at24c08.asm

MCS-51单片机实验 39个实用实验和源码

;****************************************************************
;文件名称:AT24C08.ASM						*
;先将数据30H、31H、32H、... 3FH写入到24C08地址00～0FH空间中去;	*
;再将24C08地址空间00～0FH的数据读到内部RAM的40~47H空间中来。	*
;***************************************************************
	SCL 	EQU P1.0
	SDA 	EQU P1.1
	ORG 	0000H
	SJMP	MAIN
	ORG 	0030H
MAIN:
	MOV 	R6,#10H		;写24C08，共写16个
	MOV 	R0,#30H		;写"0"..."F"
	ACALL 	W_DATA
W_LOOP0:
	INC  	R0
	DJNZ 	R6,W_LOOP1
	SJMP 	W_END
W_LOOP1:
	ACALL 	W_DATA1
	SJMP 	W_LOOP0
W_END:	
	ACALL 	STOP24
	ACALL 	DELAY

RD_EEROM:		       ;读24C08
	MOV 	R6,#10H
	MOV 	R1,#40H    ;存放数据的起始地址
	ACALL 	R_DATA
R_LOOP0:
	MOV     @R1,A
	INC     R1
	DJNZ 	R6,R_LOOP1
	ACALL 	STOP24
	SJMP 	$         ;可在此设断点，程序运行到此处，查看内部数据窗口
R_LOOP1:
	ACALL 	R_DATA1
	SJMP	R_LOOP0
;-------------------------------------
W_DATA:
	ACALL 	START24
	MOV 	A,#0A0H		;写命令
	ACALL 	WBYTE

	CLR 	A		    ;写起始地址，地址自动加1
	ACALL 	WBYTE
W_DATA1:
	MOV 	A,R0		;写数据
	ACALL 	WBYTE
	RET
;-------------------------------------
R_DATA:	
	ACALL 	START24
	MOV 	A,#0A0H		;写命令
	ACALL 	WBYTE
	CLR 	A	    	;写起始地址，地址自动加1
	ACALL 	WBYTE
R_DATA1:
	ACALL 	START24
	MOV 	A,#0A1H		;读命令
	ACALL 	WBYTE
	ACALL 	RBYTE		;读数据
	RET
;-------------------------------------
WBYTE:
	NOP
	MOV 	R3,#08H
WBY0: 
	CLR 	SCL
	RLC 	A
	MOV 	SDA,C
	SETB 	SCL
	DJNZ 	R3,WBY0
	CLR 	SCL
	NOP
	SETB 	SCL
	NOP
	JB 	    SDA,$
	CLR 	SCL
	NOP
	RET
;------------------------------------------
RBYTE:
	NOP
	MOV 	R3,#08H
RBY0:
	CLR 	SCL
	NOP
	SETB 	SCL
	NOP
	MOV 	C,SDA
	RLC 	A
	DJNZ 	R3,RBY0
	CLR 	SCL
	NOP
	SETB 	SDA
	NOP
	SETB 	SCL
	RET

;---------------------------------
START24:
	CLR 	SCL
	NOP
	SETB 	SDA
	NOP
	SETB 	SCL
	NOP
	CLR 	SDA
	NOP
	CLR 	SCL
	RET
;---------------------------------
STOP24:
	CLR 	SCL
	NOP
	CLR 	SDA
	NOP
	SETB 	SCL
	NOP
	SETB SDA
	NOP
	CLR SCL
	RET
;---------------------------------
DELAY:  MOV     R0,#0H          ;延时子程序
DELAY1: MOV     R1,#0H
        DJNZ    R1,$
        DJNZ    R0,DELAY1
        RET
END