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9XCite‐PKG‐R™ RS‐232/485 RF Modem – Product Manual v2.1 [2007.01.04]
3.2.3. Receive Mode
If a modem detects RF transmitted data while operating in Idle Mode, it transitions into Receive
Mode to start receiving packets. Once a packet is received, it goes through the receiving-end of a
CRC (cyclic redundancy check) to ensure that the data was transmitted without error. If the CRC
data bits on the incoming packet are invalid, the packet is discarded. If the CRC is valid, the packet
is placed the DO Buffer. This process is shown in the figure below:
Figure 3‐05. Receive Mode Data Flow
The modem returns to Idle Mode after valid data is no longer detected or once an error is detected
in the received data. If serial data-to-transmit is stored in the DI buffer while the modem is giving
precedence to Receive Mode, the data will be transmitted after the modem finishes receiving data
and returns to Idle Mode.
© 2007 MaxStream, Inc.
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