Adds in code from working repo

CODE_OF_CONDUCT.md

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+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, gender identity and expression, level of experience,
+nationality, personal appearance, race, religion, or sexual identity and
+orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at [email protected]. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at [http://contributor-covenant.org/version/1/4][version]
+
+[homepage]: http://contributor-covenant.org
+[version]: http://contributor-covenant.org/version/1/4/

LICENSE

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+The MIT License (MIT)
+
+Copyright (c) 2017 Carter Nelson for Adafruit Industries
+
+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.

README.rst

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+
+Introduction
+============
+
+.. image:: https://readthedocs.org/projects/adafruit-circuitpython-CircuitPython_ADS1x15/badge/?version=latest
+    :target: https://circuitpython.readthedocs.io/projects/CircuitPython_ADS1x15/en/latest/
+    :alt: Documentation Status
+
+.. image :: https://badges.gitter.im/adafruit/circuitpython.svg
+    :target: https://gitter.im/adafruit/circuitpython?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge
+    :alt: Gitter
+
+Support for the ADS1x15 series of analog-to-digital converters. Available in 12-bit (ADS1015)
+and 16-bit (ADS1115) versions.
+
+Dependencies
+=============
+This driver depends on:
+
+* `Adafruit CircuitPython <https://github.com/adafruit/circuitpython>`_
+* `Bus Device <https://github.com/adafruit/Adafruit_CircuitPython_BusDevice>`_
+
+Please ensure all dependencies are available on the CircuitPython filesystem.
+This is easily achieved by downloading
+`the Adafruit library and driver bundle <https://github.com/adafruit/Adafruit_CircuitPython_Bundle>`_.
+
+Usage Example
+=============
+
+Single Ended
+------------
+
+.. code-block:: python
+
+  import board
+  import busio
+  from adafruit_ads1x15.single_ended import ADS1015
+
+  i2c = busio.I2C(board.SCL, board.SDA)
+  adc = ADS1015(i2c)
+  while True:
+      # channel 0
+      print(adc[0].value, adc[0].volts)
+
+Differential
+------------
+
+.. code-block:: python
+
+  import board
+  import busio
+  from adafruit_ads1x15.differential import ADS1015
+
+  i2c = busio.I2C(board.SCL, board.SDA)
+  adc = ADS1015(i2c)
+  while True:
+      # channel 0 - channel 1
+      print(adc[(0,1)].value, adc[(0,1)].volts)
+
+
+Contributing
+============
+
+Contributions are welcome! Please read our `Code of Conduct
+<https://github.com/adafruit/Adafruit_CircuitPython_CircuitPython_ADS1x15/blob/master/CODE_OF_CONDUCT.md>`_
+before contributing to help this project stay welcoming.
+
+API Reference
+=============
+
+.. toctree::
+   :maxdepth: 2
+
+   api

