Merge pull request #15 from jposada202020/light_class

memory_reduction

Author: FoamyGuy

README.rst

@@ -13,6 +13,10 @@ Introduction
     :target: https://github.com/adafruit/Adafruit_CircuitPython_DPS310/actions
     :alt: Build Status
 
+.. image:: https://img.shields.io/badge/code%20style-black-000000.svg
+    :target: https://github.com/psf/black
+    :alt: Code Style: Black
+
 Library for the DPS310 Precision Barometric Pressure Sensor
 
 
@@ -53,41 +57,56 @@ To install in a virtual environment in your current project:
     source .env/bin/activate
     pip3 install adafruit-circuitpython-dps310
 
+
+Installing to a connected CircuitPython Device
+==============================================
+Some devices, eg. the QT-PY, are very limited in memory. The DPS310 library contains
+two variants - basic and advanced - which give different levels of functionality.
+
+Installing the DPS310 library could have the following outcomes:
+
+    * It installs successfully and your code runs successfully. Woo-hoo! Continue with
+      your amazing project.
+    * It installs successfully and your code fails to run with a memory allocation
+      error. Try one of the following:
+
+        * If your ``code.py`` is large, especially if it has lots of comments, you
+          can shrink it into a ``.mpy`` file instead. See the Adafruit
+          `Learn Guide <https://learn.adafruit.com/Memory-saving-tips-for-CircuitPython/non-volatile-not-enough-disk-space>`_
+          on shrinking your code.
+        * Only use the basic DPS310 implementation, and remove the following file:
+          ``<CIRCUITPY>/lib/adafruit_dps310/advanced.mpy`` where <CIRCUITPY> is the
+          mounted location of your device. Make sure that your code only uses the basic
+          implementation.
+
+
 Usage Example
 =============
 
 .. code-block:: python3
 
     import time
     import board
-    import adafruit_dps310
+    from adafruit_dps310.basic import DPS310
 
     i2c = board.I2C()   # uses board.SCL and board.SDA
 
-    dps310 = adafruit_dps310.DPS310(i2c)
+    dps310 = DPS310(i2c)
 
     while True:
         print("Temperature = %.2f *C"%dps310.temperature)
         print("Pressure = %.2f hPa"%dps310.pressure)
         print("")
         time.sleep(1.0)
 
-Caveat: by default the library initializes the IC with constant temperature and pressure measurements at 64Hz with 64 samples. It is not possible to change the IC's mode, temperature_oversample_count or pressure_oversample_count on-the-fly so resetting the IC and operation parameteres is required. For instance, to set the mode to continuous pressure measurement at 1Hz with 2 samples:
-
-.. code-block:: python3
-
-    dps310.reset()
-    dps310.pressure_oversample_count = adafruit_dps310.SampleCount.COUNT_2
-    dps310.pressure_rate = adafruit_dps310.Rate.RATE_1_HZ
-    dps310.mode = adafruit_dps310.Mode.CONT_PRESSURE
-    dps310.wait_pressure_ready()
-
-
 
 Known Issues
 ============
-Library extensive features might not be compatible with memory limited boards. Library might not
-load in SAMD21 boards and others with 32KB of RAM or less.
+Library extensive features might not be compatible with memory limited boards. For these kind of
+boards you need to use the ``adafruit_dps310/basic.mpy``, the file needs to be in the ``mpy``
+format in order to fit in memory.
+For boards with more memory available you could use the code present
+in ``adafruit_dps310/advanced.py``. For usage refer to ``dps310_simpletest_advanced.py``
 
 
 Documentation

adafruit_dps310/__init__.py

@@ -3,12 +3,13 @@
 # SPDX-License-Identifier: MIT
 
 """
-`adafruit_dps310`
+`adafruit_dps310.advanced`
 ================================================================================
 
-Library for the DPS310 Precision Barometric Pressure Sensor
+Library for the DPS310 Precision Barometric Pressure Sensor. This is the advanced
+version. Includes some features not present in `adafruit_dps310.basic`
 
-* Author(s): Bryan Siepert
+* Author(s): Bryan Siepert, Jose David M.
 
