DR + GPS
STARTER KIT REFERENCE MANUAL
Lassen DR + GPS Reference Manual 103
0x28-13: Almanac Health Initialization
The elements of the almanac health message match subframe 4 and 5, page 25
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. An 8-bit Week Number of Applicability is included in the compressed
data, and two extra bits are given in Byte 0 to extend this to a full GPS week
number.
If the information is unknown, all data fields are zero. To erase almanac health
information in the DR GPS module, set this data with source byte equal to zero
(Invalid / Clear).
Table 78: 0x28-13: Compressed Almanac Health Report Message
Byte Name Type Units/
LSB Range /
Value Meaning
Code U8 0x28
Subcode U8 0x13 Almanac Health Page
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 WNoa
1 WNoa U8 IDC-200C
2-25 Compressed Health & A-S 24xU8 Subframe 4 Page 25
26-49 Compressed Health 24xU8 Subframe 5 Page 25