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

LR1110
User Manual Rev.1.0
UM.LR1110.W.APP March 2020
62 of 130
Semtech
www.semtech.com
Figure 8-6: (G)FSK Whitening
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 1 2 3 4 5 6 7 8 9 10 11
Data from Host 0x02 0x0F
Bitrate
(31:24)
Bitrate
(23:16)
Bitrate
(15:8)
Bitrate
(7:0)
Pulse
Shape
BWF
Fdev
(31:24)
Fdev
(23:16)
Fdev
(15:8)
Fdev
(7:0)
Data to Host Stat1 Stat2
Irq
Status
(31:24)
Irq
Status
(23:16)
Irq
Status
(15:8)
Irq
Status
(7:0)
0x00 0x00 0x00 0x00 0x00 0x00