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# Copyright (C) 2015 Chintalagiri Shashank 

# 

# This file is part of Tendril. 

# 

# This program is free software: you can redistribute it and/or modify 

# it under the terms of the GNU Affero General Public License as published by 

# the Free Software Foundation, either version 3 of the License, or 

# (at your option) any later version. 

# 

# This program is distributed in the hope that it will be useful, 

# but WITHOUT ANY WARRANTY; without even the implied warranty of 

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 

# GNU Affero General Public License for more details. 

# 

# You should have received a copy of the GNU Affero General Public License 

# along with this program.  If not, see <http://www.gnu.org/licenses/>. 

 

""" 

RadioShack 2200087 DMM Interface (:mod:`tendril.testing.instruments.RS2200087`) 

=============================================================================== 

 

This module provides the instrument object for RadioShack's 2200087 Digital 

Multimeter with PC interface. It uses the :mod:`driver2200087` module to 

handle the communication with the instrument, while subclassing the Twisted 

protocol of that module to provide one which produces 

:class:`tendril.utils.types.signalbase.SignalPoint` and 

:class:`tendril.utils.types.signalbase.SignalWave` objects instead, which 

contain Type objects from the :mod:`tendril.utils.types` module. This allows 

seamless integration with Tendril's :mod:`tendril.testing` module. 

 

.. rubric:: Usage example 

 

>>> from crochet import setup 

>>> setup() 

>>> from tendril.testing.instruments import get_instrument_object 

>>> o = get_instrument_object('RS2200087') 

>>> o.connect() 

>>> o.channel.get() 

>>> o.channel.reset_wave() 

>>> wave = o.channel.get_next_chunk() 

>>> wave += o.channel.get_next_chunk() 

 

.. rubric:: Module Contents 

 

.. rubric:: Classes 

 

.. autosummary:: 

 

    InstrumentRS2200087 

    DMMInputChannel 

    TendrilProtocol2200087 

    TendrilFactory2200087 

    factory 

 

 

.. rubric:: Processors 

 

.. autosummary:: 

 

    rex_list 

    voltage_processor 

    resistance_processor 

    capacitance_processor 

    frequency_processor 

    time_processor 

    current_processor 

    power_processor 

    duty_processor 

    hfe_processor 

    continuity_processor 

 

""" 

 

from tendril.utils import log 

logger = log.get_logger(__name__, log.DEFAULT) 

 

import re 

import copy 

from collections import deque 

 

from driver2200087.runner import InstProtocol2200087 

from driver2200087.runner import InstInterface2200087 

from driver2200087.runner import InstFactory2200087 

 

from tendril.utils.types.signalbase import SignalPoint 

from tendril.utils.types.signalbase import SignalWave 

 

from tendril.utils.types.time import TimeDelta 

from tendril.utils.types.time import timestamp_factory 

 

from tendril.utils.types import electromagnetic 

from tendril.utils.types import thermodynamic 

from tendril.utils.types import time 

from tendril.utils.types.unitbase import DummyUnit 

 

from tendril.testing.instrumentbase import InstrumentBase 

from tendril.testing.instrumentbase import InstrumentInputChannelBase 

from tendril.testing.instruments import connectionDone 

 

from decimal import Decimal 

from decimal import InvalidOperation 

 

 

def voltage_processor(m): 

    """ 

    Processor that converts a regex match of a Voltage string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the 

               Voltage regexs in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.Voltage` 

             class and its subclasses 

    :rtype: str 

 

    """ 

    num = m.group('number') 

    try: 

        rng = m.group('range') 

        if rng == 'K': 

            rng = 'k' 

        elif rng is None: 

            rng = '' 

    except IndexError: 

        rng = '' 

    rval = num + rng + 'V' 

    return rval 

 

 

def resistance_processor(m): 

    """ 

    Processor that converts a regex match of a Resistance string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the Resistance regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.Resistance` 

             class and its subclasses 

    :rtype: str 

 

