Hitechnic Compass sensor with BrickPi3

BrickPi
1

I wnat to use the Hitechnic Compass sensor with the BirckPi3. I have written a class to use it. But I get only Numbers between 206 and 160 from the Compass. What is wrong?

#!/usr/bin/python
########################################
# class hitechnic compass              #
# file: HitechnicCompassSensor.py      #
# Author: Th. Kaffka, Cologne, Germany #
# Date: 10.11.2020                     #
########################################
import brickpi3
import time

BP = brickpi3.BrickPi3()

class HitechnicCompassSensor:

   I2C_ADR = 0b00000010
   GET_DIR = 0x42

   COMMAND = 0x41
   BEGIN_CALIBRATION = 0x43
   END_CALIBRATION = 0x00

   def __init__(self, port):
      self.port = port
      BP.set_sensor_type(port, BP.SENSOR_TYPE.I2C, [0, 20])
   
   def getDirection(self):
      # compass intervall 160, 206
      BP.transact_i2c(self.port, self.I2C_ADR, [self.GET_DIR], 2)
      time.sleep(0.01)
      value = BP.get_sensor(self.port)
      return ((value[0] & 0xFF) << 1) + value[1]
    
   def startCalibration (self):
      BP.transact_i2c(self.port, self.I2C_ADR, [self.COMMAND, self.BEGIN_CALIBRATION], 0)
      time.sleep(0.01)

   def endCalibration (self):
      BP.transact_i2c(self.port, self.I2C_ADR, [self.COMMAND, self.END_CALIBRATION], 0)
      time.sleep(0.01)