EncoderTimer, der Anfang

#include <Arduino.h>

#define EncPin1 19
#define EncPin2 23

volatile int8_t interruptCounter;
long int EncoderCounter;

hw_timer_t *timer = NULL;
portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;

const int8_t table[16] PROGMEM = {0,0,-1,0,0,0,0,1,1,0,0,0,0,-1,0,0};

void IRAM_ATTR Encoder();
int8_t encode_read();

void setup()
{

  Serial.begin(115200);

  pinMode(EncPin1, INPUT_PULLUP);
  pinMode(EncPin2, INPUT_PULLUP);

  timer = timerBegin(0, 80, true);
  timerAttachInterrupt(timer, &Encoder, true);
  timerAlarmWrite(timer, 3000000, true);
  timerAlarmEnable(timer);
}

void loop()
{
  EncoderCounter += encode_read();
}

void IRAM_ATTR Encoder()
{
  static int8_t last = 0;
  int8_t EncVal1 = digitalRead(EncPin1);
  int8_t EncVal2 = digitalRead(EncPin2);
  last = (last << 2) & 0x0F;
  if (EncVal1 == HIGH)
    last |= 1;
  if (EncVal2 == HIGH)
    last |= 2;

  interruptCounter += pgm_read_byte(&table[last]);
  Serial.println(last, BIN);
  Serial.println(EncoderCounter);
}

int8_t encode_read(void)
{ // Encoder auslesen
  int8_t val;

  // atomarer Variablenzugriff
  cli();
  val = interruptCounter;
  interruptCounter = 0;
  sei();
  return val;
}