[XNET][CVI2013] Check is CAN port communication is active and check for periodic signal

Hello,

I'm using CVI 2013 and the NI Automotive Diagnostic Command Set 1.1 toolkit. 

Board NI PXI 8513 (2 CAN bus)

I want to know how can I check is a CAN port communication is active, and if so, how can I check if a periodic signal is currently about to be sent ?

No problem if they are two separate functions. 

Best regards,

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