eewrite.asm

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;############################################
;# PROCEDURY pro zapis do EEPROM procesoru  #
;############################################
;
	.global	eewritea
	.global	eewrite
;
.nolist
.include "param.inc"
.list
;
	.text
;
; input: R2(A) - data
;	 dptr  - address
;
;	WARNING - OFF EEPROM
;
eewritea:
	mov	r2,a
eewrite:
.if	RD2
	ENABLE_EE
	movx	a,@dptr		;read eeprom
	xrl	a,r2
	jz	Lnowr		;no need change, bypas write
	mov	a,r2
	mov	EETIM, #EEDLY
	movx	@dptr,a		;write
	mov	R2, IE		; save IE
	clr	EA		; disable all interrupts
	mov	EECON, #0x50	; Write Sequence
	mov	EECON, #0xA0
	mov	IE, R2		; restore IE
Lwait:	mov	A, EECON	;wait for end of write
	jb	Acc.0, Lwait
.else
	orl	WMCON,#(EEMEN | EEMWE) ;enable R/W EEPROM
	movx	a,@dptr		;read eeprom
	xrl	a,r2
	jz	Lnowr		;no need change, bypas write
	mov	a,r2
	movx	@dptr,a		;write
Lwait:	movx	a,@dptr		;wait for end of write
	xrl	A,r2
	jnz	Lwait
.endif
Lnowr:	DISABLE_EE
	ret