; *****************************************************************************
; This program shifts the display pattern of four seven-segment displays with 
; each pattern displayed for one second.
; Author: Dr. Han-Way Huang
; Date: January 5, 2005
; *****************************************************************************
#include "c:\miniide\hcs12.inc"
pat_port	equ	PORTB		; Port that drives the segment pattern
pat_dir	equ	DDRB		; direction register of the segment pattern
sel_port 	equ	PTP		; Port that select the digit
sel_dir	equ	DDRP		; direction register of the select port
		org	$1500
		movb	#$FF,pat_dir	; configure pattern port for output
		movb	#$3F,sel_dir	; configure digit select port for output
		ldx	#disp_tab		; use X as the pointer
first		ldab	#250
loop		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		decb
		beq	nxtLP1
		ldx	#disp_tab		; start from the begin of 0
		bra	loop
nxtLP1	ldab	#250
		ldx	#disp_tab+8
loop2		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		decb
		beq	nxtLP2
		ldx	#disp_tab+8		; start from the begin of 1 0
		bra	loop2
nxtLP2	ldab	#250
		ldx	#disp_tab+16
loop3		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		decb
		beq	nxtLP3
		ldx	#disp_tab+16	; reset to 2 1 0
		bra	loop3
nxtLP3	ldaa	#10
		ldx	#forever
loop41	ldab	#250	
loop42	movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		movb	1,x+,pat_port	; output the digit pattern
		movb	1,x+,sel_port	; output the digit select value
		ldy	#1			; wait for 1 ms
		jsr	delayby1ms		;	"
		decb
		beq	nxtLP4
		pshd
		tfr	x,d
		subd	#8
		tfr	d,x
		puld
		bra	loop42
nxtLP4	deca
		beq	nxtLP3
		jmp	loop41
#include	"c:\miniide\delay.asm"
; *****************************************************************
; seven-segment display table (pattern, digit select)
; *****************************************************************
disp_tab	dc.b	$3F,$FE,$00,$FD,$00,$FB,$00,$F7	; 0
		dc.b	$06,$FE,$3F,$FD,$00,$FB,$00,$F7	; 1 0
		dc.b	$5B,$FE,$06,$FD,$3F,$FB,$00,$F7	; 2 1 0
forever	dc.b	$4F,$FE,$5B,$FD,$06,$FB,$3F,$F7	; 3 2 1 0
		dc.b	$66,$FE,$4F,$FD,$5B,$FB,$06,$F7	; 4 3 2 1
		dc.b	$6D,$FE,$66,$FD,$4F,$FB,$5B,$F7	; 5 4 3 2
		dc.b	$7D,$FE,$6D,$FD,$66,$FB,$4F,$F7	; 6 5 4 3
		dc.b	$07,$FE,$7D,$FD,$6D,$FB,$66,$F7	; 7 6 5 4
		dc.b	$7F,$FE,$07,$FD,$7D,$FB,$6D,$F7	; 8 7 6 5
		dc.b	$6F,$FE,$7F,$FD,$07,$FB,$7D,$F7	; 9 8 7 6
		dc.b	$3F,$FE,$6F,$FD,$7F,$FB,$07,$F7	; 0 9 8 7
		dc.b	$06,$FE,$3F,$FD,$6F,$FB,$7F,$F7	; 1 0 9 8
		dc.b	$5B,$FE,$06,$FD,$3F,$FB,$6F,$F7	; 2 1 0 9
		end