#include <SoftwareSerial.h>
const int buttonPin = 7;     // the number of the pushbutton pin
const int ledPin =  8;      // the number of the LED pin
SoftwareSerial mySerial(0, 1); // RX, TX

// Variables will change:
int ledState = HIGH;         // the current state of the output pin

void setup() {
  mySerial.begin(115200);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);
}

int cols[] = {97,98,99,100,101};
int selected = 0;
int BLOCK_TIME = 250;
int DEBOUNCE_TIME = 50;

void loop() {
  // read the state of the switch into a local variable:
  int reading = digitalRead(buttonPin);
  //button pressed
  if (reading == LOW) {
    delay(DEBOUNCE_TIME);
    if (reading == LOW) {
      selected = (selected + 1) % 5;
      mySerial.write(selected);
      if (ledState == HIGH)
        ledState = LOW;
      else
        ledState = HIGH;
      digitalWrite(ledPin, ledState);
      delay(BLOCK_TIME);
    }
  }
}