RF64 Datasheet, PDF (49/76 Pages) List of Unclassifed Manufacturers – ADVANCED COMMUNICATIONS & SENSING

ADVANCED COMMUNICATIONS & SENSING
RF64
5.5. Packet Mode
5.5.1. General Description
Similar to Buffered mode operation, in Packet mode the NRZ data to (from) the (de)modulator is not directly
accessed by the uC but stored in the FIFO and accessed via the SPI Data interface.
In addition, the RF64‟s packet handler performs several packet oriented tasks such as Preamble and Sync word
generation, CRC calculation/check, whitening/dewhitening of data, address filtering, etc. This simplifies still further
software and reduces uC overhead by performing these repetitive tasks within the RF chip itself.
Another important feature is ability to fill and empty the FIFO in Stby mode, ensuring optimum power consumption
and adding more flexibility for the software.
RF64
CONTROL
IRQ_0
IRQ_1
Data
Rx
SYNC
RECOG.
Tx
PACKET
HANDLER
FIFO
(+SR)
SPI
CONFIG
DATA
NSS_CONFIG
NSS_DATA
SCK
MOSI
MISO
Datapath
Figure 42: Packet Mode Conceptual View
Note that Bit Synchronizer and Sync word recognition are automatically enabled in Packet mode.
5.5.2. Packet Format
Two types of packet formats are supported: fixed length and variable length, selectable by the
PKTParam_Pkt_format bit. The maximum size of the payload is limited by the size of the FIFO selected (16, 32, 48
or 64 bytes).
5.5.2.1. Fixed Length Packet Format
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, whether Tx only, Rx only, or Tx/Rx should be
programmed with the same packet length value.
The length of the payload is set by the PKTParam_Payload_length register and is limited by the size of the FIFO
selected.
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