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.SAMA5:
  21     from adafruit_blinka.microcontroller.sama5.pin import Pin
  22 elif detector.chip.T210:
  23     from adafruit_blinka.microcontroller.tegra.t210.pin import Pin
  24 elif detector.chip.T186:
  25     from adafruit_blinka.microcontroller.tegra.t186.pin import Pin
  26 elif detector.chip.T194:
  27     from adafruit_blinka.microcontroller.tegra.t194.pin import Pin
  28 elif detector.chip.STM32:
  29     from machine import Pin
  30 from adafruit_blinka import Enum, ContextManaged
  31
  32 class DriveMode(Enum):
  33     PUSH_PULL = None
  34     OPEN_DRAIN = None
  35
  36
  37 DriveMode.PUSH_PULL = DriveMode()
  38 DriveMode.OPEN_DRAIN = DriveMode()
  39
  40
  41 class Direction(Enum):
  42     INPUT = None
  43     OUTPUT = None
  44
  45
  46 Direction.INPUT = Direction()
  47 Direction.OUTPUT = Direction()
  48
  49
  50 class Pull(Enum):
  51     UP = None
  52     DOWN = None
  53     #NONE=None
  54
  55
  56 Pull.UP = Pull()
  57 Pull.DOWN = Pull()
  58
  59 #Pull.NONE = Pull()
  60
  61
  62 class DigitalInOut(ContextManaged):
  63     _pin = None
  64
  65     def __init__(self, pin):
  66         self._pin = Pin(pin.id)
  67         self.direction = Direction.INPUT
  68
  69     def switch_to_output(self, value=False, drive_mode=DriveMode.PUSH_PULL):
  70         self.direction = Direction.OUTPUT
  71         self.value = value
  72         self.drive_mode = drive_mode
  73
  74     def switch_to_input(self, pull=None):
  75         self.direction = Direction.INPUT
  76         self.pull = pull
  77
  78     def deinit(self):
  79         del self._pin
  80
  81     @property
  82     def direction(self):
  83         return self.__direction
  84
  85     @direction.setter
  86     def direction(self, dir):
  87         self.__direction = dir
  88         if dir is Direction.OUTPUT:
  89             self._pin.init(mode=Pin.OUT)
  90             self.value = False
  91             self.drive_mode = DriveMode.PUSH_PULL
  92         elif dir is Direction.INPUT:
  93             self._pin.init(mode=Pin.IN)
  94             self.pull = None
  95         else:
  96             raise AttributeError("Not a Direction")
  97
  98     @property
  99     def value(self):
 100         return self._pin.value() is 1
 101
 102     @value.setter
 103     def value(self, val):
 104         if self.direction is Direction.OUTPUT:
 105             self._pin.value(1 if val else 0)
 106         else:
 107             raise AttributeError("Not an output")
 108
 109     @property
 110     def pull(self):
 111         if self.direction is Direction.INPUT:
 112             return self.__pull
 113         else:
 114             raise AttributeError("Not an input")
 115
 116     @pull.setter
 117     def pull(self, pul):
 118         if self.direction is Direction.INPUT:
 119             self.__pull = pul
 120             if pul is Pull.UP:
 121                 self._pin.init(mode=Pin.IN, pull=Pin.PULL_UP)
 122             elif pul is Pull.DOWN:
 123                 if hasattr(Pin, "PULL_DOWN"):
 124                     self._pin.init(mode=Pin.IN, pull=Pin.PULL_DOWN)
 125                 else:
 126                     raise NotImplementedError("{} unsupported on {}".format(
 127                         Pull.DOWN, board_id))
 128             elif pul is None:
 129                 self._pin.init(mode=Pin.IN, pull=None)
 130             else:
 131                 raise AttributeError("Not a Pull")
 132         else:
 133             raise AttributeError("Not an input")
 134
 135     @property
 136     def drive_mode(self):
 137         if self.direction is Direction.OUTPUT:
 138             return self.__drive_mode  #
 139         else:
 140             raise AttributeError("Not an output")
 141
 142     @drive_mode.setter
 143     def drive_mode(self, mod):
 144         self.__drive_mode = mod
 145         if mod is DriveMode.OPEN_DRAIN:
 146             self._pin.init(mode=Pin.OPEN_DRAIN)
 147         elif mod is DriveMode.PUSH_PULL:
 148             self._pin.init(mode=Pin.OUT)