Merge pull request #19 from caternuson/iss17_update

Interface change for #17

Author: kattni

README.rst

@@ -62,31 +62,29 @@ Single Ended
 
 .. code-block:: python
 
-  import board
-  import busio
-  from adafruit_ads1x15.single_ended import ADS1015
+    import time
+    import board
+    import busio
+    import adafruit_ads1x15.ads1015 as ADS
+    from adafruit_ads1x15.analog_in import AnalogIn
 
-  i2c = busio.I2C(board.SCL, board.SDA)
-  adc = ADS1015(i2c)
-  while True:
-      # channel 0
-      print(adc[0].value, adc[0].volts)
+    # Create the I2C bus
+    i2c = busio.I2C(board.SCL, board.SDA)
 
-Differential
-------------
+    # Create the ADC object using the I2C bus
+    ads = ADS.ADS1015(i2c)
 
-.. code-block:: python
+    # Create single-ended input on channel 0
+    chan = AnalogIn(ads, ADS.P0)
 
-  import board
-  import busio
-  from adafruit_ads1x15.differential import ADS1015
+    # Create differential input between channel 0 and 1
+    #chan = AnalogIn(ads, ADS.P0, ADS.P1)
 
-  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)
+    print("{:>5}\t{:>5}".format('raw', 'v'))
 
+    while True:
+        print("{:>5}\t{:>5.3f}".format(chan.value, chan.voltage))
+        time.sleep(0.5)
 
 Contributing
 ============

adafruit_ads1x15/adafruit_ads1x15.py

@@ -0,0 +1,76 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2018 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.
+"""
+`ads1015`
+====================================================
+
+CircuitPython driver for ADS1015 ADCs.
+
+* Author(s): Carter Nelson
+"""
+import struct
+from .ads1x15 import ADS1x15
+
+# Data sample rates
+_ADS1015_CONFIG_DR = {
+    128:   0x0000,
+    250:   0x0020,
+    490:   0x0040,
+    920:   0x0060,
+    1600:  0x0080,
+    2400:  0x00A0,
+    3300:  0x00C0
+}
+
+# Pins
+P0 = 0
+P1 = 1
+P2 = 2
+P3 = 3
+
+class ADS1015(ADS1x15):
+    """Class for the ADS1015 12 bit ADC."""
+
+    @property
+    def bits(self):
+        """The ADC bit resolution."""
+        return 12
+
+    @property
+    def rates(self):
+        """Possible data rate settings."""
+        r = list(_ADS1015_CONFIG_DR.keys())
+        r.sort()
+        return r
+
+    @property
+    def rate_config(self):
+        """Rate configuration masks."""
+        return _ADS1015_CONFIG_DR
+
+    def _data_rate_default(self):
+        return 1600
+
+    def _conversion_value(self, raw_adc):
+        raw_adc = raw_adc.to_bytes(2, "big")
+        value = struct.unpack(">h", raw_adc)[0]
+        return value >> 4