[Tutor] ctype exceptions.ValueError for function call

[Santhirakumaran, Gokul]

Hi,

I'm trying to use a SDK(dll file) with python ctypes to take measurement from a spectrometer. I some how got the deceive connected and took the measurement , but when I try to call one of its calculation function I'm getting  the "exceptions.ValueError: Procedure probably called with not enough arguments (8 bytes missing)" error.

I believe I have called the function with proper arguments and data types. I would really appreciate some help.

The Function:

mydll = ctypes.windll.LoadLibrary("D:\\WILD2\\tools\\WildVerification\\lib\\jeti_core.dll")
device = ctypes.c_int()
dvError = mydll.JETI_OpenDevice(0,ctypes.byref(device))

X_value = ctypes.c_float()
Y_value = ctypes.c_float()
Z_value = ctypes.c_float()

dvError = mydll.JETI_CalcXYZ(device,ctypes.byref(X_value),ctypes.byref(Y_value),ctypes.byref(Z_value))

Function Documentation:

3.112 JETI_CalcXYZ
This function returns the calculated tristimulus XYZ.
3.112.1 Prototype
DWORD JETI_CalcXYZ (DWORD dwDevice, FLOAT *fX, FLOAT *fY, FLOAT *fZ)
3.112.2 Parameters
Input
Name               Type                             Description                              Call
dwDevice          DWORD                       Handle to a device as                By value
returned by
JETI_OpenDevice

fX                     FLOAT*                         pointer to a variable                   By reference
where the tristimulus X
will be stored

fY                     FLOAT *                        pointer to a variable                   By reference
where the tristimulus Y
will be stored

fZ                     FLOAT *                        pointer to a variable                   By reference
where the tristimulus Z
will be stored

-
Gokul Santhirakumaran
Electrical Engineer(Co-op)

CHRISTIE
809 Wellington St. N.
Kitchener, ON, Canada N2G 4Y7
PH: +1 519-744-8005 x7313
www.christiedigital.com<http://www.christiedigital.com>

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