Merge pull request #48 from pimoroni/ads1015-library

Migrate to ADS1015 library for #11

library/automationhat/__init__.py

@@ -1,14 +1,22 @@
 import atexit
 import time
 import warnings
-from sys import version_info
 
 try:
     import RPi.GPIO as GPIO
 except ImportError:
-    raise ImportError("This library requires the RPi.GPIO module\nInstall with: sudo pip install RPi.GPIO")
+    raise ImportError("This library requires the RPi.GPIO module\nInstall with: sudo python3 -m pip install RPi.GPIO")
+
+try:
+    import smbus
+except ImportError:
+    raise ImportError("This library requires python3-smbus\nInstall with: sudo apt install python3-smbus")
+
+try:
+    import ads1015
+except ImportError:
+    raise ImportError("This library requires ads1015\nInstall with: sudo python3 -m pip install ads1015")
 
-from .ads1015 import ads1015
 from .pins import ObjectCollection, AsyncWorker, StoppableThread
 
 __version__ = '0.3.0'
@@ -38,6 +46,7 @@
 _lights_need_updating = False
 _is_setup = False
 _t_update_lights = None
+_ads1015 = None
 
 
 class SNLight(object):
@@ -121,7 +130,7 @@ def read(self):
 
     def _update(self):
         self.setup()
-        self.value = _ads1015.read(self.channel)
+        self.value = _ads1015.get_voltage("in{}/gnd".format(self.channel)) / 3.3
 
         if self._en_auto_lights:
             adc = self.value
@@ -343,23 +352,23 @@ def setup():
     GPIO.setmode(GPIO.BCM)
     GPIO.setwarnings(False)
 
+    _ads1015 = ads1015.ADS1015()
     try:
-        import smbus
-    except ImportError:
-        if version_info[0] < 3:
-            raise ImportError("This library requires python-smbus\nInstall with: sudo apt install python-smbus")
-        elif version_info[0] == 3:
-            raise ImportError("This library requires python3-smbus\nInstall with: sudo apt install python3-smbus")
+        chip_type = _ads1015.detect_chip_type()
+    except IOError:
+        raise RuntimeError("No ADC detected, check your connections")
 
-    _ads1015 = ads1015(smbus.SMBus(1))
+    if chip_type == 'ADS1015':
+        _ads1015.set_sample_rate(1600)
+    else:
+        _ads1015.set_sample_rate(860)
 
-    if _ads1015.available() is False:
-        raise RuntimeError("No ADC detected, check your connections")
+    _ads1015.set_programmable_gain(4.096)
 
     try:
         import sn3218
     except ImportError:
-        raise ImportError("This library requires sn3218\nInstall with: sudo pip install sn3218")
+        raise ImportError("This library requires sn3218\nInstall with: sudo python3 -m pip install sn3218")
     except IOError:
         pass
 

library/setup.cfg

@@ -36,6 +36,7 @@ install_requires =
     RPi.GPIO
     sn3218
     ST7735
+    ads1015>=0.0.8
 
 [flake8]
 exclude =
@@ -57,4 +58,4 @@ configtxt =
 commands =
 	printf "Setting up i2c and SPI..\n"
 	raspi-config nonint do_spi 0
-	raspi-config nonint do_i2c 0
+	raspi-config nonint do_i2c 0

library/tests/conftest.py

@@ -3,49 +3,30 @@
 import pytest
 
 
-class MockSMBus():
-    def __init__(self, bus):
-        self.regs = {
-            0x48: [0 for _ in range(255)],  # ads1015,
-            0x54: [0 for _ in range(255)]   # sn3218
-        }
-        self.regs[0x48][0] = (1 << 11) - 1  # 12-bit ADC, 12th bit is sign
-
-        # Set the uppermost bit of the ADS1015 CONFIG register
-        # to indicate an "inactive/start" status
-        self.regs[0x48][1] = 0b10000000
-
-    def read_i2c_block_data(self, address, register, length=2):
-        if (address, register) == (0x48, 0):
-            value = self.regs[address][register:register+(length // 2)]
-            return [(value[0] >> 4) & 0xff, (value[0] & 0x0f) << 4]
-        return self.regs[address][register:register+length]
-
-    def write_i2c_block_data(self, address, register, data):
-        if (address, register) == (0x48, 1):
-            return 0
-        self.regs[address][register:register+len(data)] = data
+@pytest.fixture(scope='function')
+def automationhat():
+    import automationhat
+    yield automationhat
+    del sys.modules['automationhat']
 
 
 @pytest.fixture(scope='function')
-def smbus_notimeout():
-    sys.modules['smbus'] = mock.Mock()
-    sys.modules['smbus'].SMBus = MockSMBus
-    yield
-    del sys.modules['smbus']
+def ads1015():
+    sys.modules['ads1015'] = mock.MagicMock()
+    yield sys.modules['ads1015']
+    del sys.modules['ads1015']
 
 
 @pytest.fixture(scope='function')
-def smbus_timeout():
-    sys.modules['smbus'] = mock.Mock()
-    sys.modules['smbus'].SMBus = MockSMBus
-    yield
-    del sys.modules['smbus']
+def sn3218():
+    sys.modules['sn3218'] = mock.MagicMock()
+    yield sys.modules['sn3218']
+    del sys.modules['sn3218']
 
 
 @pytest.fixture(scope='function')
-def mocksmbus():
-    sys.modules['smbus'] = mock.Mock()
+def smbus():
+    sys.modules['smbus'] = mock.MagicMock()
     yield sys.modules['smbus']
     del sys.modules['smbus']
 

library/tests/test_setup.py

@@ -2,20 +2,22 @@
 import sys
 
 
-def test_setup(gpio, smbus_notimeout):
-    import automationhat
+def test_setup(gpio, smbus, sn3218, ads1015, automationhat):
     automationhat.setup()
 
 
-def test_analog(smbus_notimeout):
-    import automationhat
+def test_analog(gpio, smbus, sn3218, ads1015, automationhat):
+    automationhat.setup()
+
+    ads1015.ADS1015().get_voltage.return_value = 3.3
+
     # VCC = 3.3, GAIN = 4.096, FS = 2.027, Max Voltage = 25.85
     # output ~= ((1 << 11) - 1) / 2047.0 * 2096.0 / 3300.0 * 25.85
-    assert round(automationhat.analog.one.read(), 1) == 32.1
-    assert round(automationhat.analog.two.read(), 1) == 32.1
-    assert round(automationhat.analog.three.read(), 1) == 32.1
+    assert round(automationhat.analog.one.read(), 2) == 25.85
+    assert round(automationhat.analog.two.read(), 2) == 25.85
+    assert round(automationhat.analog.three.read(), 2) == 25.85
 
     values = automationhat.analog.read()
     for k, v in values.items():
-        values[k] = round(v, 1)
-    assert values == {'one': 32.1, 'two': 32.1, 'three': 32.1, 'four': 4.1}
+        values[k] = round(v, 2)
+    assert values == {'one': 25.85, 'two': 25.85, 'three': 25.85, 'four': 3.3}