Fake getter/ real setter

comments

Except for 2-3 exception, the Newport 842-PE doesn't have real getter functions, but it has many setters. But is has a function (sta) that read device status for a lot of parameters. The previous file do a fake getter/setter.

def status
returns a dict where the key/value pairs correspond to each device parameter.

At device initialisation, the device's configuration is read and stored in self.DeviceStatus

The getter scale just read corresponding parameter in self.DeviceStatus and return it.

The setter scale actually write to the device to change its state.

gistfile1.py

# -*- coding: utf-8 -*-
"""
    lantz.drivers.newport.842PE
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Newport 842-PE powermeter

    :copyright: 2013 by Lantz Authors, see AUTHORS for more details.
    :license: BSD, see LICENSE for more details.
"""
import time
import warnings

from lantz import Action, Feat
from lantz.serial import SerialDriver
from lantz.errors import InstrumentError


class N842PE(SerialDriver):
    """Newport 842-PE powermeter
    """

    ENCODING = 'ascii'

    RECV_TERMINATION = '\r\n'
    SEND_TERMINATION = '\r\n'

    BAUDRATE = 115200
    BYTESIZE = 8
    PARITY = 'none'
    STOPBITS = 1

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.initialize()
        self.DeviceStatus = self.status  # Read the device status
 
    Scales = ('auto', '1p', '3p', '10p', '30p', '100p', '300p', '1n',
              '3n', '10n', '30n', '100n', '300n', '1u', '3u', '10u',
              '30u', '100u', '300u', '1m', '3m', '10m', '30m',
              '100m', '300m', '1', '3', '10', '30', '100', '300',
              '1k', '3k', '10k', '30k', '100k', '300k', '1M', '3M',
              '10M', '30M', '100M', '300M',)
    
    @Feat(values=set(Scales))
    def scale(self):
        out = self.DeviceStatus['CurrentScale']
        return self.Scales[out]

    @scale.setter
    def scale(self, value):
        """This command is used to force the display of the current data into a
        specific range. (ssa)
        """
        self.query('*ssa {}'.format(value))
        self.DeviceStatus = self.status # update cached device status

    # The device is a bit buggy for this one as it return the info with 3 \n\r.
    # So the hack here repare it.
    # We have to read it 3 times.
    # In addition, it seems to never return the last field (dBm).
    @Feat()
    def status(self):
        """This command is used to query the current device status. (sta)
        Returns a dict containing device variables's values.
        """
        DeviceStatus = {}
        out1 = self.parse_query('*sta', format='Head Type: {}\t'
                                'Head Version: {}\t'
                                'Head Serial Number: {}\t{}\t'
                                'Calibration Sensitivity: {} V/W\t'
                                'Default WaveLength: {} nm\t'
                                'Active Sensitivity: {} V/W\t'
                                'Active WaveLength: {} nm\t'
                                'Scale Min Power : {}\t'
                                'Scale Max Power: {}\t'
                                'Scale Min Energy : {}\t'
                                'Scale Max Energy: {}\t'
                                'Current Scale: {}\t'
                                'Energy Mode: {}\t'
                                'Anticipation: {}\t'
                                'Trig Level: {}%\t'
                                'Zero Offset: {}\t'
                                'Multiplier #1: {}\t'
                                'Offset #1: {}\t'
                                'Multiplier #2: {}\t'
                                'Offset #2: {}\t'
                                'Currently Logging data:  {}\t'
                                'Analog Output:  {}\t'
                                'Resolution: {}\t'
                                'Currently Calculating Stats:  {}\t'
                                'High Resolution Display:  {}\t'
                                'Min Wavelength index: {}\t'
                                'Max Wavelength index: {}\t'
                                'Upper Bound: {}\t'
                                'Lower Bound: {}\t'
                                'Reference Value: {}\t'
                                'P/F Status: {}\t'
                                'Threshold: {}')
        out1.append(self.parse_query('', format='Attenuator: {}'))
        out1.append(self.parse_query('', format='AutoScale: {}'))