    """ 

    num = m.group('number') 

    try: 

        rng = m.group('range') 

        if rng is None: 

            rng = '' 

        if rng == 'K': 

            rng = 'k' 

    except IndexError: 

        rng = 'E' 

    rval = num + rng 

    return rval 

 

 

def capacitance_processor(m): 

    """ 

    Processor that converts a regex match of a Capacitance string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the Capacitance regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.Capacitance` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    num = m.group('number') 

    rng = m.group('range') 

    if rng is None: 

        rng = '' 

    rval = num + rng + 'F' 

    return rval 

 

 

def frequency_processor(m): 

    """ 

    Processor that converts a regex match of a Frequency string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the Frequency regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.time.Frequency` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    num = m.group('number') 

    try: 

        rng = m.group('range') 

        if rng is None: 

            rng = '' 

    except IndexError: 

        rng = '' 

    rval = num + rng + 'Hz' 

    return rval 

 

 

def time_processor(m): 

    """ 

    Processor that converts a regex match of a Time string from 

    :mod:`driver2200087.serialDecoder` and returns a string 

    compatible with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the Time regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.time.TimeSpan` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    num = Decimal(m.group('number')) 

    try: 

        rng = m.group('range') 

        if rng is None: 

            rng = 1 

        elif rng == 'm': 

            rng = Decimal(1)/1000 

        elif rng == 'u': 

            rng = Decimal(1)/1000000 

        elif rng == 'n': 

            rng = Decimal(1)/1000000000 

    except IndexError: 

        rng = 1 

    rval = num * rng 

    return rval 

 

 

def current_processor(m): 

    """ 

    Processor that converts a regex match of a Current string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the Current regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.Current` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    num = m.group('number') 

    try: 

        rng = m.group('range') 

        if rng == 'K': 

            rng = 'k' 

        elif rng is None: 

            rng = '' 

    except IndexError: 

        rng = '' 

    rval = num + rng + 'A' 

    return rval 

 

 

def power_processor(m): 

    """ 

    Processor that converts a regex match of a PowerRatio string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the PowerRatio regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.PowerRatio` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    return m.group('number') + 'dBm' 

 

 

def hfe_processor(m): 

    """ 

    Processor that converts a regex match of a HFR string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the HFE regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.HFE` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    return m.group('number') + 'HFE' 

 

 

def duty_processor(m): 

    """ 

    Processor that converts a regex match of a DutyCycle string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the DutyCycle regexs 

              in :data:`rex_list` 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.DutyCycle` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    return m.group('number') + '%' 

 

 

def continuity_processor(m): 

    """ 

    Processor that converts a regex match of a Continuity string from 

    :mod:`driver2200087.serialDecoder` and returns a string compatible 

    with Tendril Unit Types. 

 

    :param m: :class:`re.match` object from one of the Continuity regexs 

              in :data:`rex_list`. 

    :return: String compatible with the 

             :class:`tendril.utils.types.electromagnetic.Continuity` class 

             and its subclasses 

    :rtype: str 

 

    """ 

    rval = 'CLOSED' 

    if m.group('string') == '0PEN': 

        rval = 'OPEN' 

    return rval 

 

#: List of regular expressions, each of which matches the string for one 

#: type of data from :mod:`driver2200087.serialDecoder`. Each element of 

#: the list is a `tuple`, containing the following elements: 

#: 

#: 0. Tendril type class from :mod:`tendril.utils.types` which is 

#:    applicable to the data point. 

#: 1. The compiled regular expression. 

#: 2. The applicable processor, which acts on the match object to produce 

#:    a string. If the processor is None, then the named match group 'string' 

#:    is used to instantiate the appropriate unit class. 

