1  import time
 2  import board
 3  import busio
 4  from analogio import AnalogIn
 5  import adafruit_ds1841
 6  
 7  # WIRING:
 8  # 1 Wire connecting  VCC to RH to make a voltage divider using the
 9  #   internal resistor between RH and RW
10  # 2 Wire connecting RW to A0
11  def wiper_voltage(_wiper_pin):
12      raw_value = _wiper_pin.value
13      return raw_value / (2 ** 16 - 1) * _wiper_pin.reference_voltage
14  
15  
16  i2c = busio.I2C(board.SCL, board.SDA)
17  ds = adafruit_ds1841.DS1841(i2c)
18  
19  
20  LUT_MAX_INDEX = 71
21  WIPER_MAX = 127
22  wiper_pin = AnalogIn(board.A0)
23  
24  ds.lut_mode_enabled = True
25  
26  # you only need to run this once per DS1841 since the LUT is stored to EEPROM
27  # for i in range(0, LUT_MAX_INDEX+1):
28  #     new_lut_val = WIPER_MAX-i
29  #     ds.set_lut(i, new_lut_val)
30  
31  while True:
32      for i in range(0, LUT_MAX_INDEX + 1):
33          ds.lut_selection = i
34          # for printing to serial terminal:
35          print(
36              "\tLUTAR/LUT Selection: %s" % hex(ds.lut_selection),
37              "\tWiper = %d" % ds.wiper,
38              "\tWiper Voltage: %f" % wiper_voltage(wiper_pin),
39          )
40          time.sleep(0.5)
41  
42          # uncomment this and comment out the above to print out a mu plotter friendly format (tuple)
43          # print((wiper_voltage(wiper_pin),))