Hi guys,
I am trying to build a GPS tracking collar for my dog using: Xbees, an adafruit ultimate GPS module, and a Cheapduino (Cheapduino (5PCS) - DFRobot). I know it's not strictly Arduino, but it uses the Arduino NG bootlader \w ATmega8 microprocessor and I don't think there is a better place for a post like this.
Anyways, my problem is with trying to use the UART Tx and Rx pins on the cheapduino. I know the soldering connects are fine because when I connect the GPS module directly to the UART pins and open a serial monitor in the Arduino IDE, I get the NMEA outputs which I should be getting. However, when I read the data into the cheapduino and send that data over the xbees, it doesn't work. I also know my Xbees are setup fine because when I connect the GPS module directly to the xbees and open a terminal, I get the proper NMEA output. So it looked like the reading/writing from the Cheapduino was the problem.
So I set up a simple circuit to test out my theory. I am trying to send something over the xbees and have the cheapduino basically echo it back. Here is the code:
void setup()
{
Serial.begin(9600);
}
void loop()
{
while (Serial.available() ) {
Serial.write(Serial.read()); // reply with whatever you receive
}
}
Here is the picture of my setup:
and here is a schematic of it:
On the receiving Xbee, it is connected directly to my computer via an FTDI adapter.
When I open the serial monitor on the computer, I don't get anything. It appears that when I use Serial to output stuff directly from the cheapduino to the computer terminal, everything works fine. I can print stuff to the terminal and I can send commands. However, when I disconnect from the computer and try to read/write over the UART pins, it doesn't work.
I am fairly new to Arduino programming, but from everything I have seen on the internet, this should work. I have also tried loading the Dimmer example onto the cheapduino and controlling an LED, but that doesn't work either... and I did change the pin number to match the Cheapduino in the example. I also have selected the correct board type and baud rate in the Arduino IDE. I have spent two days googling and trying to get this to work, but I am stumped.
Here is the documentation for the Xbee: http://ftp1.digi.com/support/documentation/90002173_N.pdf
Here is the closest thing to documentation for the Cheapduino: CheapDuino_(SKU_DFR0236)-DFRobot
Any help would be appreciated. Thanks in advance.
Cheers,
- Peter