Acuity does not have OGP support for the main busses .. you can get this from the Aux Buses but no the MEs..
If you want to setup your own script like in the Acuity DashBoard custom panel you will see that you can send a rosstalk command with the ? at the end instead of the paramater that would set it ... ie XPT ME:1:PST:? would then have it reply to you (have to setup your own listener) with the information of which source was on the PST bus...
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Les O'Reilly
Director - Switcher Product Management
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