- The micro-controller is programmed to send a character “Y” continuously with required settings
as 9600bps, No flow control, 8 data bits, parity none and 1 stop bit. This is compatible with
Zigbee modem’s default settings.
- Micro-controller TxD pin is connected to DIN pin of the modem1 whereas the RxD pin of
connected to DOUT pin.
- As soon as the uC is turned ON the Tx LED of modem 1 starts blinking. It indicates transmission of
- Modem 2 is connected to COM port of the PC and hyper terminal is opened.
- Problem here is, Modem 2 does not receive any data because neither RX LED glows nor data is
received on hyper terminal.
· If uC is directly connected to PC, “Y” is printed on hyper terminal continuously.
Possible reasons of the failures are listed below:
· By default modem is in “unicast” mode. So (SL, SH) and (DL, DH) are needed to be configured.
An X-CTU software shows “MY” is read only where as Manual says its Read/Set parameter . So
16 bit addressing cannot be configured.
· Though 64 bit addressing is configured, there is no communication between modems. Modem 1’s
(DL, DH) are (SL, SH) of modem 2 and vice versa.
· In order for modules to communicate with each other, the modules must share the same channel
number. The channel is one of three addressing options available to the module. The other
options are the PAN ID (ID command) and destination addresses (DL & DH commands).
These are line from manual of Xbee.
When checked “CH” parameter in the firmware modem1 shows 10 and modem two shows 12.
Other things like Pan ID and addressing are done as required.