【文章內容簡介】 JNZ TIME2 LOOP TIME1 POP CX POP AX RET；STTK: CALL DISP ；放鍵測試程序 MOV AL,00H OUT 60H,AL IN AL,62H AND AL,60H CMP AL,60H JNZ STTK JMP STTCODE ENDS END START ：實現(xiàn)：a)定義鍵盤按鍵，5個為數(shù)字鍵7，7個功能鍵：減號—，除號247。，等號＝；b)可進行三位8進制減法運算；c)可進行兩位10進制除法運算。：STACK SEGMENT STACK DW 64 DUP (?)STACK ENDSDATA SEGMENTVAR1 DB 07H,0BH,0DH,0EH ；數(shù)碼管位碼VAR2 DB 3FH,3FH,3FH,3FH,3FHVAR3 DB 00H,00H,00H,00H,00H ；當前值VAR4 DB 00H,00H,00H,00H,00H ；保存值TABL DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H DB 7FH,6FH,77H,7CH,39H,5EH,79H,71HDATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART: MOV AX,DATA MOV DS,AX MOV AL,88H OUT 63H,AL ；8255A初始化 MOV BX,0000H ；BX清零STT: MOV AL,00H ；鍵盤測試 OUT 60H,ALNEXT: IN AL,62H AND AL,60H CMP AL,60H JNZ KEYABC CALL DISP ；調用顯示程序 JMP STT；KEYABC: CALL TIME ；延時,去抖動 IN AL,62H AND AL,60H CMP AL,60H JNZ KEY JMP STTKEY: MOV AL,0FEH ；鍵盤掃描識別 OUT 60H,AL IN AL,62H TEST AL,40H JNZ KEY_4 CALL KEYDEN JMP STTKKEY_4: TEST AL,20H JNZ KEY_JIAN CALL KEY4 JMP STTKKEY_JIAN:MOV AL,0FDH OUT 60H,AL IN AL,62H TEST AL,40H JNZ KEY_5 CALL KEYJIAN JMP STTKKEY_5: TEST AL,20H JNZ KEY_CHU CALL KEY5 JMP STTKKEY_CHU: MOV AL,0FBH OUT 60H,AL IN AL,62H TEST AL,40H JNZ KEY_6 CALL KEYCHU JMP STTKKEY_6: TEST AL,20H JNZ KEY_3 CALL KEY6 JMP STTKKEY_3: MOV AL,0F7H OUT 60H,AL IN AL,62H TEST AL,40H JNZ KEY_7 CALL KEY3 JMP STTKKEY_7: TEST AL,20H JNZ KEY_71 CALL KEY7KEY_71: JMP STTK；KEY3: CMP BH,00H ；按鍵3處理子程序 JZ KEY3_1 ；未按過符號鍵,不清零 CALL CLEAR ；已按過符號鍵,清零KEY3_1: CALL LP1 ；低4位字節(jié)前移 MOV AL,03H MOV [DI+4],AL PUSH BX ；保護BX LEA BX,TABL XLAT TABL MOV [SI+4],AL CALL DISP ；顯示 POP BX RET ；返回；KEY4: CMP BH,00H ；按鍵4處理子程序 JZ KEY4_1 CALL CLEARKEY4_1: CALL LP1 MOV AL,04H MOV [DI+4],AL PUSH BX LEA BX,TABL XLAT TABL MOV [SI+4],AL CALL DISP POP BX RET；KEY5: CMP BH,00H ；按鍵5處理子程序 JZ KEY5_1 CALL CLEARKEY5