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CONFIGURATION REGISTER 5 ADDRESS (0Ah) R/W TX SIGNAL FIELD
Bits 7:4
R/W but not currently used internally, should be set to zero to ensure compatibility with future revisions.
Bits 3
Select preamble mode
0 = Normal, long preamble interoperable with 1 and 2Mbps legacy equipment
1= short preamble and header mode (optional in 802.11)
Bit 2
Reserved, must be set to 0
Bits 1:0
TX data Rate. Must be set at least 2
μ
s before needed in TX frame. This selects TX signal field code from the registers above.
00 = DBPSK - 11 chip sequence (1Mbps)
01 = DQPSK - 11 chip sequence (2Mbps)
10 = CCK - 8 chip sequence (5.5Mbps)
11 = CCK - 8 chip sequence (11Mbps)
CONFIGURATION REGISTER 6 ADDRESS (0Ch) R/W TX SERVICE FIELD
Bits 7:0
R/W but not currently used internally. Bit 7 may be employed by the MAC in 802.11 situations to resolve an ambiguity in the
length field when in the 11Mbps mode. Bit 2 should be set to a 1 where the reference oscillator of the radio is common for both
the carrier frequency and the data clock. All other bits should be set to 0 to insure compatibility.
CONFIGURATION REGISTER 7 ADDRESS (0Eh) R/W TX LENGTH FIELD (HIGH)
Bits 7:0
This 8-bit register contains the higher byte (bits 8-15) of the transmit Length Field described in the Header. This byte combined
with the lower byte indicates the number of microseconds the data packet will take.
CONFIGURATION REGISTER 8 ADDRESS (10h) R/W TX LENGTH FIELD (LOW)
Bits 7:0
This 8-bit register contains the lower byte (bits 0-7) of the transmit Length Field described in the Header. This byte combined
with the higher byte indicates the number of microseconds the data packet will take.
CONFIGURATION REGISTER 9 ADDRESS (12h) R/W TX CONFIGURE
Bit 7
CCA sample mode time
0 = 19.9
μ
s
1 = 15.8
μ
s
Bits 6:5
CCA mode
00 - CCA is based only on ED
01 - CCA is based on (CS1 OR SQ1/CS2)
10 - CCA is based on (ED AND (CS1 OR SQ1/CS2))
11 - CCA is based on (ED OR (CS1 | SQ1/CS2))
Bit 4
TX test modes
0 = Alternating bits for carrier suppression test. (Needs scrambler off (CR32 <2> = 1)).
1 = all chips set to 1 for CW carrier. This allows frequency measurement
Bit 3
Enable TX test modes
0 = normal operation
1 = Invoke tests described by bit 4
Bit 2
Antenna choice for TX
0 = Set AntSel low
1 = Set AntSel high
Bit:1
TX Antenna Mode
0 = set AntSel pin to value in bit 2
1 = set AntSel pin to antenna for which last valid header CRC occurred
Bit 0
R/W but not currently used internally, should be set to zero to ensure compatibility with future revisions.
CONFIGURATION REGISTER 10 ADDRESS (14h) R/W RX CONFIGURE
Bit 7
Initial CS2 estimate
0 = Use dot product result
1 = Use SQ1 from Barker correlator peaks
see CR30 and CR48 for related thresholds
Bit 6
CIR estimate/ Dot product clock control.
0 = on during acquisition
1 = only on after detect.
HFA3861A