adafruit_ads1x15/adafruit_ads1x15.py

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+# The MIT License (MIT)
+#
+# Copyright (c) 2017 Carter Nelson for Adafruit Industries
+#
+# 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.
+"""
+`adafruit__ads1x15`
+====================================================
+
+CircuitPython driver for ADS1015/1115 ADCs.
+
+* Author(s): Carter Nelson
+"""
+import time
+from micropython import const
+from adafruit_bus_device.i2c_device import I2CDevice
+
+# Register and other configuration values:
+ADS1x15_DEFAULT_ADDRESS        = const(0x48)
+ADS1x15_POINTER_CONVERSION     = const(0x00)
+ADS1x15_POINTER_CONFIG         = const(0x01)
+ADS1x15_POINTER_LOW_THRESHOLD  = const(0x02)
+ADS1x15_POINTER_HIGH_THRESHOLD = const(0x03)
+ADS1x15_CONFIG_OS_SINGLE       = const(0x8000)
+ADS1x15_CONFIG_MUX_OFFSET      = const(12)
+# Maping of gain values to config register values.
+ADS1x15_CONFIG_GAIN = {
+    2/3: 0x0000,
+    1:   0x0200,
+    2:   0x0400,
+    4:   0x0600,
+    8:   0x0800,
+    16:  0x0A00
+}
+ADS1x15_PGA_RANGE = {
+    2/3: 6.144,
+    1:   4.096,
+    2:   2.048,
+    4:   1.024,
+    8:   0.512,
+    16:  0.256
+}
+ADS1x15_CONFIG_MODE_CONTINUOUS  = const(0x0000)
+ADS1x15_CONFIG_MODE_SINGLE      = const(0x0100)
+# Mapping of data/sample rate to config register values for ADS1015 (faster).
+ADS1015_CONFIG_DR = {
+    128:   0x0000,
+    250:   0x0020,
+    490:   0x0040,
+    920:   0x0060,
+    1600:  0x0080,
+    2400:  0x00A0,
+    3300:  0x00C0
+}
+# Mapping of data/sample rate to config register values for ADS1115 (slower).
+ADS1115_CONFIG_DR = {
+    8:    0x0000,
+    16:   0x0020,
+    32:   0x0040,
+    64:   0x0060,
+    128:  0x0080,
+    250:  0x00A0,
+    475:  0x00C0,
+    860:  0x00E0
+}
+ADS1x15_CONFIG_COMP_WINDOW      = const(0x0010)
+ADS1x15_CONFIG_COMP_ACTIVE_HIGH = const(0x0008)
+ADS1x15_CONFIG_COMP_LATCHING    = const(0x0004)
+ADS1x15_CONFIG_COMP_QUE = {
+    1: 0x0000,
+    2: 0x0001,
+    4: 0x0002
+}
+ADS1x15_CONFIG_COMP_QUE_DISABLE = const(0x0003)
+ADS1x15_DIFF_CHANNELS = {
+    (0,1): 0,
+    (0,3): 1,
+    (1,3): 2,
+    (2,3): 3
+}
+
+class ADC_Channel(object):
+    """Provides per channel access to ADC readings."""
+
+    def __init__(self, adc, channel):
+        self._adc = adc
+        self._channel = channel
+
+    @property
+    def value(self, ):
+        """ADC reading in raw counts."""
+        return self._adc._read_channel(self._channel)
+
+    @property
+    def volts(self, ):
+        """ADC reading in volts."""
+        return self._adc._read_channel_volts(self._channel)
+
+
+class ADS1x15(object):
+    """Base functionality for ADS1x15 analog to digital converters."""
+
+    def __init__(self, i2c, address=ADS1x15_DEFAULT_ADDRESS, **kwargs):
+        self.buf = bytearray(3)
+        self.i2c_device = I2CDevice(i2c, address)
+        self.bits = None
+        self._channels = [ADC_Channel(self, 0),
+                          ADC_Channel(self, 1),
+                          ADC_Channel(self, 2),
+                          ADC_Channel(self, 3)]
+
+    def _data_rate_default(self):
+        """Retrieve the default data rate for this ADC (in samples per second).
+        Should be implemented by subclasses.
+        """
+        raise NotImplementedError('Subclasses must implement _data_rate_default!')
+
+    def _data_rate_config(self, data_rate):
+        """Subclasses should override this function and return a 16-bit value
+        that can be OR'ed with the config register to set the specified
+        data rate.  If a value of None is specified then a default data_rate
+        setting should be returned.  If an invalid or unsupported data_rate is
+        provided then an exception should be thrown.
+        """
+        raise NotImplementedError('Subclass must implement _data_rate_config function!')
+
+    def _conversion_value(self, low, high):
+        """Subclasses should override this function that takes the low and high
+        byte of a conversion result and returns a signed integer value.
+        """
+        raise NotImplementedError('Subclass must implement _conversion_value function!')
+
+    def _read_channel(self, channel):
+        """Subclasses should override this function to return a value for the
+        requested channels as a signed integer value.
+        """
+        raise NotImplementedError('Subclass must implement _read_channel function!')
+
+    def _read_channel_volts(self, channel):
+        """Subclasses should override this function to return a value for the
+        requested channels as a float value.
+        """
+        raise NotImplementedError('Subclass must implement _read_channel_volts function!')
+
+    def _read(self, mux, gain, data_rate, mode):
+        """Perform an ADC read with the provided mux, gain, data_rate, and mode
+        values.  Returns the signed integer result of the read.
+        """
+        config = ADS1x15_CONFIG_OS_SINGLE  # Go out of power-down mode for conversion.
+        # Specify mux value.
+        config |= (mux & 0x07) << ADS1x15_CONFIG_MUX_OFFSET
+        # Validate the passed in gain and then set it in the config.
+        if gain not in ADS1x15_CONFIG_GAIN:
+            raise ValueError('Gain must be one of: 2/3, 1, 2, 4, 8, 16')
+        config |= ADS1x15_CONFIG_GAIN[gain]
+        # Set the mode (continuous or single shot).
+        config |= mode
+        # Get the default data rate if none is specified (default differs between
+        # ADS1015 and ADS1115).
+        if data_rate is None:
+            data_rate = self._data_rate_default()
+        # Set the data rate (this is controlled by the subclass as it differs
+        # between ADS1015 and ADS1115).
+        config |= self._data_rate_config(data_rate)
+        config |= ADS1x15_CONFIG_COMP_QUE_DISABLE  # Disble comparator mode.
+        # Send the config value to start the ADC conversion.
+        # Explicitly break the 16-bit value down to a big endian pair of bytes.
+        self.buf[0] = ADS1x15_POINTER_CONFIG
+        self.buf[1] = (config >> 8) & 0xFF
+        self.buf[2] = config & 0xFF
+        with self.i2c_device as i2c:
+            i2c.write(self.buf)
+            # Wait for the ADC sample to finish based on the sample rate plus a
+            # small offset to be sure (0.1 millisecond).
+            time.sleep(1.0/data_rate+0.0001)
+            # Retrieve the result.
+            self.buf[0] = ADS1x15_POINTER_CONVERSION
+            i2c.write(self.buf, end=1, stop=False)
+            i2c.read_into(self.buf, start=1)
+        return self._conversion_value(self.buf[2], self.buf[1])
+
+    def stop_adc(self):
+        """Stop all continuous ADC conversions (either normal or difference mode).
+        """
+        # Set the config register to its default value of 0x8583 to stop
+        # continuous conversions.
+        self.buf[0] = ADS1x15_POINTER_CONFIG
+        self.buf[1] = 0x85
+        self.buf[2] = 0x83
+        with self.i2c_device as i2c:
+            i2c.write(self.buf)
+
+    def get_last_result(self):
+        """Read the last conversion result when in continuous conversion mode.
+        Will return a signed integer value.
+        """
+        # Retrieve the conversion register value, convert to a signed int, and
+        # return it.
+        self.buf[0] = ADS1x15_POINTER_CONVERSION
+        with self.i2c_device as i2c:
+            i2c.write(self.buf, end=1, stop=False)
+            i2c.read_into(self.buf, start=1)
+        return self._conversion_value(self.buf[2], self.buf[1])