How to differentiate an Xbee transmitter from another with a single coordinator?

Have 4 Xbee nodes, one in api coordinator mode, and 3 configured as end devices. The end devices are all transmitting at the same time, 1 at 20hz, and 2 at 1 hz. I see all the packets on my XCTU console but it is just one endless stream on the com port for the coordinator. How do I differentiate between each transmitter? Or is there a way to set up the coordinator to take turns listening to each transmitter?

I should note there is no arduino in this set up anywhere. The 3 end devices have their Din ( pin 3) pins wired directly to my sensor which is in an rs232 stream mode and just spits out data forever.