User's Manual

Chapter Three Operation
Man_905UD_2.0.doc Page 23
Establishing a Communications Link
Master Unit Slave Unit
Listen to ensure channel is clear
If clear, transmit “connect”
message
Radio TX LED flashes
------------------->
Receives message
Radio RX LED flashes
Check system and destination
address
If OK, set DCD LED and
output
Radio RX LED flashes
<-------------------
If message OK, transmit back
an ACK message.
Radio TX LED flashes
Acknowledgment received okay
communication link established
Set DCD LED and output
Successful Communications
Source Module Destination Module
Serial data is received
Serial RX LED flashes
Listen to ensure channel is clear
If clear, transmit message
Radio TX LED flashes
------------------->
Receive message
Radio RX LED flashes
Check system and destination
address
If OK, check error-check
Radio RX LED flashes
<-------------------
If message okay, transmit
back an ACK message.
Radio TX LED flashes
Acknowledgment received okay -
communication complete
Serial data is output
Serial TX LED flashes