update example

Author: caternuson

adafruit_mcp230xx.py

@@ -0,0 +1,135 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2017 Tony DiCola for Adafruit Industries
+#                    refactor by Carter Nelson
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+"""
+`digital_inout`
+====================================================
+
+Digital input/output of the MCP230xx.
+
+* Author(s): Tony DiCola
+"""
+
+import digitalio
+
+__version__ = "0.0.0-auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_MCP230xx.git"
+
+# Internal helpers to simplify setting and getting a bit inside an integer.
+def _get_bit(val, bit):
+    return val & (1 << bit) > 0
+
+def _enable_bit(val, bit):
+    return val | (1 << bit)
+
+def _clear_bit(val, bit):
+    return val & ~(1 << bit)
+
+
+class DigitalInOut:
+    """Digital input/output of the MCP230xx.  The interface is exactly the
+    same as the digitalio.DigitalInOut class (however the MCP230xx does not
+    support pull-down resistors and an exception will be thrown
+    attempting to set one).
+    """
+
+    def __init__(self, pin_number, mcp230xx):
+        """Specify the pin number of the MCP230xx (0...7 for MCP23008, or 0...15
+        for MCP23017) and MCP23008 instance.
+        """
+        self._pin = pin_number
+        self._mcp = mcp230xx
+
+    # kwargs in switch functions below are _necessary_ for compatibility
+    # with DigitalInout class (which allows specifying pull, etc. which
+    # is unused by this class).  Do not remove them, instead turn off pylint
+    # in this case.
+    #pylint: disable=unused-argument
+    def switch_to_output(self, value=False, **kwargs):
+        """Switch the pin state to a digital output with the provided starting
+        value (True/False for high or low, default is False/low).
+        """
+        self.direction = digitalio.Direction.OUTPUT
+        self.value = value
+
+    def switch_to_input(self, pull=None, **kwargs):
+        """Switch the pin state to a digital input with the provided starting
+        pull-up resistor state (optional, no pull-up by default).  Note that
+        pull-down resistors are NOT supported!
+        """
+        self.direction = digitalio.Direction.INPUT
+        self.pull = pull
+    #pylint: enable=unused-argument
+
+    @property
+    def value(self):
+        """The value of the pin, either True for high or False for
+        low.  Note you must configure as an output or input appropriately
+        before reading and writing this value.
+        """
+        return _get_bit(self._mcp.gpio, self._pin)
+
+    @value.setter
+    def value(self, val):
+        if val:
+            self._mcp.gpio = _enable_bit(self._mcp.gpio, self._pin)
+        else:
+            self._mcp.gpio = _clear_bit(self._mcp.gpio, self._pin)
+
+    @property
+    def direction(self):
+        """The direction of the pin, either True for an input or
+        False for an output.
+        """
+        if _get_bit(self._mcp.iodir, self._pin):
+            return digitalio.Direction.INPUT
+        return digitalio.Direction.OUTPUT
+
+    @direction.setter
+    def direction(self, val):
+        if val == digitalio.Direction.INPUT:
+            self._mcp.iodir = _enable_bit(self._mcp.iodir, self._pin)
+        elif val == digitalio.Direction.OUTPUT:
+            self._mcp.iodir = _clear_bit(self._mcp.iodir, self._pin)
+        else:
+            raise ValueError('Expected INPUT or OUTPUT direction!')
+
+    @property
+    def pull(self):
+        """Enable or disable internal pull-up resistors for this pin.  A
+        value of digitalio.Pull.UP will enable a pull-up resistor, and None will
+        disable it.  Pull-down resistors are NOT supported!
+        """
+        if _get_bit(self._mcp.gppu, self._pin):
+            return digitalio.Pull.UP
+        return None
+
+    @pull.setter
+    def pull(self, val):
+        if val is None:
+            self._mcp.gppu = _clear_bit(self._mcp.gppu, self._pin)
+        elif val == digitalio.Pull.UP:
+            self._mcp.gppu = _enable_bit(self._mcp.gppu, self._pin)
+        elif val == digitalio.Pull.DOWN:
+            raise ValueError('Pull-down resistors are not supported!')
+        else:
+            raise ValueError('Expected UP, DOWN, or None for pull state!')

adafruit_mcp230xx/__init__.py

@@ -0,0 +1,99 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2017 Tony DiCola for Adafruit Industries
+#                    refactor by Carter Nelson
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+"""
+`mcp23008`
+====================================================
+
+CircuitPython module for the MCP23008 I2C I/O extenders.
+
+* Author(s): Tony DiCola
+"""
+
+from micropython import const
+from adafruit_bus_device import i2c_device
+from .mcp230xx import MCP230XX
+from .digital_inout import DigitalInOut
+
+__version__ = "0.0.0-auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_MCP230xx.git"
+
+_MCP23008_ADDRESS       = const(0x20)
+_MCP23008_IODIR         = const(0x00)
+_MCP23008_GPPU          = const(0x06)
+_MCP23008_GPIO          = const(0x09)
+
+
+class MCP23008(MCP230XX):
+    """Initialize MCP23008 instance on specified I2C bus and optionally
+    at the specified I2C address.
+    """
+
+    def __init__(self, i2c, address=_MCP23008_ADDRESS):
+        self._device = i2c_device.I2CDevice(i2c, address)
+        # Reset device state to all pins as inputs (safest option).
+        with self._device as device:
+            # Write to MCP23008_IODIR register 0xFF followed by 9 zeros
+            # for defaults of other registers.
+            device.write('\x00\xFF\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+    @property
+    def gpio(self):
+        """The raw GPIO output register.  Each bit represents the
+        output value of the associated pin (0 = low, 1 = high), assuming that
+        pin has been configured as an output previously.
+        """
+        return self._read_u8(_MCP23008_GPIO)
+
+    @gpio.setter
+    def gpio(self, val):
+        self._write_u8(_MCP23008_GPIO, val)
+
+    @property
+    def iodir(self):
+        """The raw IODIR direction register.  Each bit represents
+        direction of a pin, either 1 for an input or 0 for an output mode.
+        """
+        return self._read_u8(_MCP23008_IODIR)
+
+    @iodir.setter
+    def iodir(self, val):
+        self._write_u8(_MCP23008_IODIR, val)
+
+    @property
+    def gppu(self):
+        """The raw GPPU pull-up register.  Each bit represents
+        if a pull-up is enabled on the specified pin (1 = pull-up enabled,
+        0 = pull-up disabled).  Note pull-down resistors are NOT supported!
+        """
+        return self._read_u8(_MCP23008_GPPU)
+
+    @gppu.setter
+    def gppu(self, val):
+        self._write_u8(_MCP23008_GPPU, val)
+
+    def get_pin(self, pin):
+        """Convenience function to create an instance of the DigitalInOut class
+        pointing at the specified pin of this MCP23008 device.
+        """
+        assert 0 <= pin <= 7
+        return DigitalInOut(pin, self)