 Implementation Notes
 --------------------
@@ -34,26 +35,10 @@
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_DPS310.git"
 
-# Common imports; remove if unused or pylint will complain
-import math
 from time import sleep
-from adafruit_bus_device import i2c_device
-from adafruit_register.i2c_struct import UnaryStruct, ROUnaryStruct
-from adafruit_register.i2c_bit import RWBit, ROBit
-from adafruit_register.i2c_bits import RWBits, ROBits
-
-_DPS310_DEFAULT_ADDRESS = 0x77  # DPS310 default i2c address
-_DPS310_DEVICE_ID = 0x10  # DPS310 device identifier
-
-_DPS310_PRSB2 = 0x00  # Highest byte of pressure data
-_DPS310_TMPB2 = 0x03  # Highest byte of temperature data
-_DPS310_PRSCFG = 0x06  # Pressure configuration
-_DPS310_TMPCFG = 0x07  # Temperature configuration
-_DPS310_MEASCFG = 0x08  # Sensor configuration
-_DPS310_CFGREG = 0x09  # Interrupt/FIFO configuration
-_DPS310_RESET = 0x0C  # Soft reset
-_DPS310_PRODREVID = 0x0D  # Register that contains the part ID
-_DPS310_TMPCOEFSRCE = 0x28  # Temperature calibration src
+from micropython import const
+from adafruit_register.i2c_bits import RWBits
+from adafruit_dps310.basic import DPS310
 
 # pylint: disable=no-member,unnecessary-pass
 
@@ -159,29 +144,45 @@ class SampleCount(CV):
     )
 )
 # pylint: enable=unnecessary-pass
-class DPS310:
+
+_DPS310_DEFAULT_ADDRESS = const(0x77)  # DPS310 default i2c address
+# _DPS310_DEVICE_ID = const(0x10)  # DPS310 device identifier
+
+# _DPS310_PRSB2 = const(0x00)  # Highest byte of pressure data
+# _DPS310_TMPB2 = const(0x03)  # Highest byte of temperature data
+_DPS310_PRSCFG = const(0x06)  # Pressure configuration
+_DPS310_TMPCFG = const(0x07)  # Temperature configuration
+# _DPS310_MEASCFG = const(0x08)  # Sensor configuration
+# _DPS310_CFGREG = const(0x09)  # Interrupt/FIFO configuration
+# _DPS310_RESET = const(0x0C)  # Soft reset
+# _DPS310_PRODREVID = const(0x0D)  # Register that contains the part ID
+# _DPS310_TMPCOEFSRCE = const(0x28)  # Temperature calibration src
+
+
+class DPS310_Advanced(DPS310):
     # pylint: disable=too-many-instance-attributes
     """Library for the DPS310 Precision Barometric Pressure Sensor.
+    This class contains some of other configurable features
 
     :param ~busio.I2C i2c_bus: The I2C bus the DPS310 is connected to.
     :param int address: The I2C device address. Defaults to :const:`0x77`
 
     **Quickstart: Importing and using the DPS310**
 
-        Here is an example of using the :class:`DPS310` class.
+        Here is an example of using the :class:`DPS310_Advanced` class.
         First you will need to import the libraries to use the sensor
 
         .. code-block:: python
 
             import board
-            import adafruit_dps310
+            from adafruit_dps310.dps310_advanced import DPS310_Advanced as DPS310
 
         Once this is done you can define your `board.I2C` object and define your sensor object
 
         .. code-block:: python
 
             i2c = board.I2C()   # uses board.SCL and board.SDA
-            dps310 = adafruit_dps310.DPS310(i2c)
+            dps310 = DPS310(i2c)
 
         Now you have access to the :attr:`temperature` and :attr:`pressure` attributes.
 
