Es läuft auf der neuesten Version mit Erweiterungskarte v2.1a

Pycom MicroPython 1.18.2.r4 [v1.8.6-849-ba178ae] am 2019-04-01; WiPy mit ESP32

from machine import I2C
#import array
import time
#import binascii
import math

#Init bus
#remove jumper from led
#SDA=P9 aka G16 aka GPIO12  SCL=P10 aka G17 aka GPIO13
#expansionboard v2.1a
i2c = I2C(0, I2C.MASTER,  baudrate=100000)

i2c.scan()

i2cadr = 0x40
A = 8.1332;
B = 1762.39;
C = 235.66

def crc8(raw):
  check = raw[0] << 16 | raw[1] << 8 | raw[2]
  #print(check)
  #print(raw[0], ' ', raw[1], ' ', raw[2])

  check1 = check

  divsor = 0x988000 # 1 0011 0001 0x131

  for i in range(0, 16):
    if( check & 1 << (23 - i) ):
      check ^= divsor

    divsor = divsor >> 1

  if not check == 0:
    #print('True')
  #else:
    print('False')


while 1:
  ## read Temperature, hold
  #i2c.writeto(i2cadr, b'\xE3')
  ## read Temperature, no hold
  dummy = i2c.writeto(i2cadr, b'\xF3')
  time.sleep(0.1)
  raw = i2c.readfrom(i2cadr, 3)

  crc8(raw)
  raw = raw[0] << 8 | raw[1]
  #raw = raw & 0xFFFC;
  #tempV = -46.85 + (175.72 * raw / 65536)
  raw = raw >> 2;
  tempV = -46.85 + (175.72 * raw / 16384)

  ## read Humidity, hold
  #i2c.writeto(i2cadr, b'\xE5')
  ## read Humidity, no hold
  dummy = i2c.writeto(i2cadr, b'\xF5')
  time.sleep(0.1)
  raw = i2c.readfrom(i2cadr, 3)
  raw = raw[0] << 8 | raw[1]	
  #raw = raw & 0xFFFC;
  #humdV = -6 + (125.0 * raw / 65536)
  raw = raw >> 2;
  humdV = -6 + (125.0 * raw / 16384)

  ## compute dewpoint
  pp = math.pow(10, A - B / (tempV + C))  
  tm = math.log(humdV * pp / 100, 10)
  dp = -(B / (tm - A) + C)

  #print('temp: ', tempV, '  relH: ', humdV,' dew: ',dp)
  print('temp: {:<10} relH: {:<10} dew: {:<10}'.format(tempV, humdV, dp))
  time.sleep(2)