To import PR655, you can either use:
from psychopy_photoresearch.pr import PR655
or, any time after psychopy.plugins.activatePlugins has been called:
from psychopy.hardware.pr import PR655
An interface to the PR655/PR670 via the serial port.
example usage:
from psychopy.hardware.pr import PR655
myPR655 = PR655(port)
myPR655.getLum() # make a measurement
nm, power = myPR655.getLastSpectrum() # get a power spectrum for the
last measurement
NB 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())
If the device isn’t responding try turning it off and turning it on again, and/or disconnecting/reconnecting the USB cable. It may be that the port has become controlled by some other program.
Fetches (from the device) the color temperature (K) of the last measurement
list: status, units, exponent, correlated color temp (Kelvins), CIE 1960 deviation
measure() automatically populates
pr655.lastColorTemp with the color temp in Kelvins
This retrieves the luminance (in cd/m**2) from the last call to
.measure()
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.
Fetches (from the device) the last CIE 1931 Tristimulus values
list: status, units, Tristimulus Values
measure() automatically populates pr655.lastTristim
with just the tristimulus coordinates
Fetches (from the device) the last CIE 1976 u,v coords
list: status, units, Photometric brightness, u, v
measure() automatically populates pr655.lastUV
with [u,v]
Fetches (from the device) the last CIE 1931 x,y coords
list: status, units, Photometric brightness, x,y
measure() automatically populates pr655.lastXY
with [x,y]
Makes a measurement and returns the luminance value
Makes a measurement and returns the current power spectrum
parse=True (default):The format is a num array with 100 rows [nm, power]
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.
Make a measurement with the device.
This automatically populates:
.lastLum
.lastSpectrum.lastCIExy
.lastCIEuv
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].
Send a command to the photometer and wait an allotted timeout for a response (Timeout should be long for low light measurements)