高位，若不是則指向分鐘的低位CMP AL,'5'將輸入的數(shù)與5比較JA CHANGE1;若大于5無效JMP WRI1MINU

15、_L:CMP CX,4;對分鐘低位輸入判斷JNZ SEC_H;判斷是否是分鐘的低位，若不是則指向秒鐘的高位CMP AL,'9'將輸入分鐘的低位與9比較JA CHANGE1;大于9無效JMP WRI1SEC_H: CMP CX,6;對秒鐘高位輸入判斷JNZ SEC_L;判斷是否是秒鐘的高位，若不是則指向秒鐘的低位CMP AL,'5'將輸入的數(shù)與5比較JA CHANGE1;若大于5無效JMP WRI1SEC_L:CMP CX,7;對秒鐘低位低位判斷JNZ CHANGE1;光標不在時鐘上時，輸入不回顯也不處理CMP AL,'9'將輸入分鐘的低位與9比較

16、JA CHANGE1;大于9無效WRI1:MOVSI,AL;將輸入的字符存到對應內(nèi)存單元MOVAH,0EH;同時將輸入的字符顯示在當前位置INT10HJMP WRI2WRI2:MOVAL,SI+1;按下右方向鍵，則使偏移量加1CMPAL,':'當下一位為“：”時，則對DX加兩次，否則跳過它JNZMOVE1INCDXMOVE1:INCDX;每修改一位，把光標向后移一位JMP CHANGE1MOVE2:MOVAL,SI-1;當輸入左方向鍵時，使偏移量減1CMPAL,':'當下一位為“：”時，則對DX減兩次，否則跳過它JNZMOVE3DECDXMOVE3:DECDX;

17、每修改一位，把光標向前移一位JMPCHANGE1EXIT:CLI;有空格鍵按下時退出，關中斷CLD;清方向標志位POP AXOUT 21H,AL;恢復IMRMOV AL,36H;8253初始化，55msOUT 43H,ALMOV AL,0OUT 40H,ALOUT 40H,AL;*恢復中斷向量*MOV AX,0MOV ES,AXMOV DI,4*8POP AXSTOSWPOP AXSTOSWSTIRETSTART ENDP;*時間進位模塊*TIMER PROC FARPUSH AXDEC COUNTJNZ L2;不到一秒轉(zhuǎn)L2MOV COUNT,100;到1秒，重置COUNT,并修改時間INC

18、 SECONDCMP SECOND,'9'JLE TIMEXT;如果小于等于9，轉(zhuǎn)至TIMEXT(后同)MOV SECOND,'0'INC TENSCMP TENS,'6'JL TIMEXTMOV TENS,'0'INC MINUTECMP MINUTE,'9'JLE TIMEXTMOV MINUTE,'0'INC TENMCMP TENM,'6'JL TIMEXTMOV TENM,'0'JMP L3L2:JMP TIMEXTL3:MOV AL,HOURAND AL,0FHMOV AH,TENHAND AH,0FHMOV CL,4ROR AH,CLOR AL,AH;AH放到AL高四位ADD AL,1DAACMP AL,24JL L1;小于24轉(zhuǎn)L1，否則置0MOV TENH,'0'MOV HOUR,'0'JMP TIMEXTL1:MOV AH,ALAND AL,0FHOR AL,30HMOV HOUR,ALMOV CL,4ROR AH,CLAND AH,0FHOR AH,30HMOV TENH,AHTIMEXT :;中斷結(jié)束MOV AL,