I have a new board, that updated the processor from an 16F877 to a 18F45K22=
, porting the code over.
=20
However I ran across something that I haven't been able to really identify =
whats going on here. =20

This is a standard piece of code I use all the time with the 18F parts, and=
 up to  now I haven't seen any problems.

I'm using a ICD3 but not the latest version of MPLAB...its new enough to kn=
ow what this part is of course, and builds
Without any issues.  However I found that when I write to the EEPROM, data =
isn't getting in there so I put up a watch
Window and single stepped thru the code.

First off, the EEADR and EEDATA are not getting written to.

Next, the sequence of clearing and setting bits in the EECON1 register ..th=
is works.  The WREN bit gets set.

Then the magic sequence...doesnt get written to the EECON2 register

IF I push the values into the registers thru the watch window, indeed I can=
 get the values written to the
Desired address.

What I find interesting is setting an individual bit works, but moving a by=
te in..doesnt.

This routine works...Ive used it on several 18F parts, and verified in the =
data sheet..ie...the example code,=20
Is the same as well. =20

Any thoughts...why these SFR's are not being written to?  Has to be somethi=
ng simple but after looking at it and=20
Not seeing anything, just wonder if I am overlooking something ?



 EEPROM_WRITE
	BANKSEL EEADR
	movf	EEPROMaddr,w
 	movwf	EEADR
	movf	EEPROMdata,w
	movwf	EEDATA
	bcf	EECON1, EEPGD
	bcf	EECON1, CFGS
	bsf	EECON1, WREN
	bcf	INTCON,GIE		;disable interrupt
	movlw	0x55
	movwf	EECON2
	movlw	0xAA
	movwf	EECON2
	bsf	EECON1, WR
	bsf	INTCON,GIE		;re-enable interrupt - if interrupt is being used
eewait
	btfsc	EECON1,WR		;are we done? wait here till we are
	goto	eewait
	bcf	EECON1,WREN
	return

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--=20
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