I'm trying to get my LabJack u3 working with matlab on a mac. I didn't realize the matlab support was mainly for windows and I'm by no means a c programmer, so that usually means I try something, look up the generated error and/or write inane questions to forums while trying to figure things out.
So I have the U3 examples that came with the mac installation of the exodriver compiling in C through the makefile and was hoping that it would be somewhat straightforward to compile this code with mex to run in matlab. I'm at a bit of a loss how to convert the makefile to mex format so am trying to just compile an individual c program. When I try (I can't seem to get libraries to work with mex, so leaving those off for now):
mex -largeArrayDims u3Stream.c
I get the following:
Building with 'Xcode with Clang'.
Error using mex
Undefined symbols for architecture x86_64:
"_LJUSB_Read", referenced from:
_ConfigIO_example in u3Stream.o
_StreamStop in u3Stream.o
_StreamConfig_example in u3Stream.o
_StreamStart in u3Stream.o
"_LJUSB_Stream", referenced from:
_StreamData_example in u3Stream.o
"_LJUSB_Write", referenced from:
_ConfigIO_example in u3Stream.o
_StreamStop in u3Stream.o
_StreamConfig_example in u3Stream.o
_StreamStart in u3Stream.o
"_closeUSBConnection", referenced from:
_main in u3Stream.o
"_extendedChecksum", referenced from:
_ConfigIO_example in u3Stream.o
_StreamConfig_example in u3Stream.o
"_extendedChecksum16", referenced from:
_ConfigIO_example in u3Stream.o
_StreamConfig_example in u3Stream.o
_StreamData_example in u3Stream.o
"_extendedChecksum8", referenced from:
_ConfigIO_example in u3Stream.o
_StreamConfig_example in u3Stream.o
_StreamData_example in u3Stream.o
"_getAinVoltCalibrated", referenced from:
_StreamData_example in u3Stream.o
"_getAinVoltCalibrated_hw130", referenced from:
_StreamData_example in u3Stream.o
"_getCalibrationInfo", referenced from:
_main in u3Stream.o
"_getTickCount", referenced from:
_StreamData_example in u3Stream.o
"_mexFunction", referenced from:
-exported_symbol[s_list] command line option
"_normalChecksum8", referenced from:
_StreamStop in u3Stream.o
_StreamStart in u3Stream.o
"_openUSBConnection", referenced from:
_main in u3Stream.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
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The undefined symbols indicate the compiler can't find those functions. u3Stream.c requires u3.c and links to liblabjackusb.dylib. See if something like this works:
mex -largeArrayDims -llabjackusb u3Stream.c u3.c
You may need to include the header files (u3.h and labjackusb.h) to your list of files. If -llabjackusb doesn't work, try -lliblabjackusb instead.
Definitely getting closer:
mex -largeArrayDims -llabjackusb u3Stream.c u3.c
Building with 'Xcode with Clang'.
Error using mex
Undefined symbols for architecture x86_64:
"_mexFunction", referenced from:
-exported_symbol[s_list] command line option
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
So if I copy a generic file called mexFunction.c (found from a search on matlab mexFunction.c) to the directory I'm trying to compile in and then do this:
mex -largeArrayDims -llabjackusb u3Stream.c u3.c mexFunction.c
I get:
Building with 'Xcode with Clang'.
MEX completed successfully.
Which is pretty exciting. I don't have my labJack with me so can't see if this actually does anything, but fingers crossed!!