RK008 button input

#include <SendOnlySoftwareSerial.h.h>
#define MIDICHAN 15 // RK008 midi channel needs to be set to ch 16

// code from http://www.eddevane.com/blog/simple-midi-controller-with-attiny85
// adapted serial TX only lib to free up easy pin for midi current:
// https://github.com/nickgammon/SendOnlySoftwareSerial

// pinout
/*
                           --U--
             PB5 RST ---1-|     |-8---VCC (RK008 SYNC TIP)
             PB3 IN2 ---2-|     |-7 PB2 ---IN0
             PB4 IN1 ---3-|     |-6 PB1 ---TX --> 220ohm MIDI CURRENT
(RK008 SYNC GND) GND ---4-|     |-5 PB0 ---5v --> 220ohm MIDI SOURCE
                          ------

*/

// Variables:
byte cc = 0;
byte AnalogValue = 0; // define variables for the controller data
byte lastAnalogValue[3]; // define the "lastValue" variables
byte thresh = 8;// bigger value for switches instead of pots
byte ports[]={1,2,3}; // GPIO input ports
byte ccnumber[3] = {105,115,117}; // RK008 number for stop/play/rec CC
//software serial, pin RX(0) not used, we use hardware input
SendOnlySoftwareSerial midiSerial(1); // digital pins that we'll use for soft serial RX & TX

// Continuous Controller Function
void controlChange(byte ChannelByte,byte ControlNumber,byte ControlValue){
  midiSerial.write(ChannelByte + 0xb0);
  midiSerial.write(ControlNumber);
  midiSerial.write(ControlValue);
}

void setup() {
  //  launch MIDI serial port

  midiSerial.begin(31250);
  pinmode(0,OUTPUT);
  DDRB &= ~(1 << PB2); // Set the pin PB2 as input
  PORTB |= (1 << PB2);  //activate pull-up resistor for PB2
  DDRB &= ~(1 << PB3); // Set the pin PB3 as input
  PORTB |= (1 << PB3);  //activate pull-up resistor for PB3
  DDRB &= ~(1 << PB4); // Set the pin PB3 as input
  PORTB |= (1 << PB4);  //activate pull-up resistor for PB4

  DDRB |= (1 << PB0); // Set the pin PB0 as output
  PORTB |= (1 << PB0); //set PB0 to HIGH

}

void loop() {
  // read the 3 inputs
  for(int i = 0; i < 3; i++){
    cc = analogRead(ports[i])/8;
    if(abs(cc - lastAnalogValue[i]) > (thresh)) { // is there a difference beyond threshold?
      controlChange(MIDICHAN, ccnumber[i], cc); // send the CCs for stop/play/rec on midi channl #MIDICHAN
      lastAnalogValue[i] = cc;
    }
  }
}