Help! XBee Series 2 can't do bidirectional comm

Hi all,

I've got an Arduino board with an XBee Pro Series 2 shield, and another XBee Pro 2 with a USB-to-serial adapter. I need to establish bidirectional communications between the two. The computer XBee is configured as Coordinator AT, and the Arduino XBee is configured as Router/End Device AT.

The Arduino has a sketch on board to toggle an LED on/off if it receives a "H" or "L" from the computer respectively. It also has a push button switch that performs a Serial.println("Hello world!") when you push it.

I am able to send data to the Arduino - i.e., use MATLAB to send "H" and "L" from my computer to the Arduino - but nothing happens trying to send the "Hello world" string from the Ardunio to the computer.

Can someone please help me configure the two XBees so RX/TX work both ways?

Thanks a lot!

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