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