.device AT90S8535
.equ    sph     =$3E
.equ    spl     =$3D
.equ    SREG	=$3F
.equ	PORTC	=$15 		
.equ	DDRC	=$14 		
.equ    PINC    =$13
.equ	PORTD	=$12 		
.equ	DDRD	=$11 		
.equ    PIND    =$10
.def 	ZL     	=r30
.def 	ZH     	=r31

	.org	$0000
	rjmp	main

main:	ldi	r16,$02			;棧指針置初值
	out	sph,r16
	ldi	r16,$5f
	out	spl,r16
	ldi	r16,$ff			;PC口定義為輸出口
	out	DDRC,r16
	out	PORTD,r16
	ldi	r16,$00			;PD口定義為輸入口
	out	DDRD,r16
start1:	ldi	r16,$ff			;定義無輸入時無輸出
	out	PORTC,r16
start:	in	r16,PIND		;讀PC口數(shù)據(jù)
	andi	r16,$1f			;取用PC口的低五位數(shù)據(jù)
	cpi	r16,$1f
	brne	shiy
	rjmp	start1
shiy:	mov	r17,r16
	rcall	de			;延時
	in	r16,PIND		;讀PC口的數(shù)據(jù)
	andi	r16,$1f			;取用PC口的低五位數(shù)據(jù)
	cpi	r16,$1f			;對P3口的低五位數(shù)據(jù)進行判斷
	brne	shiy1
	rjmp	start1			;開關(guān)沒有動作時無輸出
	
shiy1:	cp	r16,r17
	brne	start1
	cpi	r16,$17			;PC3=0時進入左轉(zhuǎn)分支
	brne	next1
	rjmp	left
	
next1:	cpi	r16,$0f			;PC4=0時進入右轉(zhuǎn)分支
	brne	next2
	rjmp	right
	
next2:	cpi	r16,$1d			;PC1=0時進入緊急分支
	brne	next3
	rjmp	earge
	
next3:	cpi	r16,$1e			;PC0=0時進入剎車分支
	brne	next4
	rjmp	brake

next4:	cpi	r16,$16			;PC3=0、PC0=0時進入左轉(zhuǎn)剎車分支
	brne	next5
	rjmp	lebr
	
next5:	cpi	r16,$0e			;PC4=0、PC0=0時進入右轉(zhuǎn)剎車分支
	brne	next6
	rjmp	ribr
	
next6:	cpi	r16,$1c			;PC1=0、PC0=0時進入緊急剎車分支
	brne	next7
	rjmp	brer

next7:	cpi	r16,$14			;PC3=0、PC1=0、PC0=0時進入左轉(zhuǎn)緊急剎車分支
	brne	next8
	rjmp	lbe
	
next8:	cpi	r16,$0c			;PC4=0、PC1=0、PC0=0時進入右轉(zhuǎn)緊急剎車分支
	brne	next9
	rjmp	rbe
	
next9:	cpi	r16,$1b			;PC2=0時進入停靠分支
	brne	next10
	rjmp	stop
	
next10:	rjmp	error			;其他情況進入錯誤分支

left:	ldi	r16,$6a			;左轉(zhuǎn)分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$ff	
	out	PORTC,r16
	rcall	de1s
	rjmp	start
	
right:	ldi	r16,$55			;右轉(zhuǎn)分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$ff	
	out	PORTC,r16
	rcall	de1s
	rjmp	start

earge:	ldi	r16,$40			;緊急分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$ff	
	out	PORTC,r16
	rcall	de1s
	rjmp	start

brake:	ldi	r16,$4f			;剎車分支
	out	PORTC,r16
	rjmp	start
	
lebr:	ldi	r16,$4a			;左轉(zhuǎn)剎車分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$5f	
	out	PORTC,r16
	rcall	de1s
	rjmp	start
	
ribr:	ldi	r16,$45			;右轉(zhuǎn)剎車分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$6f	
	out	PORTC,r16
	rcall	de1s
	rjmp	start
	
brer:	ldi	r16,$40			;緊急剎車分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$4f	
	out	PORTC,r16
	rcall	de1s
	rjmp	start
	
lbe:	ldi	r16,$40			;左轉(zhuǎn)緊急剎車分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$5f	
	out	PORTC,r16
	rcall	de1s
	rjmp	start
	
rbe:	ldi	r16,$40			;右轉(zhuǎn)緊急剎車分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$6f	
	out	PORTC,r16
	rcall	de1s
	rjmp	start
	
stop:	ldi	r16,$43			;停靠分支
	out	PORTC,r16
	rcall	de100ms
	ldi	r16,$7f	
	out	PORTC,r16
	rcall	de100ms
	rjmp	start

error:	ldi	r16,$3f			;錯誤分支
	out	PORTC,r16
	rcall	de1s
	ldi	r16,$ff	
	out	PORTC,r16
	rcall	de1s
	rjmp	start

de:	ldi	r24,6			;延時子程序
	push	r24
del2:	push	r24
del3:	dec	r24
	brne	del3
	pop	r24
	dec	r24
	brne	del2
	pop	r24
	ret
	
de1s:	ldi	r24,249
	push	r24
desl1:	push	r24
desl2:	push	r24
desl3:	dec	r24
	brne	desl3
	pop	r24
	dec	r24
	brne	desl2
	pop	r24
	dec	r24
	brne	desl1
	pop	r24
	ret
	
de100ms:ldi	r24,114
	push	r24
demsl1:	push	r24
demsl2:	push	r24
demsl3:	dec	r24
	brne	demsl3
	pop	r24
	dec	r24
	brne	demsl2
	pop	r24
	dec	r24
	brne	demsl1
	pop	r24
	ret