{{ ************************************
   *       demo_repeat_blink_led      *
   *       2008 Michael St.Onge       *
   ************************************

   Goal: Make a speaker output sound.

   Purpose: This will demonstrate simple frequency generation by sending pulses at a constant rate.
   
}}


CON

  _clkmode     = xtal1 + pll16x           ' Feedback and PLL multiplier
  _xinfreq     = 5_000_000                ' External oscillator = 5 MHz

  pinSpeaker   = 0                        ' assign which pin the led is on

  
PUB FreqGen                               ' Main method
 

  dira[pinSpeaker]~~                      ' Set pin to output (~ sets I/O to input and ~~ sets I/O to output, all pins default to input state)

  repeat                                  ' Endless loop

    !outa[pinSpeaker]                     'toggles output of pin low/high (if low, then high, or if high, then low)
 
    waitcnt(clkfreq / 4 + cnt)            ' Wait 1/4 second -> 2 Hz   (uses the clock frequency of 5 MHz)