SWRMeter/firmware/waveformgenerator.ino

#include "Waveforms.h"

#define PWM_BIT_WIDTH 8
#define PWM_PIN       5 // PWM-Pin für DAC0 auf dem Arduino Nano 328

uint8_t  wf_wave0 = 0;
uint8_t  wf_pos   = 0;
uint16_t wf_freq  = 0;

unsigned long wf_sample_us  = 0;
unsigned long wf_prevMicros = 0;

bool wf_outputEnabled = true;  // Variable to control waveform output state

void initWaveformGenerator()
{
  pinMode(PWM_PIN, OUTPUT);
  setWaveform(WAVEFORM_SINUS);
  // Call the function to set default frequency, here you might want to specify a default frequency
  setWaveformFrequency(WAVEFORM_DEFAULT_FREQ_HZ);
}

void setWaveform(uint8_t waveform0)
{
  if (waveform0 >= 0 and waveform0 < WAVEFORM_MAXWAVEFORM_NUM)
  {
    // Set default waveforms
    wf_wave0 = waveform0;
  } else {
    wf_wave0 = WAVEFORM_SINUS;
  }
}

void setWaveformFrequency(uint16_t frequency)
{
  if (frequency >= 1 and frequency < 8000)
  {
    wf_freq = frequency;
  } else {
    wf_freq = WAVEFORM_DEFAULT_FREQ_HZ;
  }
  wf_sample_us = 1000000UL / ((unsigned long)wf_freq * WAVEFORM_MAX_SAMPLES_NUM);
}

void enableWaveformOutput()
{
  wf_outputEnabled = true;
}

void disableWaveformOutput()
{
  wf_outputEnabled = false;
}

void pollWaveformGenerator()
{

  if (wf_outputEnabled)
  {
    unsigned long currentMicros = micros();  // Aktuelle Zeit abrufen
    if (currentMicros - wf_prevMicros >= wf_sample_us)
    {
        wf_prevMicros = currentMicros;

        uint16_t sample = map(waveformsTable[wf_wave0][wf_pos], 0, 0xfff, 0, (1 << PWM_BIT_WIDTH)-1);
        sample = constrain(sample, 0, (1 << PWM_BIT_WIDTH)-1);
        analogWrite(PWM_PIN, sample);  // write the selected waveform on DAC0
        // analogWrite(PWM_PIN, 128);  // write the selected waveform on DAC0

        wf_pos++;
        if (wf_pos == WAVEFORM_MAX_SAMPLES_NUM)  // Reset the counter to repeat the wave
            wf_pos = 0;

    }
  } else {
        analogWrite(PWM_PIN, 0);
  }
}