CC2520_11 Datasheet, PDF (124/133 Pages) Texas Instruments – 2.4 GHZ IEEE 802.15.4/ZIGBEE RF TRANSCEIVER

CC2520 DATASHEET
2.4 GHZ IEEE 802.15.4/ZIGBEE® RF TRANSCEIVER
SWRS068 – DECEMBER 2007
FREQEST, A 0x048, R 0x00, Estimated RF frequency offset.
Bit
Bit mnemonic
no.
7:0
FREQEST[7:0]
Reset
value
0x00
Mode
R
Description
Signed 2’s complement value. Contains an estimate of the
frequency offset between carrier and the receiver LO. The offset
frequency is FREQESTx7800 Hz. DEM_AVG_MODE controls when
this estimate is updated. If DEM_AVG_MODE = 0 it is updated until
sync is found. Then the frequency offset estimate is frozen until
the end of the received frame. If DEM_AVG_MODE = 1 it is updated
as long as the demodulator is enabled.
MDMTEST1, A 0x05B, R 0x08, Test register for modem
Bit
Bit mnemonic
no.
7:4
RESERVED
3
RESERVED
2
RFC_SNIFF_EN
1
MODULATION_MODE
0
RESERVED
Reset
value
0000
1
0
0
0
Mode
R0
R/W
R/W
R/W
R/W
Description
Read as zero
Do not write.
0 - Packet sniffer module disabled
1 - Packet sniffer module enabled. The received and transmitted
data can be observed on GPIO pins.
Set one of two RF modulation modes for RX / TX
0 - IEEE 802.15.4 compliant mode
1 - Reversed phase, non-IEEE compliant
Do not write.
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