#: 

rex_list = [(thermodynamic.Temperature, 

             re.compile(ur'^(?P<string>[-?[0-9\\.]+[CFK])(?P<HOLD> HOLD)?$'), 

             None), 

            (electromagnetic.VoltageDC, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)?(?P<HOLD> HOLD)?( (?P<range>[munKM]) \(1e(?P<power>-?[\d]+)\))? VOLTS$'),  # noqa 

             voltage_processor), 

            (electromagnetic.VoltageAC, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+) AC(?P<AUTO> AUTO)?(?P<HOLD> HOLD)?( (?P<range>[munKM]) \(1e(?P<power>-?[\d]+)\))? VOLTS$'),  # noqa 

             voltage_processor), 

            (electromagnetic.CurrentDC, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)?(?P<HOLD> HOLD)?( (?P<range>[munKM]) \(1e(?P<power>-?[\d]+)\))? AMPS$'),  # noqa 

             current_processor), 

            (electromagnetic.CurrentAC, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+) AC(?P<AUTO> AUTO)?(?P<HOLD> HOLD)?( (?P<range>[munKM]) \(1e(?P<power>-?[\d]+)\))? AMPS$'),  # noqa 

             current_processor), 

            (electromagnetic.Continuity, 

             re.compile(ur'^(?P<string>0PEN) CONTINUITY(?P<HOLD> HOLD)?$'), 

             continuity_processor), 

            (electromagnetic.DiodeVoltageDC, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+) DIODE(?P<HOLD> HOLD)? VOLTS$'),  # noqa 

             voltage_processor), 

            (electromagnetic.Resistance, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)?(?P<HOLD> HOLD)?( (?P<range>[munKM]) \(1e(?P<power>-?[\d]+)\))? OHMS$'),  # noqa 

             resistance_processor), 

            (electromagnetic.Capacitance, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)?(?P<HOLD> HOLD)?( (?P<range>[munKM]) \(1e(?P<power>-?[\d]+)\))? FARADS$'),  # noqa 

             capacitance_processor), 

            (time.Frequency, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)?(?P<HOLD> HOLD)? Hz$'),  # noqa 

             frequency_processor), 

            (electromagnetic.PowerRatio, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<HOLD> HOLD)? dBm$'), 

             power_processor), 

            (electromagnetic.DutyCycle, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)(?P<HOLD> HOLD)? Percent$'),  # noqa 

             duty_processor), 

            (time.TimeSpan, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<AUTO> AUTO)?(?P<HOLD> HOLD)? SECONDS( (?P<range>[mun]) \(1e(?P<power>-?[\d]+)\))?$'),  # noqa 

             time_processor), 

            (electromagnetic.HFE, 

             re.compile(ur'^(?P<number>[-?[0-9\\.]+)(?P<HOLD> HOLD)? HFE$'), 

             hfe_processor), 

            ] 

 

# TODO Handle closed continuty 

# TODO Handle open diode 

# TODO Handle open resistor 

# TODO Handle shorted capacitor 

# TODO Handle Logic 

 

 

class TendrilProtocol2200087(InstProtocol2200087): 

    """ 

    This subclasses the twisted protocol from :mod:`driver2200087.runner` 

    which handles serial communications with 2200087 multimeters. It produces 

    :class:`tendril.utils.types.signalbase.SignalPoint` and 

    :class:`tendril.utils.types.signalbase.SignalWave` objects instead of 

    strings and deque objects, which contain Type objects from the 

    :mod:`tendril.utils.types` module. 

 

    This protocol exists and operates within the context of a twisted reactor. 

    Applications themselves built on twisted should be able to simply import 

    this protocol (or its factory). 

 

    Synchronous / non-twisted applications should directly use the 

    :class:`driver2200087.runner.InstInterface2200087` class instead, and 

    pass this protocol's factory to modify its behavior. 

 

    :param port: Port on which the device is connected. 

                 Default '/dev/ttyUSB0'. 

    :type port: str 

    :param buffer_size: Length of the point buffer in the protocol. 

    :type buffer_size: int 

    """ 

    def __init__(self, port, buffer_size): 

        InstProtocol2200087.__init__(self, port=port, buffer_size=buffer_size) 

 

    def reset_buffer(self, unitclass=DummyUnit): 

        """ 

        Resets the point buffer to a new 

        :class:`tendril.utils.types.signalbase.SignalWave` with the unitclass 

        as specified by the parameter. Any data presently within it will be 

        lost. 

