到昨天为止，用了一个星期写了一个汇编程序，是这个学期课程设计的作业。这大概是我接触到的最长的一个汇编了吧，感觉真BT。
目的很简单，就是有八个按钮，分别控制千、百、十、个位的+-（比如按百位的+数字就加100），带进位，在4个7晶体管上显示相应的4位数字，初始值为0000。
ORG 8000H
LJMP MAIN
ORG 8003H
LJMP PKEYI
ORG 8100H
MAIN: MOV R1,#7BH
MOV R6,#4H
START: MOV @R1,#0
DEC R1
DJNZ R6,START
LCALL INI79
LCALL RDIR
PROGN: JNB 00H,PROGN
CLR 00H
MOV R0,#40H
MOV A,@R0
CJNEA,#00,NEXT1
LCALL PROGN0
NEXT1: CJNE A,#02,NEXT2
LCALL PROGN1
NEXT2: CJNE A,#03,NEXT3
LCALL PROGN2
NEXT3: CJNE A,#04,NEXT4
LCALL PROGN3
NEXT4: CJNE A,#05,NEXT5
LCALL PROGN4
NEXT5: CJNE A,#06,NEXT6
LCALL PROGN5
NEXT6: CJNE A,#07,NEXT7
LCALL PROGN6
NEXT7: CJNE A,#08,PROGN
LCALL PROGN7
LCALL 8900H
LJMP PROGN
ORG 8400H
PROGN0: MOV R1,#7BH
MOV A,@R1
CJNE A,#9H,ADD0
MOV @R1,#00H
LJMP EXIT0
ADD0: INC @R1
EXIT0: LCALL 8900H
RET
ORG 8450H
PROGN1: MOV R1,#7BH
MOV A,@R1
CJNE A,#0H,SUB0
LJMP EXIT1
SUB0: DEC @R1
EXIT1: LCALL 8900H
RET
ORG 8500H
PROGN2: MOV R1,#7AH
MOV A,@R1
CJNE A,#9H,ADD1
MOV @R1,#0H
LCALL PROGN0
LJMP EXIT2
ADD1: INC @R1
EXIT2: LCALL 8900H
RET
ORG 8550H
PROGN3: MOV R1,#7AH
MOV A,@R1
CJNE A,#0H,SUB1
MOV @R1,#9H
LCALL PROGN1
LJMP EXIT3
SUB1: DEC @R1
EXIT3: LCALL 8900H
RET
ORG 8600H
PROGN4: MOV R1,#79H
MOV A,@R1
CJNE A,#9H,ADD2
MOV @R1,#0H
LCALL PROGN2
LJMP EXIT4
ADD2: INC @R1
EXIT4: LCALL 8900H
RET
ORG 8650H
PROGN5: MOV R1,#79H
MOV A,@R1
CJNE A,#9H,SUB2
MOV @R1,#9H
LCALL PROGN3
LJMP EXIT5
SUB2: DEC @R1
EXIT5: LCALL 8900H
RET
ORG 8700H
PROGN6: MOV R1,#78H
MOV A,@R1
CJNE A,#9H,ADD3
MOV @R1,#0H
LCALL PROGN4
LJMP EXIT6
ADD3: INC @R1
EXIT6: LCALL 8900H
RET
ORG 8750H
PROGN7: MOV R1,#78H
MOV A,@R1
CJNE A,#0H,SUB3
MOV @R1,#9H
LCALL PROGN5
LJMP EXIT7
SUB3: DEC @R1
EXIT7: LCALL 8900H
RET
ORG 8800H
INI79: MOV DPTR,#0DFFFH
MOV A,#0DCH
MOVX @DPTR,A
WNDU: MOVX A,@DPTR
JB ACC.7,WNDU
MOV A,#0
MOVX @DPTR,A
MOV A,#34
MOVX @DPTR,A
MOV IE,#81H
RET
ORG 8900H
RDIR: MOV DPTR,#0DFFFH
MOV A, #90H
MOVX @DPTR,A
MOV R0,#7BH
MOV R7,#4
MOV DPTR,#0DEFFH
RDL0: MOV A,@R0
ADD A,#6
MOVC A,@A+PC
CPL A
MOVX @DPTR,A
DEC R0
DJNZ R7,RDL0
RET
SEG: DB 3FH,6,5BH,4FH,
DB 66H,6DH,
DB 7DH,7,7FH,6FH,
DB 77H,7CH
DB 39H,5EH,79H,71H,
DB 73H,3EH,
DB 31H,6FH,1CH,23H,40H,3,
DB 18H,38H,0
ORG 8A00H
PKEYI: PUSH PSW
PUSH DPL
PUSH DPH
PUSH ACC
PUSH B
SETB PSW.3
MOV DPTR,#0DFFFH
MOVX A,@DPTR
ANL A,#0FH
JZ PKYR
MOV A,#40H
MOVX @DPTR,A
MOV DPTR,#0DEFFH
MOVX A,@DPTR
MOV R2,A
ANL A,#18H
RR A
RR A
RR A
MOV B,#2
MUL AB
XCH A,R2
ANL A,#3
ADD A,R2
MOV R0,#40H
MOV @R0,A
SETB 0
PKYR: POP B
POP ACC
POP DPH
POP DHL
POP PSW
RET1