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SX1231J
WIRELESS & SENSING
DATASHEET
Rev 2 - April 2012
RegOokPeak
(0x1B)
7-6 OokThreshType rw 01 Selects type of threshold in the OOK data slicer:
00 Æ fixed 10 Æ average
01 Æ peak 11 Æ reserved
5-3 OokPeakTheshStep rw 000 Size of each decrement of the RSSI threshold in the OOK
demodulator:
000 Æ 0.5 dB 001 Æ 1.0 dB
010 Æ 1.5 dB 011 Æ 2.0 dB
100 Æ 3.0 dB 101 Æ 4.0 dB
110 Æ 5.0 dB 111 Æ 6.0 dB
2-0 OokPeakThreshDec rw 000 Period of decrement of the RSSI threshold in the OOK
demodulator:
000 Æ once per chip 001 Æ once every 2 chips
010 Æ once every 4 chips 011 Æ once every 8 chips
100 Æ twice in each chip 101 Æ 4 times in each chip
110 Æ 8 times in each chip 111 Æ 16 times in each chip
RegOokAvg
(0x1C)
7-6 OokAverageThreshFilt rw 10 Filter coefficients in average mode of the OOK
demodulator:
00 Æ f
C
≈ chip rate / 32.π 01 Æ f
C
≈ chip rate / 8.π
10 Æ f
C
≈ chip rate / 4.π 11 Æf
C
≈ chip rate / 2.π
5-0 - r 000000 unused
RegOokFix
(0x1D)
7-0 OokFixedThresh rw 0110
(6dB)
Fixed threshold value (in dB) in the OOK demodulator.
Used when OokThresType = 00
RegAfcFei
(0x1E)
7 - r 0 unused
6 FeiDone r 0 0 Æ FEI is on-going
1 Æ FEI finished
5 FeiStart w 0 Triggers a FEI measurement when set. Always reads 0.
4 AfcDone r 1 0 Æ AFC is on-going
1 Æ AFC has finished
3 AfcAutoclearOn rw 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
2 AfcAutoOn rw 0 0 Æ AFC is performed each time AfcStart is set
1 Æ AFC is performed each time Rx mode is entered
1 AfcClear w 0 Clears the AfcValue if set in Rx mode. Always reads 0
0 AfcStart w 0 Triggers an AFC when set. Always reads 0.
RegAfcMsb
(0x1F)
7-0 AfcValue(15:8) r 0x00 MSB of the AfcValue, 2’s complement format
RegAfcLsb
(0x20)
7-0 AfcValue(7:0) r 0x00 LSB of the AfcValue, 2’s complement format
Frequency correction = AfcValue x Fstep
RegFeiMsb
(0x21)
7-0 FeiValue(15:8) r - MSB of the measured frequency offset, 2’s complement
RegFeiLsb
(0x22)
7-0 FeiValue(7:0) r - LSB of the measured frequency offset, 2’s complement
Frequency error = FeiValue x Fstep
RegRssiConfig
(0x23)
7-2 - r 000000 unused
1 RssiDone r 1 0 Æ RSSI is on-going
1 Æ RSSI sampling is finished, result available
0 RssiStart w 0 Trigger a RSSI measurement when set. Always reads 0.
RegRssiValue
(0x24)
7-0 RssiValue r 0xFF Absolute value of the RSSI in dBm, 0.5dB steps.
RSSI = -RssiValue/2 [dBm]
