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They are located in Simulink\libRXXXXy\user\src\Softing\CanAc2 where 'RXXXXy' 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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