CC2510FX Datasheet, PDF (199/253 Pages) List of Unclassifed Manufacturers – True System-on-Chip with Low Power RF Transceiver and 8051 MCU

CC2510Fx / CC2511Fx
Bit Field name Description
7
CRC_OK
1: CRC for received data OK (or
CRC disabled)
0: CRC error in received data
6:0 LQI
The Link Quality Indicator
estimates how easily a received
signal can be demodulated
Table 60: Received packet status byte 2
(second byte appended after the data)
Note that register fields that control the
packet handling features should only be
altered when CC2510Fx/CC2511Fx is in the
IDLE state.
15.8.1 Data whitening
From a radio perspective, the ideal over
the air data are random and DC free. This
results in the smoothest power distribution
over the occupied bandwidth. This also
gives the control loops in the receiver
uniform operation conditions (no data
dependencies).
Real world data often contain long
sequences of zeros and ones.
Performance can then be improved by
whitening the data before transmitting, and
de-whitening in the receiver. With
CC2510Fx/CC2511Fx, this can be done
automatically
by
setting
PKTCTRL0.WHITE_DATA=1. All data,
except the preamble and the sync word,
are then XOR-ed with a 9-bit pseudo-
random (PN9) sequence before being
transmitted.
At the receiver end, the data are XOR-ed
with the same pseudo-random sequence.
This way, the whitening is reversed, and
the original data appear in the receiver.
Setting PKTCTRL0.WHITE_DATA=1 is
recommended for all uses, except when
over-the-air compatibility with other
systems is needed.
15.8.2 Packet format
The format of the data packet can be
configured and consists of the following
items:
• Preamble
• Synchronization word
• Length byte or constant
programmable packet length
• Optional Address byte
• Payload
• Optional 2 byte CRC
Preamble bits
(1010...1010)
Optional data whitening
Optionally FEC encoded/decoded
Optional CRC-16 calculation
Data field
8 x n bits
16/32 bits
8
bits
8
bits
8 x n bits
16 bits
Figure 46: Packet Format
Legend:
Inserted automatically in TX,
processed and removed in RX.
Optional user-provided fields processed in TX,
processed but not removed in RX.
Unprocessed user data (apart from FEC
and/or whitening)
CC2510Fx/CC2511Fx PRELIMINARY Data Sheet (Rev. 1.2) SWRS055A Page 199 of
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