timer0 experiment.asm

.INCLUDE "TN85DEF.INC"   ;ATTINY13 DEFINITIONS
	.DEF A = R16             ;GENERAL PURPOSE ACCUMULATOR

	.ORG 0000
	ON_RESET:
	    SBI DDRB,0           ;SET PORTB0 FOR OUTPUT
	    LDI A,0b0000_0001    ;SET TIMER PRESCALER TO /1024
	    OUT TCCR0B,A

	MAIN_LOOP:
	      SBI   PINB,0       ;FLIP THE 0 BIT
	      RCALL PAUSE        ;WAIT
	       RJMP MAIN_LOOP    ;GO BACK AND DO IT AGAIN

	PAUSE:
	PLUPE: IN   A,TIFR        ;WAIT FOR TIMER
	       ANDI A,0b0000_0010  ;(TOV0)
	        BREQ PLUPE
	       LDI  A,0b0000_0010  ;RESET FLAG
	       OUT  TIFR,A        ;NOTE: WRITE A 1 (NOT ZERO)
	        RET
;-----------------------------------------------------------------------------------------------------
.INCLUDE "TN85DEF.INC"   ;ATTINY13 DEFINITIONS
        .DEF A = R16             ;GENERAL PURPOSE ACCUMULATOR

        .ORG 0000
        ON_RESET:
            SBI DDRB,0           ;SET PORTB0 FOR OUTPUT
            LDI A,0b0000_0001    ;SET TIMER PRESCALER TO /1024
            OUT TCCR0B,A

        MAIN_LOOP:
              SBI   PINB,0       ;FLIP THE 0 BIT
              RCALL PAUSE        ;WAIT
               RJMP MAIN_LOOP    ;GO BACK AND DO IT AGAIN

        PAUSE:
        PLUPE: IN   A,TIFR        ;WAIT FOR TIMER
               ANDI A,0b0000_0010  ;(TOV0)
                BREQ PLUPE
               LDI  A,0b0000_0010  ;RESET FLAG
               OUT  TIFR,A        ;NOTE: WRITE A 1 (NOT ZERO)
                RET
waitForInPinHigh:
	sbic PORTB,2
	rjmp waitForInPinHigh
	ret
waitForInPinLow:
	sbis PORTB,2
	rjmp waitForInPinLow
	ret
startTimer:
	LDI A,0b0000_0001    ;SET TIMER PRESCALER TO /1024
    OUT TCCR0B,A
ret
timerLoop:
	IN   A,TIFR        ;WAIT FOR TIMER
    ANDI A,0b0000_0010  ;(TOV0)
    BREQ timerLoop
    LDI  A,0b0000_0010  ;Push TOVO back down.RESET FLAG
    OUT  TIFR,A        ;NOTE: WRITE A 1 (NOT ZERO)
	;if key pressed get out of loop and stop
	inc r18
	brne timerLoop
	inc r19
	brne timerloop
	inc r20
	rjmp timerloop

RET
stopTimer:
	LDI A,0b0000_000    ;SET TIMER PRESCALER TO /1024
    OUT TCCR0B,A
ret