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•
Grid: frequency hopping grid step size:
0x00: 25.390625kHz for FCC use case
0x01: 3.90625kHz for non-FCC use case
•
Hopping: configures intra-packet hopping:
0x00: no hopping (test purpose)
0x01: hopping
•
BW: bandwidth occupied by the frequency hopping pattern:
0x00: 39.06kHz
0x01: 85.94kHz
0x02: 136.72kHz
0x03: 183.59kHz
0x04: 335.94kHz
0x05: 386.72kHz
0x06: 722.66kHz
0x07: 773.44kHz
0x08: 1523.4kHz
0x09: 1574.2kHz
Other values are RFU
•
Hop sequence: 9-bit integer, seed of the pseudo-random frequency hopping sequence:
value in [0; 383] for Grid=0x00, BW in {0x06, 0x07, 0x08, 0x09}
value in [0; 383] for Grid=0x01, BW in {0x00, 0x01, 0x02, 0x03}
value in [0; 511] for Grid=0x01, BW in {0x04, 0x05, 0x06, 0x07, 0x08, 0x09}
•
DeviceOffset: per device frequency offset to reduce the risk of packet collision. Frequency offset (Hz) = DeviceOffset *
488.28125Hz:
signed value in [-26; 25] for Grid = 25.390625kHz
signed values in [-4; 3] for Grid= 3.90625kHz
For a FCC use case, DeviceOffset shall not be changed once configured.
•
Payload: actual payload to encode. Returns CMD_OK if the parameters are valid and if the payload can be encoded,
CMD_PERR otherwise.
The maximum supported packet length is 255 coded bytes. The maximum user payload length is given by the
Maximum user payload length, in
Table 8-24: Maximum user payload length, in bytes
CR
CR=5/6
CR=2/3
CR=1/2
CR=1/3
A FCC use case corresponds to a use case where BW = 0x08/0x09, Hopping = 0x01, Grid = 0x00.
Note: This command does not send the LR-FHSS packet. The transmission will be triggered using SetTx(...) command.
LR1121
User Manual
Rev 1.1
UM.LR1121.W.APP
Mar 2023
bytes.
HeaderCount=1
HeaderCount=2
189
151
112
74
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HeaderCount=3
178
167
142
133
105
99
69
65
Table 8-24:
HeaderCount=4
155
123
92
60
81 of 130
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