psychopy.hardware.pr.PR650

Class PR650

An interface to the PR650 via the serial port. example usage:: from psychopy.hardware.pr import PR650 myPR650 = PR650(port) myPR650.getLum()#make a measurement nm, power = myPR650.getLastSpectrum()#get a power spectrum for the last measurement N.B. :func:`psychopy.hardware.findPhotometer()` will locate and return any supported device for you so you can also do:: from psychopy import hardware phot = hardware.findPhotometer() print phot.getLum() :troubleshooting: Various messages are printed to the log regarding the function of this device, but to see them you need to set the printing of the log to the correct level:: from psychopy import log log.console.setLevel(log.ERROR)#error messages only log.console.setLevel(log.INFO)#will give a little more info log.console.setLevel(log.DEBUG)#will export a log of all communications If you're using a keyspan adapter (at least on OS X) be aware that it needs a driver installed. Otherwise no ports wil be found. Also note that the attempt to connect to the PR650 must occur within the first few seconds after turning it on.

Instance Methods

__init__(self, port, verbose=None)

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sendMessage(self, message, timeout=0.5, DEBUG=False)
send a command to the photometer and wait an alloted timeout for a response (Timeout should be long for low light measurements)

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measure(self, timeOut=30.0)
Make a measurement with the device.

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getLum(self)
Makes a measurement and returns the luminance value

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getSpectrum(self, parse=True)
Makes a measurement and returns the current power spectrum

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getLastLum(self)
This retrieves the luminance (in cd/m**2) from the last call to .measure() source code

getLastSpectrum(self, parse=True)
This retrieves the spectrum from the last call to .measure() source code

parseSpectrumOutput(self, rawStr)
Parses the strings from the PR650 as received after sending the command 'd5'.

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Method Details

measure(self, timeOut=30.0)

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Make a measurement with the device. For a PR650 the device is instructed to make a measurement and then subsequent commands are issued to retrieve info about that measurement

getSpectrum(self, parse=True)

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Makes a measurement and returns the current power spectrum

If parse=True (default):: The format is a num array with 100 rows [nm, power]
If parse=False (default):: The output will be the raw string from the PR650 and should then be passed to .parseSpectrumOutput(). It's slightly more efficient to parse R,G,B strings at once than each individually.

getLastSpectrum(self, parse=True)

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This retrieves the spectrum from the last call to .measure()

If parse=True (default): The format is a num array with 100 rows [nm, power]

otherwise: The output will be the raw string from the PR650 and should then be passed to .parseSpectrumOutput(). It's more efficient to parse R,G,B strings at once than each individually.

parseSpectrumOutput(self, rawStr)

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Parses the strings from the PR650 as received after sending the command 'd5'. The input argument "rawStr" can be the output from a single phosphor spectrum measurement or a list of 3 such measurements [rawR, rawG, rawB].