/*
  ESP32 DAC  Oscilloscope Art Demo
  espdac-scope-art.ino
  Generates pattern on oscilloscope
  Scope must be in X-Y mode
  Original scope code by Bitluni - https://github.com/bitluni/OsciDisplay/
 
  DroneBot Workshop 2022
  https://dronebotworkshop.com
*/

// Include DAC and Math Libraries
#include <driver/dac.h>
#include <math.h>

// Define variable for increment
float t = 0;

void setup() {
  // Enable both DAC channels
  dac_output_enable(DAC_CHANNEL_1);
  dac_output_enable(DAC_CHANNEL_2);
}


void loop() {
  // Move two channels through sine and cosine waves

  // Increment variable
  t += 0.01;

  // Step through circle
  for (float f = 0; f < M_PI * 2; f += 0.01) {
    dac_output_voltage(DAC_CHANNEL_1, sin(f) * 120 + 120);
    dac_output_voltage(DAC_CHANNEL_2, cos(f + t) * 120 + 120);
  }

  // Send DAC output HIGH to provide scope trigger on both channels
  dac_output_voltage(DAC_CHANNEL_1, 255);
  dac_output_voltage(DAC_CHANNEL_2, 255);

  // Short delay
  delay(10);
}