DR + GPS
STARTER KIT REFERENCE MANUAL
Lassen DR + GPS Reference Manual 104
0x28-14: GPS Ionospheric Model and UTC Parameters Initialization
The elements of the ionosphere / UTC message match subframe 4, page 18 as
downlinked by the satellite. TLM words, HOW words and parity bits are omitted.
The data in this message may change after initialization through data decode. A
10-bit Week Number of Collection is added as a time tag.
If the information is unknown, all data fields are zero. To erase ionosphere and
UTC model information in the DR GPS module, set this data with source byte
equal to zero (Invalid / Clear).
Table 79: 0x28-14: GPS Ionospheric Fixed Point Model Report
Byte Name Type Units/LSB Range /
Value Meaning
Code U8 0x28
Subcode U8 0x14 Iono/UTC Model
0 0-2 Source U3 0
1
2
3
Invalid / Clear
Host Input
Host Override
Data Decode
0 3 Newness U1 0
1
From BBRAM
New
0 6-7 GPS Week Extension U2 2 MSBs of Week
1 Week of collection U8 8 LSBs of Week
2-25 Compressed Iono / UTC 24xU8
0x28-16: Ephemeris Initialization
The elements of the ephemeris message match the three subframes that are
downlinked by the satellite. TLM words, HOW words and parity bits are omitted.
The data in this message may change after initialization through data decode. A
10-bit Week Number of Applicability is included in the compressed data.
If the information is unknown, all data fields are zero. To erase ephemeris
information in the DR GPS module, set this data with source byte equal to zero
(Invalid / Clear).