 

        :param unitclass: Class of Unit that the Wave points are composed of. 

 

        """ 

        # logger.debug("Resetting buffer to type : " + repr(unitclass)) 

        self.point_buffer = SignalWave(unitclass, 

                                       spacing=TimeDelta(microseconds=100000), 

                                       ts0=timestamp_factory.now(), 

                                       buffer_size=1000, 

                                       use_point_ts=False) 

 

    def connectionLost(self, reason=connectionDone): 

        """ 

        This function is called by twisted when the connection to the 

        serial transport is lost. 

        """ 

        if repr(reason) == repr(connectionDone): 

            return 

        else: 

            print "Lost Connection to Device" 

            print reason 

 

    def next_chunk(self): 

        """ 

 

        :returns: The next chunk of data points in the form of a SignalWave 

        :rtype: :class:`tendril.utils.types.signalbase.SignalWave` 

 

        """ 

        rval = copy.copy(self.point_buffer) 

        self.point_buffer = SignalWave( 

            rval.unitclass, 

            points=deque([rval.pop()], maxlen=rval._buffer_size), 

            spacing=rval._spacing, 

            ts0=rval._ts0, 

            buffer_size=rval._buffer_size, 

            use_point_ts=rval._use_point_ts 

        ) 

        return rval 

 

    def _get_point(self, string): 

        """ 

        Processes a string returned by :mod:`driver2200087.serialDecoder` 

        and converts it into a 

        :class:`tendril.utils.types.signalbase.SignalPoint` instance composed 

        of the correct Unit class. 

 

        :return:  SignalPoint composed of the correct type and value from the 

                  string 

        :rtype: :class:`tendril.utils.types.signalbase.SignalPoint` 

 

        .. seealso:: :data:`rex_list` 

 

        """ 

        if string is None: 

            return SignalPoint(DummyUnit, None) 

        for rex in rex_list: 

            m = rex[1].match(string.strip()) 

            if m is not None: 

                if rex[2] is not None: 

                    rstring = rex[2](m) 

                else: 

                    rstring = m.group('string') 

                try: 

                    return SignalPoint(rex[0], rstring) 

                except (InvalidOperation, ValueError): 

                    # logger.error("Unable to make unit from string : " + 

                    # rstring + " : " + repr(rex[0])) 

                    return SignalPoint(rex[0], 0) 

        raise ValueError("String not recognized : " + string) 

 

    def frame_received(self, frame): 

        """ 

        Re-implements the Base class's frame_received function, producing 

        SignalPoints instead. When a signal point of a different type as 

        the point buffer is encountered, it resets the point buffer and 

        initializes it to the new type. 

 

        .. seealso:: :meth:`_get_point` 

 

        """ 

        frame = [byte.encode('hex') for byte in frame] 

        chunk = ' '.join(frame) 

        string = self._frame_processor(chunk) 

        point = self._get_point(string) 

        if not point.unitclass == self.point_buffer.unitclass: 

            self.reset_buffer(point.unitclass) 

        self.point_buffer.add_point(point) 

 

 

class TendrilFactory2200087(InstFactory2200087): 

    """ 

    This factory produces protocols integrated with Tendril unit classes, 

    producing SignalPoints and SignalWaves instead of strings. 

 

    See the :class:`driver2200087.runner.InstFactory2200087` documentation 

    for more detailed information. 

    """ 

    def buildProtocol(self, port='/dev/ttyUSB0', buffer_size=100): 

        """ 

        This function returns a TendrilProtocol2200087 instance, bound to the 

        port specified by the param port. 

 

        :param port: Serial port identifier to which the device is connected 

        :type port: str 

        :param buffer_size: Length of the point buffer in the protocol. 

                            Default 100. 

        :type buffer_size: int 

        """ 

        instance = TendrilProtocol2200087(port=port, buffer_size=buffer_size) 

        return instance 

 

 

#: Module's instance of the Protocol Factory. 

