#include <SoftwareSerial.h>
const int rx = PA0;
const int tx = PA1;
const int buttonPin = PA7; 
const int redLedPin = PA3;

int buttonState = 0;
int lastButtonState = 0;
int counter = 0;


SoftwareSerial mySerial(rx, tx);

void setup() {
  // put your setup code here, to run once:
    mySerial.begin(115200);
    pinMode(redLedPin, OUTPUT);
    pinMode(buttonPin, INPUT_PULLUP);

}

void loop() {
    // read the input pin:
  buttonState = digitalRead(buttonPin);
  if (buttonState !=lastButtonState){
    
    if (buttonState == LOW){
      counter++;
          mySerial.print("number of button pushes:  ");
          mySerial.println(counter);
          mySerial.println("");
      }

      delay(50);  
    }

    lastButtonState = buttonState;

    if(counter % 2 == 0){
        digitalWrite(redLedPin, HIGH);
     }else{
        digitalWrite(redLedPin, LOW);
        }
  
  delay(400);   

}