Signal Combination

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Signal Functions or signal inputs can be easily combined.

The following Signal Function shows how to invoke several signals so that they are processed in order.

//
// Combine the Signals
//
signal void Startup (void)  {
  swatch (1.0);    // wait 1.0 seconds
  ADC0_Saw ();
  swatch (0.3);    // wait 0.3 seconds
  ADC0_Square ();
  swatch (0.6);    // wait 0.6 seconds
  ADC0_Sine ();
}

The Signal Function above setting generates the following output.

It is even possible to mix two sine wave signals as shown with the Signal Function below.

/*
 * Generate a Sine Wave Input
 */
signal void mix_sine (float freq1, float freq2)  {
  float sig1;
  float sig2;
  int z;

  z = 0;

  while (z < 10000)  {   // generate 100 mSec sine wave pulse
/* Generate 1. Sine Wave input signal*/
    sig1 = __sin (((states * freq1) / CLOCK) * 3.1415926 * 2);

/* Generate 2. Sine Wave input signal */
    sig2 = __sin (((states * freq2) / CLOCK) * 3.1415926 * 2);

/* Input: 1. Sine Wave with 0.5V, 2. Sine Wave with 0.2V, offset 2.5V */
    AN0 =  (sig1 * 0.5) + (sig2 * 0.2) + 2.5;
    swatch (0.00001);    // wait 10 uSec
    z++;
  }
}

This Signal Function may be directly invoked from the command line to generate two frequencies. For example the invocation:

mix_sine (300, 2000)

generates an input signal with 300Hz and 0.5V amplitude and 2000Hz and 0.2V amplitude and an offset of 2.5V. The Logic Analyzer window below shows this signal.