src/digitalio.py

   1 """
   2 `digitalio` - Digital input and output control
   3 =================================================
   4
   5 See `CircuitPython:digitalio` in CircuitPython for more details.
   6
   7 * Author(s): cefn
   8 """
   9
  10 from machine import Pin
  11 from adafruit_blinka.agnostic import board as boardId
  12 from adafruit_blinka import Enum, ContextManaged
  13
  14 class DriveMode(Enum):
  15     PUSH_PULL = None
  16     OPEN_DRAIN = None
  17
  18
  19 DriveMode.PUSH_PULL = DriveMode()
  20 DriveMode.OPEN_DRAIN = DriveMode()
  21
  22
  23 class Direction(Enum):
  24     INPUT = None
  25     OUTPUT = None
  26
  27
  28 Direction.INPUT = Direction()
  29 Direction.OUTPUT = Direction()
  30
  31
  32 class Pull(Enum):
  33     UP = None
  34     DOWN = None
  35     #NONE=None
  36
  37
  38 Pull.UP = Pull()
  39 Pull.DOWN = Pull()
  40
  41 #Pull.NONE = Pull()
  42
  43
  44 class DigitalInOut(ContextManaged):
  45     _pin = None
  46
  47     def __init__(self, pin):
  48         self._pin = Pin(pin.id)
  49         self.direction = Direction.INPUT
  50
  51     def switch_to_output(self, value=False, drive_mode=DriveMode.PUSH_PULL):
  52         self.direction = Direction.OUTPUT
  53         self.value = value
  54         self.drive_mode = drive_mode
  55
  56     def switch_to_input(self, pull=None):
  57         self.direction = Direction.INPUT
  58         self.pull = pull
  59
  60     def deinit(self):
  61         del self._pin
  62
  63     @property
  64     def direction(self):
  65         return self.__direction
  66
  67     @direction.setter
  68     def direction(self, dir):
  69         self.__direction = dir
  70         if dir is Direction.OUTPUT:
  71             self._pin.init(mode=Pin.OUT)
  72             self.value = False
  73             self.drive_mode = DriveMode.PUSH_PULL
  74         elif dir is Direction.INPUT:
  75             self._pin.init(mode=Pin.IN)
  76             self.pull = None
  77         else:
  78             raise AttributeError("Not a Direction")
  79
  80     @property
  81     def value(self):
  82         return self._pin.value() is 1
  83
  84     @value.setter
  85     def value(self, val):
  86         if self.direction is Direction.OUTPUT:
  87             self._pin.value(1 if val else 0)
  88         else:
  89             raise AttributeError("Not an output")
  90
  91     @property
  92     def pull(self):
  93         if self.direction is Direction.INPUT:
  94             return self.__pull
  95         else:
  96             raise AttributeError("Not an input")
  97
  98     @pull.setter
  99     def pull(self, pul):
 100         if self.direction is Direction.INPUT:
 101             self.__pull = pul
 102             if pul is Pull.UP:
 103                 self._pin.init(mode=Pin.IN, pull=Pin.PULL_UP)
 104             elif pul is Pull.DOWN:
 105                 if hasattr(Pin, "PULL_DOWN"):
 106                     self._pin.init(mode=Pin.IN, pull=Pin.PULL_DOWN)
 107                 else:
 108                     raise NotImplementedError("{} unsupported on {}".format(
 109                         Pull.DOWN, boardId))
 110             elif pul is None:
 111                 self._pin.init(mode=Pin.IN, pull=None)
 112             else:
 113                 raise AttributeError("Not a Pull")
 114         else:
 115             raise AttributeError("Not an input")
 116
 117     @property
 118     def drive_mode(self):
 119         if self.direction is Direction.OUTPUT:
 120             return self.__drive_mode  #
 121         else:
 122             raise AttributeError("Not an output")
 123
 124     @drive_mode.setter
 125     def drive_mode(self, mod):
 126         self.__drive_mode = mod
 127         if mod is DriveMode.OPEN_DRAIN:
 128             self._pin.init(mode=Pin.OPEN_DRAIN)
 129         elif mod is DriveMode.PUSH_PULL:
 130             self._pin.init(mode=Pin.OUT)