key.asm

51单片机基础篇 对于有一定基础的人看看 包含书中所以的源代码

  
	ORG     0H
BEGIN:  
KEYBOARD:
	CALL    GET_KEY
	CALL    DISPLAY
	SJMP    KEYBOARD
DISPLAY:
	CALL    SEGCODE 
	MOV     P3,A
	RET
SEGCODE:  
	INC     A
	MOVC    A,@A+PC
	RET
;7_SEG_TABLE            
	DB      00111111B,00000110B,01011011B
	DB      01001111B,01100110B,01101101B
	DB      01111101B,00100111B,01111111B
	DB      01101111B,01110111B,01111100B         
	DB      00111001B,01011110B,01111001B
	DB      01110001B 
GET_KEY:
AGAIN:  
	MOV     R1,#4
	MOV     A,#00010000B
GET:        
	MOV     P1,A     
	MOV     A,P1
	PUSH    ACC
	ANL     A,#00001111B
	CJNE    A,#0,KEY_IN
	POP     ACC
	RL      A
	DJNZ    R1,GET
	SJMP    AGAIN
KEY_IN:
	POP     ACC
KEY_0:   
	CJNE    A,#10001000B,KEY_1  
	MOV     A,#0
	RET
KEY_1:
	CJNE    A,#10000100B,KEY_2       
	MOV     A,#1
	RET
KEY_2:
	CJNE    A,#10000010B,KEY_3
	MOV     A,#2
	RET
KEY_3:
	CJNE    A,#10000001B,KEY_4
	MOV     A,#3
	RET
KEY_4:          
	CJNE    A,#01001000B,KEY_5
	MOV     A,#4
	RET
KEY_5:
	CJNE    A,#01000100B,KEY_6       
	MOV     A,#5
	RET
KEY_6:
	CJNE    A,#01000010B,KEY_7
	MOV     A,#6
	RET
KEY_7:
	CJNE    A,#01000001B,KEY_8
	MOV     A,#7
	RET
KEY_8:
	CJNE    A,#00101000B,KEY_9       
	MOV     A,#8
	RET
KEY_9:
	CJNE    A,#00100100B,KEY_A
	MOV     A,#9
	RET
KEY_A:
	CJNE    A,#00100010B,KEY_B
	MOV     A,#10
	RET
KEY_B:
	CJNE    A,#00100001B,KEY_C
	MOV     A,#11
	RET

KEY_C:
	CJNE    A,#00011000B,KEY_D
	MOV     A,#12
	RET
KEY_D:
	CJNE    A,#00010100B,KEY_E
	MOV     A,#13
	RET
KEY_E:
	CJNE    A,#00010010B,KEY_F
	MOV     A,#14
	RET
KEY_F:
	MOV     A,#15
	RET