Timing Messages in ControlLogix

Hi all,
I want to show on a SCADA the time it take my ControlLogix to send and receive Messages to five AB504 PLC's. Does anyone have a recommendation on how I would do this. I know it sounds simple but I am over worked and confused.

Thanks a million.

Dave.

So I would assume Datahwy+ as the 5/04 does not have Etherner?

So you would send a [MSG] Write and a [MSG] Read to and from the Slicks.

Send the bit from the Ctrlgx to the 5/04 at the same time you start a timer and move the value of the timer ACC and reset the timer when you recieve the [MSG] read from the 5/04 ???????

Bob