Hello everybody, i've tried to upload the following sketch on the first Arduino + XBee (the "sender unit"):
/*
XBee_Send_Example3_modifiedRSSI
An example of using the Arduino board to send data from the
computer. In this case, the Arduino boards should send the RSSI value to the other XBee
The data can be sent from the Arduino serial monitor, or another
program like Processing (see code below), Flash (via a serial-net
proxy), PD, or Max/MSP.
created 2006
by David A. Mellis
modified 14 Apr 2009
by Tom Igoe and Scott Fitzgerald
modified 2009
by Marta86
http://www.arduino.cc/en/Tutorial/PhysicalPixel
*/
int RSSI=0; // holds the Received Signal Strength Value
void setup()
{
Serial.begin(9600);
}
void loop()
{
RSSI = Serial.read();
Serial.print(RSSI);
Serial.print('H');
delay(1000);
Serial.print('L');
delay(1000);
}
Then, i've uploaded this sketch to the second Arduino+XBee (the receiving unit):
/*
XBee_Receive_Example3_modifiedRSSI
An example of using the Arduino board to receive data from the
computer. In this case, the Arduino boards turns on an LED when
it receives the character 'H', and turns off the LED when it
receives the character 'L'.
The data can be sent from the Arduino serial monitor, or another
program like Processing (see code below), Flash (via a serial-net
proxy), PD, or Max/MSP.
The circuit:
* LED connected from digital pin 13 to ground
created 2006
by David A. Mellis
modified 14 Apr 2009
by Tom Igoe and Scott Fitzgerald
modified 2009
by Marta86
http://www.arduino.cc/en/Tutorial/PhysicalPixel
*/
const int ledPin = 13; // the pin that the LED is attached to
int incomingByte; // a variable to read incoming serial data into
#define analogPin 3
int RSSI=0; // holds the Received Signal Strength Value
int address=0; // holds the 16-bit address of the sender
void setup() {
// initialize serial communication:
Serial.begin(9600);
// initialize the LED pin as an output:
pinMode(ledPin, OUTPUT);
}
void loop() {
//address = Serial.read(); // the sixth byte is the low part of the address
//RSSI = Serial.read(); // the seventh byte is the RSSI value
// see if there's incoming serial data:
if (Serial.available() > 0) {
// read the oldest byte in the serial buffer:
incomingByte = Serial.read();
// if it's the RSSI value (ASCII 72), print the value on the serial:
if (Serial.read() == RSSI) {
Serial.print("RSSI");
}
// if it's a capital H (ASCII 72), turn on the LED:
if (incomingByte == 'H') {
digitalWrite(ledPin, HIGH);
Serial.print("HIGH");
}
// if it's an L (ASCII 76) turn off the LED:
if (incomingByte == 'L') {
digitalWrite(ledPin, LOW);
Serial.print("LOW");
}
}
//Serial.print(10,(100-RSSI)*2); // analog write a brightness roughly corresponding to distance
}
In this way I can see a series of <<-1HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL-1HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL87HL72HL73HL71HL72HL76HL79HL>>
on the serial monitor.. a certain value, "H" that means HIGH and "L" that means LOW. On the first and second time, the value was -1 when the receiving unit was disconnected, and was turning into 76, 79, 87, or whathever, once connected.. from the third time I've tried to disconnect the receiver, the sender unit simply continued to return 76, 79 or whathever continuously, like nothing was happened..
On the receiving unit, I simply have my LED turning on and off depending on the char received, and LOWHIGHLOWHIGH.. is written on the serial monitor.. but not the RSSI value! 
Could anyone help me? I need to have the RSSI value in order to finish my project!! 
Thnks a lot!
Marta
I am working with XBee shields Series 2 (or Znet 2.5, whatever you prefer). All in all I have 6 shields that are mounted to Arduino Duemilanoves which have some LEDs and Sensor technique connected. One additional Arduino has the MCU removed and works as the network coordinator (Znet 2.5 Coordinator AT), the other modules are configured as Znet 2.5 Router/End Device(s). The communication is working fine, I can send and receive signals and messages and everything else. But I was wondering if it is somehow possible to force the shields to send a RSSI signal permanent or at least on request... So the best would be if all the modules send the signal strength to the coordinator who will send them to the PC and display them on any kind of graphical interface (my dream :
And for now it doesn´t matter that much how to display the signal strength (Processing or any other program). Or maybe if somebody knows how the Range Test with X-CTU is performed? Because this one is working, too but only if I configure the devices with each other DH/DL, SH/SL address and let them send the same messages at the same time. But the principle would be the same I guess?