cs24c64.asm

AT24C64通用源码

;NAME TXHC64
;?PR?TXHC64?TXHC64	SEGMENT CODE

TXHC64	SEGMENT CODE
	public	_write_eep_byte
	public	_read_eep_byte
	public	goto0000
	public	GotoISP

SDA		equ p1.0
SCL		equ p1.1


RSEG	TXHC64
_write_eep_byte:
	CLR	EA
	LCALL	ST24

	MOV		A,#0A0H
	LCALL	WBYTE
	JC		WRET
	MOV		A,R4
	ANL		A,#01FH

	LCALL	WBYTE
	JC		WRET
	MOV		A,R5
	LCALL	WBYTE
	JC		WRET
	MOV		A,R7			;tempbits
	LCALL	WBYTE
	LCALL	STOP24
	ACALL	DELAY_10MS
	CLR	C
WRET:
	SETB	EA
	RET
_read_eep_byte:
	CLR		EA
	LCALL	ST24

	MOV		A,#0A0H
	LCALL	WBYTE
	MOV		A,R6
	ANL		A,#1FH

	LCALL	WBYTE
	MOV		A,R7
	LCALL	WBYTE
	NOP
	LCALL	ST24

	MOV		A,#0A1H
	LCALL	WBYTE
	LCALL	RBYTE
	LCALL	STOP24
	MOV	R7,A
	
	SETB	EA
	RET

DELAY_1US:
	NOP
	NOP
	RET
DELAY_6US:
	ACALL	DELAY_1US
	RET

ST24:
	CLR	SCL
	LCALL	DELAY_6US
	SETB	SDA
	LCALL	DELAY_6US
	SETB	SCL
	LCALL	DELAY_6US
	CLR	SDA
	LCALL	DELAY_6US
	CLR	SCL
	LCALL	DELAY_1US
	RET

STOP24:
	CLR	SCL
	LCALL	DELAY_6US
	CLR	SDA
	LCALL	DELAY_6US
	SETB	SCL
	LCALL	DELAY_6US
	SETB	SDA
	LCALL	DELAY_6US
	CLR	SCL
	CLR	SDA
	RET

WBYTE:
	PUSH	B
	LCALL	DELAY_6US
	MOV	B,#8
WBY0:
	CLR	SCL
	RLC	A
	MOV	SDA,C
	LCALL	DELAY_6US
	SETB	SCL
	DJNZ	B,WBY0
	CLR	SCL
	LCALL	DELAY_6US
	SETB	SCL
	LCALL	DELAY_6US
	MOV	C,SDA
	CLR	SCL
	LCALL	DELAY_6US
	POP	B
	RET

RBYTE:
	PUSH	B
	LCALL	DELAY_6US
	MOV	B,#8
RBY0:
	CLR	SCL
	LCALL	DELAY_6US
	SETB	SCL
	LCALL	DELAY_6US
	MOV	C,SDA
	RLC	A
	DJNZ	B,RBY0
	CLR	SCL
	LCALL	DELAY_6US
	SETB	SDA
	LCALL	DELAY_6US
	SETB	SCL
	LCALL	DELAY_6US
	MOV	R7,A			;返回给C
	POP	B
	RET

DELAY_10MS:
	MOV	R7,#30
DE10:
	MOV	R6,#250
DE100:
	NOP
	NOP
	DJNZ	R6,DE100
	DJNZ	R7,DE10
	RET
;=================================================
goto0000:
	MOV     	DPTR,#HUI1      ;去除中断的激活标志
	PUSH    	DPL
	PUSH    	DPH
	RETI
HUI1:
	MOV		DPTR,#0
	PUSH    	DPL
	PUSH    	DPH
	RETI
GotoISP:
	CLR     EA
	LJmp    0FE00H     ;跳BOOT区

END