Xbee Interfacing with Arduino-Part-2

Hey All,

I have a doubt regarding Xbees. I am using 2 seperate Xbee S2 and Arduino (Basically 1 arduino & Xbee S2 at Tx and one pair at Rx)

Now initially I need the values to be sent from Tx to Rx. In later stages I need to send some other values from Rx to Tx. To be more specific I need both Xbee's to send and receive values.

But the thing is, in all the Xbee discussions people state One Xbee must be Coordinator and other must Be End device or things of that sort.. Does this mean the Transmission can take place in only one direction (from Tx to Rx) ??

What should I keep , " IF " both the Xbee/s must Send as well as Receive the data .. should i set both of them to End device or Both to coordinator or is there any other way to do it ?? I am new to Xbees interfacing please help .

For those who are quite familiar with Xbee interfacing and stuffs , I also have a problem which is mentioned in this post

https://forum.arduino.cc/index.php?topic=382549.0

I would be thankful if someone could explain elaborately in step by step manner on this as i am new to Xbee's.

Regards, Gireesh