@@ -192,66 +193,11 @@ class DPS310:
 
     """
     # Register definitions
-    _device_id = ROUnaryStruct(_DPS310_PRODREVID, ">B")
-    _reset_register = UnaryStruct(_DPS310_RESET, ">B")
-    _mode_bits = RWBits(3, _DPS310_MEASCFG, 0)
-
     _pressure_ratebits = RWBits(3, _DPS310_PRSCFG, 4)
-    _pressure_osbits = RWBits(4, _DPS310_PRSCFG, 0)
-
     _temp_ratebits = RWBits(3, _DPS310_TMPCFG, 4)
-    _temp_osbits = RWBits(4, _DPS310_TMPCFG, 0)
-
-    _temp_measurement_src_bit = RWBit(_DPS310_TMPCFG, 7)
-
-    _pressure_shiftbit = RWBit(_DPS310_CFGREG, 2)
-    _temp_shiftbit = RWBit(_DPS310_CFGREG, 3)
-
-    _coefficients_ready = RWBit(_DPS310_MEASCFG, 7)
-    _sensor_ready = RWBit(_DPS310_MEASCFG, 6)
-    _temp_ready = RWBit(_DPS310_MEASCFG, 5)
-    _pressure_ready = RWBit(_DPS310_MEASCFG, 4)
-
-    _raw_pressure = ROBits(24, _DPS310_PRSB2, 0, 3, lsb_first=False)
-    _raw_temperature = ROBits(24, _DPS310_TMPB2, 0, 3, lsb_first=False)
-
-    _calib_coeff_temp_src_bit = ROBit(_DPS310_TMPCOEFSRCE, 7)
-
-    _reg0e = RWBits(8, 0x0E, 0)
-    _reg0f = RWBits(8, 0x0F, 0)
-    _reg62 = RWBits(8, 0x62, 0)
 
     def __init__(self, i2c_bus, address=_DPS310_DEFAULT_ADDRESS):
-        self.i2c_device = i2c_device.I2CDevice(i2c_bus, address)
-
-        if self._device_id != _DPS310_DEVICE_ID:
-            raise RuntimeError("Failed to find DPS310 - check your wiring!")
-        self._pressure_scale = None
-        self._temp_scale = None
-        self._c0 = None
-        self._c1 = None
-        self._c00 = None
-        self._c00 = None
-        self._c10 = None
-        self._c10 = None
-        self._c01 = None
-        self._c11 = None
-        self._c20 = None
-        self._c21 = None
-        self._c30 = None
-        self._oversample_scalefactor = (
-            524288,
-            1572864,
-            3670016,
-            7864320,
-            253952,
-            516096,
-            1040384,
-            2088960,
-        )
-        self.sea_level_pressure = 1013.25
-        """Pressure in hectoPascals at sea level. Used to calibrate :attr:`altitude`."""
-        self.initialize()
+        super().__init__(i2c_bus, _DPS310_DEFAULT_ADDRESS)
 
     def initialize(self):
         """Initialize the sensor to continuous measurement"""
@@ -268,69 +214,6 @@ def initialize(self):
         self.wait_temperature_ready()
         self.wait_pressure_ready()
 
