;Senior Design

.EQU	COUNT,00H
.EQU	DELAY,10H
.EQU	SPEED,20H

	MOV	TMOD,#01H	;TIMER 0,  MODE 1
	MOV	COUNT,#00	;CLEAR COUNT VALUE
	MOV	SPEED,#00	;CLEAR SPEED VALUE
	MOV	DELAY,#05H	;.22SEC DELAY FIVE TIMES

BEGIN:
	MOV	TL0,#00H	;INITIALIZE TIMER 0 
	MOV	TH0,#00H	;FOR 1 SECOND DELAY

	SETB	TR0		;STARTS TIMER

	MOV	A,P3.2		;READS PORT PIN 3.2 FOR INPUT
	JNZ	ADDONE		;IF PIN IS "HI" JUMP TO ADDONE

PAUSE:	JNB	TF0,PAUSE	
	CLR	TFO	
	CLR	TR0	
	DJNZ	DELAY,BEGIN	;JUMP TO BEGIN UNTIL DELAY IS ZERO 
	SJMP	DISPLAY		;JUMP TO DISPLAY WHEN 1 SECOND IS DONE

ADDONE:
	MOV	A,COUNT		;MOVES COUNT INTO THE ACC
	ADD	A,#01H		;ADDS 1 TO THE COUNT
	DA	A		;DECIMAL ADJUST
	MOV	COUNT,A		;STORES THE VALUE IN COUNT
	RETI			;RETURN
	
DISPLAY:
	MOV	A,COUNT		;MOVES COUNT INTO THE ACC
				;TO DIVIDE BY 2.2 FOR THE SPEED I JUST
				;DIVIDE BY 22 AND THEN MULTIPLY BY 10
	MOV	B,#16H		;PLACES 16h (22d) IN B
	DIV	AB		;DIVIDES THE COUNT BY 22	
	MOV	B,#0AH		;PLACES 0Ah (10d) IN B
	MUL	AB		;MULTIPLIES BY 10
	MOV	SPEED,A		;STORES THE SPEED
	MOV	P1,SPEED	;OUTPUTS THE SPEED TO PORT 1
	MOV	COUNT,#00H	;RESETS THE COUNT TO ZERO
	MOV	DELAY,#05H	;RESETS THE TIMER
	SJMP	BEGIN
.END