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 adafruit_blinka.agnostic import board_id, detector
  11
  12 # pylint: disable=ungrouped-imports,wrong-import-position
  13
  14 if detector.chip.BCM2XXX:
  15     from adafruit_blinka.microcontroller.bcm283x.pin import Pin
  16 elif detector.chip.AM33XX:
  17     from adafruit_blinka.microcontroller.am335x.pin import Pin
  18 elif detector.chip.SUN8I:
  19     from adafruit_blinka.microcontroller.allwinner_h3.pin import Pin
  20 elif detector.chip.STM32:
  21     from machine import Pin
  22 from adafruit_blinka import Enum, ContextManaged
  23
  24 class DriveMode(Enum):
  25     PUSH_PULL = None
  26     OPEN_DRAIN = None
  27
  28
  29 DriveMode.PUSH_PULL = DriveMode()
  30 DriveMode.OPEN_DRAIN = DriveMode()
  31
  32
  33 class Direction(Enum):
  34     INPUT = None
  35     OUTPUT = None
  36
  37
  38 Direction.INPUT = Direction()
  39 Direction.OUTPUT = Direction()
  40
  41
  42 class Pull(Enum):
  43     UP = None
  44     DOWN = None
  45     #NONE=None
  46
  47
  48 Pull.UP = Pull()
  49 Pull.DOWN = Pull()
  50
  51 #Pull.NONE = Pull()
  52
  53
  54 class DigitalInOut(ContextManaged):
  55     _pin = None
  56
  57     def __init__(self, pin):
  58         self._pin = Pin(pin.id)
  59         self.direction = Direction.INPUT
  60
  61     def switch_to_output(self, value=False, drive_mode=DriveMode.PUSH_PULL):
  62         self.direction = Direction.OUTPUT
  63         self.value = value
  64         self.drive_mode = drive_mode
  65
  66     def switch_to_input(self, pull=None):
  67         self.direction = Direction.INPUT
  68         self.pull = pull
  69
  70     def deinit(self):
  71         del self._pin
  72
  73     @property
  74     def direction(self):
  75         return self.__direction
  76
  77     @direction.setter
  78     def direction(self, dir):
  79         self.__direction = dir
  80         if dir is Direction.OUTPUT:
  81             self._pin.init(mode=Pin.OUT)
  82             self.value = False
  83             self.drive_mode = DriveMode.PUSH_PULL
  84         elif dir is Direction.INPUT:
  85             self._pin.init(mode=Pin.IN)
  86             self.pull = None
  87         else:
  88             raise AttributeError("Not a Direction")
  89
  90     @property
  91     def value(self):
  92         return self._pin.value() is 1
  93
  94     @value.setter
  95     def value(self, val):
  96         if self.direction is Direction.OUTPUT:
  97             self._pin.value(1 if val else 0)
  98         else:
  99             raise AttributeError("Not an output")
 100
 101     @property
 102     def pull(self):
 103         if self.direction is Direction.INPUT:
 104             return self.__pull
 105         else:
 106             raise AttributeError("Not an input")
 107
 108     @pull.setter
 109     def pull(self, pul):
 110         if self.direction is Direction.INPUT:
 111             self.__pull = pul
 112             if pul is Pull.UP:
 113                 self._pin.init(mode=Pin.IN, pull=Pin.PULL_UP)
 114             elif pul is Pull.DOWN:
 115                 if hasattr(Pin, "PULL_DOWN"):
 116                     self._pin.init(mode=Pin.IN, pull=Pin.PULL_DOWN)
 117                 else:
 118                     raise NotImplementedError("{} unsupported on {}".format(
 119                         Pull.DOWN, board_id))
 120             elif pul is None:
 121                 self._pin.init(mode=Pin.IN, pull=None)
 122             else:
 123                 raise AttributeError("Not a Pull")
 124         else:
 125             raise AttributeError("Not an input")
 126
 127     @property
 128     def drive_mode(self):
 129         if self.direction is Direction.OUTPUT:
 130             return self.__drive_mode  #
 131         else:
 132             raise AttributeError("Not an output")
 133
 134     @drive_mode.setter
 135     def drive_mode(self, mod):
 136         self.__drive_mode = mod
 137         if mod is DriveMode.OPEN_DRAIN:
 138             self._pin.init(mode=Pin.OPEN_DRAIN)
 139         elif mod is DriveMode.PUSH_PULL:
 140             self._pin.init(mode=Pin.OUT)