On 4/07/2013 4:17 AM, Byron Jeff wrote:
> The interrupt handler is perfectly capable of doing the counting for
> you. Do you need a task that changes faster that 1S? If not, then there i=
s
> no need for counting anything in the main loop.
>
> I think your perceptual problem is that you are thinking of a system that
> remains in a physical location of code for a certain amount of time as
> opposed to an event/trigger based system that monitors a series of trigge=
rs
> and does an action when the trigger fires. When organized this way the ma=
in
> loop can handle several tasks that are triggered by different events.
That's right, I still can not see if there's tick in the background,
How can I use it, is it related with T0IF, yup I need the main loop to=20
handle several tasks controlled by interrupt.

I have created :
on main :

led_state_1

                 bsf      PORTB, POWERLED         ;Turn on LED
                 incf    LedState,1

                  movlw LedTimer                ;load the content of=20
LedTimer
                  movwf COUNT_TIMER           ;load the LedTimer into=20
file register


                 ;if COUNT_TIMER equal to 0 jump to the next state

                 return


is it like this on timer ?

;....... 1ms  timer counter here.....

                  clrf TMR0 ;Clear TMR0 and prescaler
                  banksel TMR0
                  movlw 0xB2 ;Count=3DB2
                  movwf TMR0

             timer1ms
               movf LedTimer,f
               btfsc STATUS,Z
               decf LedTimer,Z
          return

         ;....................................

         incf COUNT, f
         movlw  .10        ;Compare count to 10 decimal
         subwf COUNT, W        ;Store the result back in
         btfss STATUS, C        ;Is the result 0, skip if no
         goto exittimer

         clrf COUNT        ;Clear count register


Please correct me , thank you...

--=20
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