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RF65
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ADVANCED COMMUNICATIONS & SENSING
DATASHEET
5.5. Packet Mode
5.5.1. General Description
In Packet mode the NRZ data from the demodulator is not directly accessed by the uC but stored in the FIFO and
accessed via the SPI interface.
In addition, the RF65 packet handler performs several packet oriented tasks such as Preamble and Sync word check,
CRC check, dewhitening of data, Manchester decoding, address filtering, AES decryption, etc. This simplifies software and
reduces uC overhead by performing these repetitive tasks within the RF chip itself.
Another important feature is ability to empty the FIFO in Sleep/Stdby mode, ensuring optimum power consumption and
adding more flexibility for the software.
CONTROL
DIO0
DIO1
DIO2
DIO3
DIO4
DIO5
Data
Rx
SYNC
RECOG.
PACKET
HANDLER
FIFO
(+SR)
SPI
NSS
SCK
MOSI
MISO
Figure 27. Packet Mode Conceptual View
Note
The Bit Synchronizer is automatically enabled in Packet mode.
5.5.2. Packet Format
5.5.2.1. Fixed Length Packet Format
Fixed length packet format is selected when bit
PacketFormat
is set to 0 and
PayloadLength
is set to any value greater
than 0.
In applications where the packet length is fixed in advance, this mode of operation may be of interest to minimize RF
overhead (no length byte field is required). All nodes should be programmed with the same packet length value.