Signal generator v1.5

/*
 * ApplySignal.ino
 * 2018 WLWilliams
 *
 * Basic Signal Generator v1.5
 * Learnelectronics
 * Aug 17 2020
 * www.youtube.com/learnelectronics
 * arduino0169@gmail.com
 *
 * Library code found at: https://github.com/Billwilliams1952/AD9833-Library-Arduino
 *
 */
#include <Wire.h>                                                       //I2c library for the OLED display
#include <Adafruit_SSD1306.h>                                           //OLED driver

#define OLED_RESET 4                                                    //necessary for the OLED
#include <AD9833.h>                                                     // Include the library

#define FNC_PIN 5                                                       // Can be any unused digital IO pin


AD9833 gen(FNC_PIN);                                                    // Defaults to 25MHz internal reference frequency

Adafruit_SSD1306 display(OLED_RESET);                                   // create object for the OLED

int rate = 100;                                                         //inital rate of sig gen
int pot = 0;                                                            //initial value for potentiometer
const int  buttonPin = 8;                                               //waveform switch on pin 8
int buttonPushCounter = 0;                                              //count how many times the button has been pushed
int buttonState = 0;                                                    //is the button high or low
int lastButtonState = 0;                                                //remember the last state



void setup() {

    gen.Begin();                                                        // This MUST be the first command after declaring the AD9833 object

                                                                        // Apply a 1000 Hz sine wave using REG0 (register set 0). There are two register sets,
                                                                        // REG0 and REG1.
                                                                        // Each one can be programmed for:
                                                                        //   Signal type - SINE_WAVE, TRIANGLE_WAVE, SQUARE_WAVE, and HALF_SQUARE_WAVE
                                                                        //   Frequency - 0 to 12.5 MHz
                                                                        //   Phase - 0 to 360 degress (this is only useful if it is 'relative' to some other signal
                                                                        //           such as the phase difference between REG0 and REG1).
                                                                        // In ApplySignal, if Phase is not given, it defaults to 0.
    gen.ApplySignal(SINE_WAVE,REG0,rate);                               //start up the sig gen

    gen.EnableOutput(true);                                             // Turn ON the output - it defaults to OFF


    pinMode(A0,INPUT);                                                  //set up analog0 to read the pot
    pinMode(8,INPUT_PULLUP);                                            //set up dig 8 for input with internal pullup

    Serial.begin(9600);                                                 //start serial comms for debugging
    display.begin(SSD1306_SWITCHCAPVCC, 0x3C);                          //start up OLED
  display.display();                                                    //show display buffer

  display.clearDisplay();                                               //clear OLED
}

void loop() {

buttonState = digitalRead(buttonPin);                                   //digital read of pin8
pot = analogRead(A0);                                                   //analog read of A0
rate = map(pot, 0, 1023, 1000, 10000);                                  //map the value of the analog read to frequencies

if (buttonState != lastButtonState) {
                                                                        // if the state has changed, increment the counter
    if (buttonState == HIGH) {
                                                                        // if the current state is HIGH then the button went from off to on:
      buttonPushCounter++;
      Serial.println("on");
      Serial.print("number of button pushes: ");
      Serial.println(buttonPushCounter);

    } else {
                                                                        // if the current state is LOW then the button went from on to off:
      Serial.println("off");
    }
                                                                        // Delay a little bit to avoid bouncing
    delay(50);
  }
                                                                        // save the current state as the last state, for next time through the loop
  lastButtonState = buttonState;
if (buttonPushCounter > 2){
  buttonPushCounter = 0;                                                //reset the number of button pushes
}

  display.setTextSize(2);                                               //send freq & wave type to OLED buffer
  display.setTextColor(WHITE);
  display.setCursor(0,0);
  display.clearDisplay();
  display.print("Freq:");
  display.println(rate);
  display.println("");
  display.print("Type:");

  switch (buttonPushCounter) {                                          //determine which waveform to output
    case 1:
      display.print("Sine");
      gen.ApplySignal(SINE_WAVE,REG0,rate);                             //output desired waveform
      break;
    case 2:
      display.print("Tri");
      gen.ApplySignal(TRIANGLE_WAVE,REG0,rate);                         //output desired waveform
      break;
    case 3:
      display.print("Squar");
      gen.ApplySignal(SQUARE_WAVE,REG0,rate);                           //output desired waveform
    break;
    default:
      display.print("Squar");
      gen.ApplySignal(SQUARE_WAVE,REG0,rate);                           //if it gets out of sorts just do this
    break;
  }
  display.display();                                                    //show whats in the OLED buffer

  //gen.ApplySignal(SINE_WAVE,REG0,rate);




}