1  # SPDX-FileCopyrightText: 2021 foamyguy for Adafruit Industries
  2  #
  3  # SPDX-License-Identifier: MIT
  4  
  5  """
  6  Rotary Trinkey gadget that forces you to crank the handle in order
  7  to keep the brightness up on your phone or tablet.
  8  """
  9  
 10  import time
 11  import math
 12  import board
 13  import digitalio
 14  import rotaryio
 15  import usb_hid
 16  from adafruit_hid.consumer_control import ConsumerControl
 17  from adafruit_hid.consumer_control_code import ConsumerControlCode
 18  
 19  # how frequently we check the encoder value and apply brightness changes
 20  ACTION_INTERVAL = 3  # seconds
 21  
 22  # if encoder value increases at least this much
 23  # then brightness stays the same
 24  # if encoder value increases less than this
 25  # then brightness goes down
 26  STAY_EVEN_CHANGE_THRESHOLD = 60
 27  
 28  # if encoder value increases at least this much
 29  # then brightness goes up
 30  INCREASE_CHANGE_THRESHOLD = 95
 31  
 32  # timestamp of last time an action occurred
 33  LAST_ACTION_TIME = 0
 34  
 35  # encoder value variable
 36  CUR_VALUE = 0
 37  
 38  # pause state
 39  PAUSED = False
 40  
 41  cc = ConsumerControl(usb_hid.devices)
 42  
 43  encoder = rotaryio.IncrementalEncoder(board.ROTA, board.ROTB)
 44  switch = digitalio.DigitalInOut(board.SWITCH)
 45  switch.switch_to_input(pull=digitalio.Pull.DOWN)
 46  
 47  switch_state = None
 48  
 49  # previous encoder position variable
 50  last_position = encoder.position
 51  
 52  # previous switch variable
 53  prev_switch_value = False
 54  
 55  while True:
 56      now = time.monotonic()
 57  
 58      if switch.value and not prev_switch_value:
 59          print("toggling pause")
 60          PAUSED = not PAUSED
 61  
 62          if not PAUSED:
 63              LAST_ACTION_TIME = now
 64  
 65      prev_switch_value = switch.value
 66  
 67      # read current encoder value
 68      current_position = encoder.position
 69      position_change = int(current_position - last_position)
 70  
 71      # positive change
 72      if position_change > 0:
 73          for _ in range(position_change):
 74              CUR_VALUE += position_change
 75  
 76      # negative change
 77      elif position_change < 0:
 78          for _ in range(-position_change):
 79              # use absolute value to convert to positive
 80              CUR_VALUE += int(math.fabs(position_change))
 81  
 82      last_position = current_position
 83  
 84      if not PAUSED:
 85          # is it time for an action?
 86          if now > LAST_ACTION_TIME + ACTION_INTERVAL:
 87              print(CUR_VALUE)
 88  
 89              # update previous time variable
 90              LAST_ACTION_TIME = now
 91  
 92              # less than stay even threshold
 93              if CUR_VALUE < STAY_EVEN_CHANGE_THRESHOLD:
 94                  cc.send(ConsumerControlCode.BRIGHTNESS_DECREMENT)
 95                  print("brightness down")
 96  
 97              # more than stay even threshold
 98              elif CUR_VALUE < INCREASE_CHANGE_THRESHOLD:
 99                  print("stay even")
100  
101              # more than increase threshold
102              else:
103                  cc.send(ConsumerControlCode.BRIGHTNESS_INCREMENT)
104                  print("brightness up")
105  
106              # reset encoder value
107              CUR_VALUE = 0
108  
109