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They are located in Simulink\libRnlibRXXXXy\user\src\Softing\CanAc2 where 'RnRXXXXy' is one of the Matlab releases supported by RT-LAB. There is one file for each CanAc2 block : canac2_ctl_win32.c, canac2_recv_win32.c,canac2_send_win32.c and canac2_monitor_win32.c.
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RT-LAB release comes with a pre-compiled library of (quasi-)empty functions. As the user customizes the source codes of the functions, he will need to recompile the library. A Visual C++ project is provided in the same directory as the source codes. During compilation, the library, libOpalCanAc2_PCIwin32RTRn.lib, is placed in the directory Simulink\libRnlibRXXXXy\user\lib (replace Rn RXXXXy by the actual Matlab release number).
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