输入按键并显示：4×4矩阵键盘分别定义为：0、1、2、3、4、5、。。。、E、F，16个按键。当键入一个按键，在一位数码管上显示键值。（汇编语言）
TEMP DATA 32H
ORG 0000H
AJMP START
START:
MOV SP,60H
MOV P0,#00H
MAIN:
LCALL KEYBOARD
LJMP MAIN
KEYBOARD:
ROW1:
MOV P1,#0EFH
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,0F0H,L100
LJMP ROW2
L100:
LCALL DELAY10MS
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,#0F0H,COLUMN1_1
LJMP ROW2
COLUMN1_1:
MOV TEMP,P1
MOV A,TEMP
CJNE A,#0E7H,COLUMN1_2
MUM0:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#68
LOOP1:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN1_2:
CJNE A,#0EBH,COLUMN1_3
MUM1:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#69
LOOP2:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN1_3:
CJNE A,#0EDH,COLUMN1_4
MUM2:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#70
LOOP3:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN1_4:
CJNE A,#0EEH,ROW2
MUM3:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#71
LOOP4:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
ROW2:
MOV P1,#0DFH
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,0F0H,L200
LJMP ROW3
L200:
LCALL DELAY10MS
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,#0F0H,COLUMN2_1
LJMP ROW3
COLUMN2_1:
MOV TEMP,P1
MOV A,TEMP
CJNE A,#0D7H,COLUMN2_2
MUM4:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#72
LOOP5:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN2_2:
CJNE A,#0DBH,COLUMN2_3
MUM5:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#73
LOOP6:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN2_3:
CJNE A,#0DDH,COLUMN2_4
MUM6:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#74
LOOP7:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN2_4:
CJNE A,#0DEH,ROW3
MUM7:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#75
LOOP8:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
ROW3:
MOV P1,#0BFH
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,0F0H,L300
LJMP ROW4
L300:
LCALL DELAY10MS
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,#0F0H,COLUMN3_1
LJMP ROW4
COLUMN3_1:
MOV TEMP,P1
MOV A,TEMP
CJNE A,#0B7H,COLUMN3_2
MUM8:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#76
LOOP9:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN3_2:
CJNE A,#0BBH,COLUMN3_3
MUM9:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#77
LOOP10:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN3_3:
CJNE A,#0BDH,COLUMN3_4
CH_A:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#78
LOOP11:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN3_4:
CJNE A,#0BEH,ROW4
CH_B:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#79
LOOP12:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
ROW4:
MOV P1,#07FH
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,0F0H,L400
LJMP KEYBOARD
L400:
LCALL DELAY10MS
MOV TEMP,P1
ANL TEMP,#0F0H
MOV A,TEMP
CJNE A,#0F0H,COLUMN4_1
LJMP KEYBOARD
COLUMN4_1:
MOV TEMP,P1
MOV A,TEMP
CJNE A,#077H,COLUMN4_2
CH_C:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#80
LOOP13:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN4_2:
CJNE A,#07BH,COLUMN4_3
CH_D:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#81
LOOP14:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN4_3:
CJNE A,#07DH,COLUMN4_4
CH_E:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#82
LOOP15:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLUMN4_4:
CJNE A,#07EH,COLSCANEND
CH_F:
MOV DPTR,#NUM_TABLE
MOV R0,#68
MOV A,#83
LOOP16:
SUBB A,R0
MOVC A,@A+DPTR
MOV P0,A
RET
COLSCANEND:
RET
DELAY10MS:
PUSH 30H
PUSH 30H
MOV 30H,#173
MOV 31H,#27
NEXT:
DJNZ 31H,NEXT
DJNZ 30H,NEXT
POP 31H
POP 30H
RET
NUM_TABLE:
DB 3FH,06H,5BH,4FH,66H
DB 6DH,7DH,07H,7FH,6FH,77H
DB 7CH,39H,5EH,79H
DB 71H
END按键显示0-F硬件调试结果：
