timer2 avr

[wn]

Having trouble. I need a 1 second time base timer. I am attempting to use timer2 on an AVR mega328. So far I think that the timer value for overflow needs to be set to 10800 with the oscillator being a 11.0592Mhz crystal. I am intializing with:

InitTimer2 Osc, PS_1024

I have a overflow handler like this:

sub idle_cntr()

sleep_cntr = sleep_cntr + 1
ser1send 10
ser1send 13
ser1print "TIMER 0 O/F"

ClearTimer 2
SetTimer 2, 10800
TMR2IF = 0

end sub

Currently it overflows much too quickly, way faster than 1 second.

[Anobium]

look in your installation for a nice set of timer help tools. There is a nice ZIP and one of the tools with help with the parameters.

..\GCB@Syn\GreatCowBasic\Demos\Interrupt_and_Timer_Solutions\Interrupt - Timed examples

[stan cartwright]

these values from timercalculator for 1000ms

  #chip mega328p,16
  #option explicit
  #define LED PORTB.4
  dir LED out
    ' Add the handler for the interrupt
    On Interrupt Timer1Match1 Call InterruptHandler
    ' Initialise the timer - this is required
    ' Set prescaler and then start the timer
    InitTimer1 Osc, PS_1_1
    ' Start the timer - this is required
    StartTimer 1
TCCR1A = 0x80;
TCCR1B = 0x0C;
OCR1AH = 0xF4;
OCR1AL = 0x23;

'Main routine
  Do
  Loop
  end
'This will be called when the Timer matches
Sub InterruptHandler
  LED = !LED
End Sub

[wn]

Thanks for the information. I will try these values. I also found the demos, which I has some how overlooked.