How to have one port send data to all the ports in a 16 port Devicemaster
If the data is entering the DeviceMaster via the physical serial port (via cable), then the standard UDP configuration can take place.  In this document, we will explain the unique configuration that needs to occur if the source data input is via a com port or socket connection.
The data is assumed to enter via Port 1 either through the Com port driver or through Socket communications (Port 8000).  Because that port is open and in use, it can't be used for UDP communication.  Data will need to go into a secondary port (port 2) so it isn't already in use and is available via UDP.  The below configuration example is for a 16 port DeviceMaster where data coming into port 1, is transferred to port 2 and is distributed to ports 3-10, then 10-16.
Port 2 configuration sending data to physical ports 3-10 (7002-7009)

On Port 10 (7009), configure the data to send to ports 11-16 (7010-7015)

The attention to detail that people miss is all ports with the exception of port 1, MUST have this checkmarked (below) the example is for physical port 5 (7004)

To recap:
1.  Com 1 (or 3) is configured to go to Physical Port 1 in the driver.
2.  A Null Modem cable goes from Physical Port 1 to 2 so data coming into port 1 is transferred to port 2.  This way, the port is not already open which would be the case in physical port 1 (Being used by the Com port)
3.  The configuration for physical port 2 send the data via UDP to ports 3-10
4.  Port 10 is configured to send it's data from port 10 to 11-16.