Right now I basically assembled all parts of the board and the Cubetto but it looks like the wireless communication is not working.

List of Problems:

• Cubetto did not initialize. I could hear the motors stutter but they would not move. Looks like the 4 AA batteries don’t deliver enough juice. Now I’m temporary using an old cell phone charger to deliver the power. No more wireless 😉 but it helps me troubleshooting.
  Might have to go for LiPo batteries.
• I then tried it out with the XBees installed on the Mega and the Uno (via Wireless sd shields) respectively. But nothing happened.
  Looking at the board’s output over serial I can see that the commands are being sent. And when connecting to Cubetto using the USB cable it also initializes correctly and executes commands that I send from the laptop via serial.

So I made a step back and just wanted to setup a basic XBee connection between the two Arduinos:

I came across this tutorial from Instructables but it is not working for me.

Setup
Transmitter:
– Mega 2560
– Arduino Wireless Protoshield SD
– XBee 2mW Wire Antenna – Series 2 (ZigBee Mesh)

Code:

void setup() {
  // initialize serial communication:
  Serial.begin(9600);
}

void loop(){
  delay(1000);
  Serial.println('h');
  delay(1000);
}

I have the switch on the shield on “USB” while uploading and can see “h”‘s printed in the serial window after uploading. Switching to “Micro” after that.

Receiver:
– Uno R3
– Arduino Wireless Protoshield SD
– XBee 2mW Wire Antenna – Series 2 (ZigBee Mesh)

Code:

int sentDat;

void setup() {
  Serial.begin(9600);
  pinMode(2, OUTPUT);
}

void loop() {
  if (Serial.available() > 0) {
    sentDat = Serial.read();

    if(sentDat == 'h'){
      digitalWrite(2, HIGH);
      delay(1000);
      digitalWrite(2, LOW);
    }
  }
}

Again, having the switch to USB when uploading and seeing the led blink when sending an “h” over serial. Then switching to “Micro”.

And then: Nothing!

How can I troubleshoot this? Any help appreciated.

[UPDATE]

I yanked the shield from the Mega and crossed tx/rx from the Mega to the shield. I also connected the 6 isp connections plus 5v, 3.3v and GND.
I then connected Mega’s rx with Uno’s rx and tx with tx with wires and my blink sketch worked!
I had the switches on the shields both to USB.

But then, when I remove the rx/tx wires the communication is dead. I switched the shield to Micro mode and back to USB, i played around with switching rx / tx… but no luck.

Not sure if I need to make more connections from the Mega to the shield… unfortunately it’s not on shieldlist.org.

[/UPDATE]