-    # (https://github.com/Infineon/DPS310-Pressure-Sensor#temperature-measurement-issue)
-    # similar to DpsClass::correctTemp(void) from infineon's c++ library
-    def _correct_temp(self):
-        """Correct temperature readings on ICs with a fuse bit problem"""
-        self._reg0e = 0xA5
-        self._reg0f = 0x96
-        self._reg62 = 0x02
-        self._reg0e = 0
-        self._reg0f = 0
-
-        # perform a temperature measurement
-        # the most recent temperature will be saved internally
-        # and used for compensation when calculating pressure
-        _unused = self._raw_temperature
-
-    def reset(self):
-        """Reset the sensor"""
-        self._reset_register = 0x89
-        # wait for hardware reset to finish
-        sleep(0.010)
-        while not self._sensor_ready:
-            sleep(0.001)
-        self._correct_temp()
-        self._read_calibration()
-        # make sure we're using the temperature source used for calibration
-        self._temp_measurement_src_bit = self._calib_coeff_temp_src_bit
-
-    @property
-    def pressure(self):
-        """Returns the current pressure reading in hPA"""
-
-        temp_reading = self._raw_temperature
-        raw_temperature = self._twos_complement(temp_reading, 24)
-        pressure_reading = self._raw_pressure
-        raw_pressure = self._twos_complement(pressure_reading, 24)
-        _scaled_rawtemp = raw_temperature / self._temp_scale
-
-        _temperature = _scaled_rawtemp * self._c1 + self._c0 / 2.0
-
-        p_red = raw_pressure / self._pressure_scale
-
-        pres_calc = (
-            self._c00
-            + p_red * (self._c10 + p_red * (self._c20 + p_red * self._c30))
-            + _scaled_rawtemp * (self._c01 + p_red * (self._c11 + p_red * self._c21))
-        )
-
-        final_pressure = pres_calc / 100
-        return final_pressure
-
-    @property
-    def altitude(self):
-        """The altitude based on the sea level pressure (:attr:`sea_level_pressure`) -
-        which you must enter ahead of time)"""
-        return 44330 * (1.0 - math.pow(self.pressure / self.sea_level_pressure, 0.1903))
-
-    @property
-    def temperature(self):
-        """The current temperature reading in degrees Celsius"""
-        _scaled_rawtemp = self._raw_temperature / self._temp_scale
-        _temperature = _scaled_rawtemp * self._c1 + self._c0 / 2.0
-        return _temperature
-
     @property
     def temperature_ready(self):
         """Returns true if there is a temperature reading ready"""
@@ -434,44 +317,3 @@ def temperature_oversample_count(self, value):
         self._temp_osbits = value
         self._temp_scale = self._oversample_scalefactor[value]
         self._temp_shiftbit = value > SampleCount.COUNT_8
-
-    @staticmethod
-    def _twos_complement(val, bits):
-        if val & (1 << (bits - 1)):
-            val -= 1 << bits
-
-        return val
-
-    def _read_calibration(self):
-
-        while not self._coefficients_ready:
-            sleep(0.001)
-
-        buffer = bytearray(19)
-        coeffs = [None] * 18
-        for offset in range(18):
-            buffer = bytearray(2)
-            buffer[0] = 0x10 + offset
-
-            with self.i2c_device as i2c:
-
-                i2c.write_then_readinto(buffer, buffer, out_end=1, in_start=1)
-
-                coeffs[offset] = buffer[1]
-
-        self._c0 = (coeffs[0] << 4) | ((coeffs[1] >> 4) & 0x0F)
-        self._c0 = self._twos_complement(self._c0, 12)
-
-        self._c1 = self._twos_complement(((coeffs[1] & 0x0F) << 8) | coeffs[2], 12)
-
-        self._c00 = (coeffs[3] << 12) | (coeffs[4] << 4) | ((coeffs[5] >> 4) & 0x0F)
-        self._c00 = self._twos_complement(self._c00, 20)
-
-        self._c10 = ((coeffs[5] & 0x0F) << 16) | (coeffs[6] << 8) | coeffs[7]
-        self._c10 = self._twos_complement(self._c10, 20)
-
-        self._c01 = self._twos_complement((coeffs[8] << 8) | coeffs[9], 16)
-        self._c11 = self._twos_complement((coeffs[10] << 8) | coeffs[11], 16)
-        self._c20 = self._twos_complement((coeffs[12] << 8) | coeffs[13], 16)
-        self._c21 = self._twos_complement((coeffs[14] << 8) | coeffs[15], 16)
-        self._c30 = self._twos_complement((coeffs[16] << 8) | coeffs[17], 16)