Data rececived over UART not being sent over RF?

XBee & XBee Gateway XBee - 802.15.4
1

Hello fellow Xbee developers!

I have an XB24 connected to a PIC24 trying to send data to another XB24 or XBP24 (I have tried both). This will be part of a much more complex project but I am struggling to get this basic setup to operate.

Both Xbee modules are connected to X-CTU on separate PCs so that I can see the data in and out of the modules in the terminal window. I can send data from the PIC to the XB24 over UART. The data appears perfectly in the terminal window of the connected XB24 module but is not sent over RF to the other XB module.

The modules are configured correctly to communicate because if the ‘assemble packet’ option is used in the terminal window of either module then the data is recieved at the remote module.

Strangely enough if the PIC is sending a stream of data over UART to the module and I press the ‘enter’ key in the terminal then the data sends over RF! This confuses me as I didn’t think that the carraige return had anything to do with paketisation or sending data - it is only used for commands?

Why isn’t the data that the module recieves over UART being sent over RF? The modules are setup in tranparent mode and my understanding was that his should act as a serial line?

FIEMWARE VERSION - tried with both 10CD and 10E8;
CE = 0;
Have tried various RO = 0, RO = 3;

Any ideas? I hope that I’m missing something blindingly obvious! Thanks in advance.
Rory

2

I’ll have a go at this, though I’m not sure that from your description I can really picture the situation.

You say that both modules are connected to X-CTU on separate PCs, and you also say that one of them is also connected to a PIC.

My first thought is that on the XBee that’s connected both to a PC and a PIC, the PC and the PIC will be fighting for control of the DIN line. From what you then say, it sounds as though the PC is winning. Characters that it sends are getting through; characters that the PIC sends are being ignored.

Generally in digital electronics it doesn’t make sense to connect more than one output to a particular input. I say “generally” because there are cases like open-collector or tri-state logic where it makes perfect sense. However, this doesn’t sound like one of those cases.

What happens if you disconnect the PC from the XBee that’s also connected to the PIC?