#include <BlockNot.h>

#define ENCODER_PIN_A PB0
#define ENCODER_PIN_B PB1

BlockNot nonblockingTimer(5); // 5ms nonblocking timer

volatile long encoderValue = 0;

void setup() {
 pinMode(ENCODER_PIN_A, INPUT_PULLUP);
 pinMode(ENCODER_PIN_B, INPUT_PULLUP);
 attachInterrupt(digitalPinToInterrupt(ENCODER_PIN_A), encoderInterrupt, CHANGE);
 attachInterrupt(digitalPinToInterrupt(ENCODER_PIN_B), encoderInterrupt, CHANGE);
 Serial.begin(115200);
}

void loop() {
  if (nonblockingTimer.TRIGGERED) {
    encoderInterrupt();
  } 
}

void encoderInterrupt() {
 static int lastMSB = digitalRead(ENCODER_PIN_A);
 int MSB = digitalRead(ENCODER_PIN_A);
 int LSB = digitalRead(ENCODER_PIN_B);
 if (MSB != lastMSB) {
    if (MSB == LSB) {
      encoderValue++;
      Serial.println("> Encoder++");
    } else {
      encoderValue--;
      Serial.println("> Encoder--");
    }
 }
 lastMSB = MSB;
}