The standard says:
6.2.7.1 Port ID / Response Type field for Controller Generated Messages
For Controller generated messages (GET_COMMAND, SET_COMMAND, and
DISCOVERY_COMMAND), the Port ID field shall be set in the range of 1-255 identifying
the Controller Port being used, such that the combination of Source UID and Port ID will uniquely
identify the controller and port where the message originated.
It's not clear in our case if this should be per universe, or per plugin port (i.e. multiple ports per universe). I suspect it should be per plugin port, as a physical lighting desk with two ports would need two UARTs, and hence would likely have two port IDs.
The standard says:
It's not clear in our case if this should be per universe, or per plugin port (i.e. multiple ports per universe). I suspect it should be per plugin port, as a physical lighting desk with two ports would need two UARTs, and hence would likely have two port IDs.