#: This should be used whenever the Protocol class 

#: is to be instantiated (as opposed to subclassed) 

factory = TendrilFactory2200087() 

 

 

class DMMInputChannel(InstrumentInputChannelBase): 

    """ 

    This class provides the bulk of the accessors to the instrument 

    for downstream use. 

 

    :param parent: The instrument of which this channel is a part of. 

    :param interface: The interface to the instrument. 

 

    """ 

    def __init__(self, parent, interface): 

        super(DMMInputChannel, self).__init__(parent) 

        self._interface = interface 

        self._wave = None 

 

    def get(self, unitclass=None, flush=True): 

        """ 

        Gets the latest data point in the channel's point buffer. By default, 

        it also flushes any older points from the buffer. This behavior can be 

        suppressed by passing flush=False. 

 

        :param unitclass: Unit class of which the data point is expected, or 

                          None if you don't care. 

        :param flush: Whether or not older points should be flushed. 

                      Default True. 

        :return: Latest datapoint. 

        :rtype: :class:`tendril.utils.types.signalbase.SignalPoint` 

 

        """ 

        value = self._interface.latest_point(flush=flush) 

        if unitclass is None or value.unitclass == unitclass: 

            return value 

        else: 

            raise TypeError 

 

    def get_next_chunk(self, unitclass=None): 

        """ 

        Gets the next chunk of data from the instrument channel. 

        Note that the chunk returned has already been removed from 

        the channel's point buffer. 

 

        :param unitclass: Unit class of which the data point is expected, 

                          or None if you don't care. 

        :return: Wave containing all but the latest data point in the 

                 channel's point buffer. 

        :rtype: :class:`tendril.utils.types.signalbase.SignalWave` 

 

        """ 

        chunk = self._interface.next_chunk() 

        if unitclass is None or chunk.unitclass == unitclass: 

            return chunk 

        else: 

            raise TypeError 

 

    def reset_wave(self): 

        """ 

        Resets the point / wave buffer in the channel 

        """ 

        self._interface.reset_buffer() 

 

 

class InstrumentRS2200087(InstrumentBase): 

    """ 

    This is the primary class provided by this module, and the object 

    generated by :meth:`tendril.testing.instruments.get_instrument_object` 

    is an instance of this class. All downstream Tendril application code 

    interfaces with this class, and through it, with :class:`DMMInputChannel`. 

 

    The primary code access to this class is though it's :attr:`channel` 

    property. 

 

    Instantiating this object results in the calling of :meth:`_detect`, 

    which prepares the object for use. 

 

    :ivar _dmm: The underlying instrument interface object 

    :type _dmm: :class:`InstInterface2200087` 

 

    """ 

    def __init__(self): 

        super(InstrumentRS2200087, self).__init__(None) 

        self._ident = "RadioShack 2200087 Digital Multimeter" 

 

    def connect(self): 

        self._detect() 

 

    def _detect(self): 

        """ 

        Creates and initializes the 

        :class:`driver2200087.runner.InstInterface2200087` object, which in 

        turn creates the protocol object and establishes the connection to 

        the device. 

 

        The instrument interface object created is stored in the object's 

        :attr:`_dmm` instance variable. 

 

        Subsequently, a :class:`DMMInputChannel` instance is instantiated 

        and linked to the interface. 

 

        """ 

        self._dmm = InstInterface2200087(pfactory=factory) 

        self._dmm.connect() 

        self._channels = [DMMInputChannel(self, self._dmm)] 

 

    def disconnect(self): 

        self._dmm.disconnect() 

 

    def data_available(self): 

        return self._dmm.data_available() 

 

    def configure(self, configuration): 

        raise NotImplementedError 

 

    @property 

    def channel(self): 

        """ 

 

        :return: The IntrumentInputChannel object. 

        :rtype: :class:`DMMInputChannel` 

 

        """ 

        return self._channels[0] 

 

    def reset_waves(self): 

        """ 

        Resets the point / wave buffers in the instrument's channels 

        """ 

        for channel in self._channels: 

            channel.reset_wave() 

 

 

if __name__ == "__main__": 

    i = InstrumentRS2200087()