        DeviceStatus['HeadType'] = out1[0]  # WattMeter, Photodiode
        #DeviceStatus['Head Version'] = out1[1]  # Is that really the head version?
        DeviceStatus['SerialNumber'] = out1[2]
        DeviceStatus['HeadName'] = out1[3]
        DeviceStatus['CalibrationSensitivity'] = out1[4] # unit V/W
        DeviceStatus['CalibrationWavelength'] = out1[5]  # unit nm, seems non-sense for photodiode
        DeviceStatus['ActiveSensitivity'] = out1[6]  # unit V/W
        DeviceStatus['ActiveWavelength'] = out1[7]  # unit nm
        DeviceStatus['ScaleMinPower'] = out1[8]
        DeviceStatus['ScaleMaxPower'] = out1[9]
        DeviceStatus['ScaleMinEnergy'] = out1[10]  # is N/A for photodiodes
        DeviceStatus['ScaleMaxEnergy'] = out1[11]  # is N/A for photodiodes
        DeviceStatus['CurrentScale'] = int(out1[12])
        DeviceStatus['EnergyMode'] = 1 if (out1[13] == 'On') else 0
        DeviceStatus['Anticipation'] = 1 if (out1[14] == 'On') else 0
        DeviceStatus['TrigLevel'] = out1[15]  # unit %
        DeviceStatus['ZeroOffset'] = out1[16]
        DeviceStatus['Multiplier'] = [out1[17], out1[19]]
        DeviceStatus['Offset'] = [out1[18], out1[20]]
        DeviceStatus['CurrentlyLoggingdata'] = 1 if (out1[21] == 'Yes') else 0
        DeviceStatus['AnalogOutput'] = 1 if (out1[22] == 'On') else 0
        DeviceStatus['Resolution'] = out1[23]
        DeviceStatus['CurrentlyCalculatingStats'] = 1 if (out1[24] == 'Yes') else 0
        DeviceStatus['HighResolutionDisplay'] = 1 if (out1[25] == 'On') else 0
        DeviceStatus['MinWavelengthindex'] = out1[26]  # For photodiodes, it's the minimum wavelength in nm
        DeviceStatus['MaxWavelengthindex'] = out1[27]  # For photodiodes, it's the minimum wavelength in nm
        DeviceStatus['UpperBound'] = out1[28]
        DeviceStatus['LowerBound'] = out1[29]
        DeviceStatus['ReferenceValue'] = out1[30]
        DeviceStatus['P/FStatus'] = out1[31]  # N/A, .... (To be tested)
        DeviceStatus['Threshold'] = out1[32]  # On, Off (To be tested)
        DeviceStatus['Attenuator'] = 1 if (out1[33] == 'On') else 0  # On, Off or N/A. N/A is when there is not
        DeviceStatus['AutoScale'] = 1 if (out1[34] == 'On') else 0
        
        return DeviceStatus


    def query(self, command, *, send_args=(None, None),
              recv_args=(None, None)):
        answer = super().query(command, send_args=send_args,
                               recv_args=recv_args)
        if answer == 'ERROR':
            raise InstrumentError
        return answer

if __name__ == '__main__':
    import argparse
    import lantz.log

    parser = argparse.ArgumentParser(description='Newport 842-PE powermeter')
    parser.add_argument('-i', '--interactive', action='store_true',
                        default=False, help='Show interactive GUI')
    parser.add_argument('-p', '--port', type=str, default='17',
                        help='Serial port to connect to')

    args = parser.parse_args()
    lantz.log.log_to_screen(lantz.log.DEBUG)
    with N842PE(args.port) as inst:
        if args.interactive:
            from lantz.ui.qtwidgets import start_test_app
            start_test_app(inst)
        else:
            print('Testing instrument...')

            print(inst.scale)
            inst.scale = '30u'
            print(inst.scale)

            time.sleep(1)

            print(inst.scale)
            inst.scale = '300n'
            print(inst.scale)