Programming:Display a 8-bit number in hex - Revision history

Kevindb at 15:24, 20 January 2015

2015-01-20T15:24:51Z

@@ Line 42: / Line 42: @@
                  ;;become "A"...."F"
 .number
 jp txt_output   ;display digit
 </pre>
 [[Category:Programming]]

Octoate: added category

2007-03-12T16:05:31Z

added category

← Older revision		Revision as of 16:05, 12 March 2007
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	jp txt_output ;display digit		jp txt_output ;display digit
	</pre>		</pre>

			[[Category:Programming]]

CPCLER at 15:43, 12 March 2007

2007-03-12T15:43:36Z

← Older revision		Revision as of 15:43, 12 March 2007
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			From the '''The Unofficial Amstrad WWW Resource''':

			This routine uses [[Firmware]]

	<pre>		<pre>
	;; A procedure to display a 8-bit number in hex form		;; A procedure to display a 8-bit number in hex form

CPCLER at 15:18, 12 March 2007

2007-03-12T15:18:24Z

New page

<pre>
;; A procedure to display a 8-bit number in hex form
;;
.txt_output equ &bb5a

;;----------------------------
;; DISPLAY A BYTE IN HEX FORM
;;
;; Enter:
;; A = 8-bit value
;;
;; Exit:
;; AF corrupt, All other registers preserved

.print_hex_byte
push af ;store original byte value

;; move upper nibble into lower nibble
rrca
rrca
rrca
rrca

;; display nibble as ASCII
call print_byte_digit
pop af ;retrieve original byte value

;;-------------------------------------------
;; display number in lower nibble (bits 3..0)
.print_byte_digit
and %00001111 ;isolate lower nibble. (This contains the digit value 0...15)
add a,"0" ;add ASCII for 0. Digits 0...9 become "0"..."9", digits 10..15
;become ":"...."A"
cp "9"+1
jr c,number ;if number is in digit range 0...9, display digit

add a,"A"-"9"-1 ;modify ASCII value so that digits in the range 10...15
;;become "A"...."F"
.number
jp txt_output ;display digit
</pre>