Hi, I am having problems getting a XBee DTE Serial Board to work with some devices and I can’t seem to figure out why. The XBee DTE Serial Board is powered by a 4xAA battery pack connected to the power pin which seems to be powering the board because the ASSOC light lights up then starts to blink yet I get no contact with it from my computer through an XBee USB board. Now if I connect it to an old RS232 based programmer of mine and turn on the programmer which itself is powered by a wall adapter I finally get contact with the XBee DTE board from my computer and can use my programmer wireless. Should I turn off the programmer then I lose contact with the XBee DTE board again so I tried to connect the XBee DTE board to the programmer without having the battery pack connected to the XBee DTE board because I suspected the programmer might giving the XBee power, but without the battery pack the XBee DTE board was completely dead which means that the programmer does not give any power to the XBee DTE board.
Besides this old programmer of mine I tried to use the XBee DTE board with a RS232 to TTL converter which has no additional power options and TV box which is powered by a wall adapter also, both of which did not work with the XBee DTE board, only the old RS232 programmer works and I can not understand why. Can anyone shed some light on why the XBee DTE board with some devices, but not with all and if possible how to make it work? Thanks.
Thank you for your answer and sorry for my late reply. I am using 2 XBee ZNet 2.5 1mW with chip antenna, one on the XBee USB board configured as Coordinator AT and the other on the XBee DTE board configured as End Device AT. The voltage on the wall adapter for the old RS-232 based programmer is 12V and I used a pin monitor see pins are used by the programmer. Turns out only GND, RX and TX are needed so that was not much help because I know my other devices only need those also.
Although there was one thing you mentioned which turns out does make a difference and that is the baud rate. I changed the baud rate on the computer and programmer and it worked on all baud rates I tried. What I didn’t know was that there was a baud rate option on the XBee modules themselves so the XBee modules remained at 9600. I now suspect that the programmer always starts in 9600 and then is told which baud rate to use, therefore although I believed I had changed the baud rate everything was still running at 9600. After I changed the baud rate in the XBee modules to 115200 which is the baud rate hard coded in the device I am trying to use, I finally managed to get a connection.
Now unfortunately another problem arose, although I can get a connection and start to send/receive data after a couple of seconds I start receiving messages on the computer about either unknown answers or about timeouts. Do you have any idea of what might be the issue now and why it is failing to work? Thanks.
Thank you for your reply and yes I know it is up to me to debug now, I was just hoping there might have been another setting or option I had forgotten to configure which would be causing this type of issues. My problem is that although I have full control of the software on the computer and can make any changes I want there, the other side where the XBee DTE board is connected to is essentially a black box with no configuration options.
What I suspect is that a lot of data is pushed through when initiating the communication and this somehow saturates the XBee link so that the packages received are not complete. This is what I believe the “unknown answer received” message refers to. I have played with the Packetization Timeout option, but without success though I am not sure I understand exactly what it does either so I might have used it wrong. Do you or anyone else have any idea what I might try to make it work? Thanks.
Thank you for your help and for telling me about the Digi forum. I was not aware that Digi had a forum of their own, but now I will ask there and see what answers I get. Should I get any useful information then I will come back and post it here too just in case other people experience similar problems. Thanks.
Without having the module in hand, it sounds like a voltage issue. The Droids XBee DTE Serial Board can theoretically accept Vin as low as 4V (4x 1.2V = 4.8V or 6V), though its important to check the requirements of your XBee module. USB would supply the board at 5V, and you did not state the voltage of the wall adapter. Secondly, did you check the Baud rate at which you are sending data from your computer to the XBee module? Your “old programmer” may be communicating at the right Baud, but not your computer. As a last resort, you can use one of the diagnostic tools from Digi associated with your product.
Since you know the modules themlseves are working and can transmit/receive, it’s now up to you to debug the system as a whole. The timeouts can come from a number of different areas, from low power to one of the devices, to the code itself. Can you create a simple program that sends (linearly) increasing numbers and the system simply displays them on the other end? Debug section by section to find the root cause, or at least verify which sections are not the cause of the problem. Sorry not to be able to help more than this. Perhaps the user community has some ideas or related forums?
Another option for support (since this seems quite specialized) is the Digi Forum. Take a look at the specific section for XBee modules. We try to address all technical problems, though some are best addressed directly by the manufacturer. Keep us posted as to your progress and we again encourage the user community here to offer their suggestions or experience.
