// Basic demo for configuring the MCP4728 4-Channel 12-bit I2C DAC
#include <Adafruit_MCP4728.h>
#include <Wire.h>

Adafruit_MCP4728 mcp;


int tuning[13];
int scale[] = { 0, 4, 7, 9, 12 };
float voltrange = 5.0;  // measured this, probably not accurate
float octave = 4096.0 / voltrange; // number of DAC steps in an octave

void setup(void) {
  Serial.begin(115200);
  while (!Serial)
    delay(10); // will pause Zero, Leonardo, etc until serial console opens

  if (!mcp.begin(0x64)) {
    Serial.println("Failed to find MCP4728 chip");
    while (1) {
      delay(10);
    }
    Serial.println("MCP4728 initialised");
  }

  Serial.println(octave);

  float n0 = 2048;
  for( int i = 0; i < 13; i++ ) {
      tuning[i] = round(n0 + octave * (float)i / 12);
      Serial.println(tuning[i]);
  }
  
}


void loop() {
  for( int i = 0; i < 5; i++ ) {
    mcp.setChannelValue(MCP4728_CHANNEL_A, tuning[scale[i]]);
    delay(200);
  }
}