ON 20080115@10:34:13 AM at page:
http://techref.massmind.org/techref/microchip/math/radix/a2b-3d8b-rw.htm#39461.3707638889
James Newton[JMN-EFP-786] removed post 39461.3707638889

|Delete '<A TITLE="P-194.201.250.209" NAME="39461.3707638889">
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<p>Hang on I'll try that again

<p>; This how I'd have done it as it saves having any loops - 18 clks
<p>; ASCII DIGIT1=(hundreds), DIGIT2=(tens), DIGIT3=(units). The hex value is in OUT.
<p>; The routine does not affect any of the ASCII DIGIT values, or need addition registers.
<p>; CAUTION: The routine does not test that the ASCII values are valid !
<p>; I have just written this code to show the idea, it hasn't been tested in anyway.  


<p>CONV_ASCII_HEX

<p>	movlw	0X0F		; Bit pattern to strip off ASCII offset 
<p>	andwf	DIGIT3, W 	; convert ASCII value to a number (units)
<p>	movwf	OUT, F		; start the running total (units)

<p>	rlf	DIGIT2, W	; read 2*DIGIT2 doing (tens)
<p>	andlw	0x1E		; clear ASCII offset + odd bits
<p>	addwf	OUT, F		; add to running total total 2T + U
<p>	addwf	OUT, F		; add to running total total 4T + U
<p>	addwf	OUT, F		; add to running total total 6T + U
<p>	addwf	OUT, F		; add to running total total 8T + U
<p>	addwf	OUT, F		; add to running total total 10T + U
	
<p>	movlw	'1'		; (Hundred) digit can only usefully be 1 or 2
<p>	subwf	DIGIT1, W	; test value of DIGIT1 (sets flags)
<p>	movlw	0x00		; clear value to add to total 
<p>	btfsc	STATUS, C	; test if result negative ie DIGIT1 was <='0'	 
<p>	movlw	200		; DIGIT1 was >'0', total needs inc by 100 or 200 
<p>	btfsc	STATUS, Z	; test if result = '1'
<p>	movlw	100		; DIGIT1 was = '1' inc total by 100
<p>	addwf	OUT, F		; add 0, 100 or 200 to total as req
<p>


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ON 20080115@10:34:48 AM at page:
http://techref.massmind.org/techref/microchip/math/radix/a2b-3d8b-rw.htm#
James Newton[JMN-EFP-786] edited the page. Difference:
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