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Modes of operation
9XTend-PKG-R RS-232/485 RF Modem User Guide
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Modes of operation
XTend RF Modems operate in five modes.
Idle mode
When not receiving or transmitting data, the RF modem is in Idle Mode. The modem shifts into the other modes of
operation under the following conditions:
•
Transmit Mode (Serial data is received in the DI Buffer)
•
Receive Mode (Valid RF data is received through the antenna)
•
Sleep Mode (Sleep Mode condition is met)
•
Command Mode (Command Mode Sequence is issued)
Transmit mode
When the first byte of serial data is received from the UART in the DI buffer, the modem attempts to shift to Transmit
Mode and initiate an RF connection with other modems. After transmission is complete, the modem returns to Idle
Mode.
RF transmission begins after either of the following criteria is met:
1. RB bytes have been received by the UART and are pending for RF transmission. Refer to the RB (Packetization
Threshold) Command.
2. At least one character has been received by the UART and is pending for RF transmission; and RO character times
of silence been observed on the UART. Refer to the RO (Packetization Timeout) Command.