On Mon, 21 May 2007 19:27:51 +0300, KPL wrote:

<snip>
>Here is part of the asm, for beginning I am reading only full degrees,
>so i take both data bytes, shift them 4 bits to leave integer only,
>and then decode and show it on old LED ascii display HDLU-1414.
>Program is based on routines from maxim application note 2420.
>May be somebody can see the error:)
>

One possibility for a problem come to mind:

Before doing those 4 'rlf' instructions on PICLSB, you should ensure
the the carry bit is cleared by using the pseudo-op 'clrc'. 

If the carry bit is set before those instructions are executed, bit 3
of PICLSB will be set when you don't expect it to be.

Regards, Bob


<snip>

>	rrf	PICMSB,F
>	rrf	PICMSB,F
>	rrf	PICMSB,F
>	rrf	PICMSB,F	;shift 4 bits R
>	movlw	15		;mask for 4 bits
>	andwf	PICMSB,F	;leaving 4 bits
>	andwf	PICLSB,F	;leaving 4 bits
>	rlf	PICLSB,F
>	rlf	PICLSB,F
>	rlf	PICLSB,F
>	rlf	PICLSB,F	;shift 4 bits left
>	movfw	PICLSB
>	xorwf	PICMSB,W	;join both bytes
>	
>	movwf	BIN
>	call BIN2BCD
>
>	bcf	testout
>	call	hpdl_out
>	call delay
>goto	req_conv
>
>
>
>-- 
>KPL

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