Semtech LR1110 - LR1110 GNSS Almanac Data

LR1110
User Manual Rev.1.0
UM.LR1110.W.APP March 2020
102 of 130
Semtech
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11.4.6 GnssGetConsumption
The command GnssGetConsumption( ) allows to read out the duration of the Radio capture and the CPU processing phases
of the GNSS Scanning capture. These timings are expressed in microseconds.
This can be used in order to determine the GNSS Scanning power consumption.
11.5 GNSS Almanac
The GNSS Almanac consist in information about the state of the entire GNSS satellite constellation and coarse data on every
satellite's orbit. There is a specific almanac for each constellation. The almanac data is valid for up to 90 days.
The use of the almanac allow to significantly optimize the GNSS scanning duration: it allows the LR1110 to search only for
visible satellites given the user location and time, and therefore allows to reduce the energy required for a GNSS scanning.
The Alamanac is used by the LR1110 in the GNSS assisted mode.
The LR1110 is pre-programmed with the latest Almanac data at the date of the production test. Even if the Almanac data is
valid for 90 days, it is advised to use the latest Almanac data for power optimization. The up-to-date almanac is Available
from the Device Management Center (DMC) server.
The whole Almanac data can be updated (full update). The Almanac is entirely stored in the flash memory, therefore kept
after power off or Sleep mode without retention.
Table 11-14: GnssGetConsumption Command
Byte 0 1
Data from Host 0x04 0x19
Data to Host Stat1 Stat2
Table 11-15: GnssGetConsumption Response
Byte 0 1 2 3 4 5 6 7 8
Data from
Host
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
Data to
Host
Stat1
CPU
Time
(31:24)
CPU
Time
(23:16)
CPU
Time
(15:8)
CPU
Time
(7:0)
Radio
Time
(31:24)
Radio
Time
(23:16)
Radio
Time
(15:8)
Radio
Time
(7:0)