SX1231
ADVANCED COMMUNICATIONS & SENSING
DATASHEET
7
6
-
r
r
0
0
unused
RegAfcFei
(0x1E)
FeiDone
0 Æ FEI is on-going
1 Æ FEI finished
5
4
FeiStart
w
r
0
1
Triggers a FEI measurement when set. Always reads 0.
AfcDone
0 Æ AFC is on-going
1 Æ AFC has finished
3
2
AfcAutoclearOn
AfcAutoOn
rw
rw
0
0
Only valid if AfcAutoOn is set
0 Æ AFC register is not cleared before a new AFC phase
1 Æ AFC register is cleared before a new AFC phase
0 Æ AFC is performed each time AfcStart is set
1 Æ AFC is performed each time Rx mode is entered
1
0
AfcClear
AfcStart
w
w
0
0
Clears the AfcValue when set. Always reads 0
Triggers an AFC when set. Always reads 0.
7-0 AfcValue(15:8)
7-0 AfcValue(7:0)
7-0 FeiValue(15:8)
7-0 FeiValue(7:0)
rw
0x00 MSB of the AfcValue, 2’s complement format
RegAfcMsb
(0x1F)
rw
r
0x00 LSB of the AfcValue, 2’s complement format
RegAfcLsb
(0x20)
Frequency correction = AfcValue x Fstep
-
-
MSB of the measured frequency offset, 2’s complement
RegFeiMsb
(0x21)
r
LSB of the measured frequency offset, 2’s complement
RegFeiLsb
(0x22)
Frequency error = FeiValue x Fstep
7-4
3
-
r
0000 unused
RegRssiConfig
(0x23)
FastRx
rw
0
Fast or standard Rx wakeup sequence
0 Æ 2 RSSI samples over RssiThreshold are required to
start the receiver
1 Æ 1 RSSI sample over RssiThreshold is enough to start
the receiver
2
1
-
r
r
0
1
unused
RssiDone
0 Æ RSSI is on-going
1 Æ RSSI sampling is finished, result available
0
RssiStart
w
r
0
Trigger a RSSI measurement when set. Always reads 0.
7-0 RssiValue
0xFF Absolute value of the RSSI in dBm, 0.5dB steps.
RegRssiValue
(0x24)
RSSI = -RssiValue/2 [dBm]
Rev 2 - Nov 2009
Page 66
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