G)Fsk Commands; Setmodulationparam; Figure 8-6: (G)Fsk Whitening; Table 8-17: Setmodulationparam Command - Semtech LR1110 User Manual

The whitening is based around the 9-bit LFSR polynomial x^9+x^5+1. With this structure, the LSB at the output of the LFSR
is XORed with the MSB of the data.
At the initial stage, the command SetGfskWhitParams( ) allows setting the whitening Seed.
8.4.3.5 CRC
The LR1110 offers full flexibility to select the CRC polynomial and initial value of the selected polynomial. In addition, the
user can also select a complete inversion of the computed CRC to comply with some international standards.
The CRC can be enabled and configured by using the CrcType field in the command SetPacketParam( ). This field allows the
user to enable and select the length and configuration of the CRC.
The command SetGfskCrcParams( ) allows configuring the CRC polynomial and initial value.

8.5 (G)FSK Commands

8.5.1 SetModulationParam

The command SetModulationParam( ) allows to configure the modulation parameters for the selected modem. Since the
parameters are modem dependent, the description hereafter is valid only for the (G)FSK modem.

Table 8-17: SetModulationParam Command

Byte 0
Data from Host 0x02
Data to Host Stat1
LR1110
User Manual Rev.1.0
UM.LR1110.W.APP March 2020

Figure 8-6: (G)FSK Whitening

1 2 3
Bitrate Bitrate
0x0F
(31:24) (23:16)
Irq Irq
Stat2
Status Status
(31:24) (23:16)
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4 5 6
Bitrate Bitrate Pulse
(15:8) (7:0) Shape
Irq Irq
0x00
Status Status
(15:8) (7:0)
7 8 9
Fdev Fdev
BWF
(31:24) (23:16)
0x00 0x00 0x00
10 11
Fdev Fdev
(15:8) (7:0)
0x00 0x00
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