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D

Logs summary

186

 MiLLennium GPSCard Software Version 4.50 Command Descriptions Manual Rev 1

Almanac and health data are contained in subframes four and five of the satellite broadcast message. Subframe four
contains information for SVs 25-32, as well as ionospheric, 

UTC

 and 

SV

 configuration data. Subframe five contains

information for 

SVS

 1-24.

Subframes four and five each contain 25 pages of data, and each page contains ten 30-bit words of information as
transmitted from the satellite. The 

RALA

/

B

 log outputs this information with parity bits checked and removed (ten

words - 24 bits each). The log will not be generated unless all ten words pass parity.

This log will alternately report each page from subframes four and five as they are collected. Logging this log
onnew would be the optimal logging rate to capture data from pages in subframes four and five as they are received.

RALA

 logs contain a hex representation of the raw almanac data (one of the possible 25 pages of either subframe 4

or 5). 

RALB

 contains the raw binary information.

$RALA,7,16,8B0A54852C964C661F086366FDBE00A10D53DA6565F2503DD7C2AACBFED3
*05[CR][LF]

Format:

Message ID = 15

Message byte count = 52

$RALA

chan #

prn

subframe

*xx

[CR][LF]

1

$RALA

Log header

$RALA

2

chan #

Channel number collecting almanac data (0-11)

7

3

prn

PRN of satellite from which data originated

16

4

subframe

Subframe 4 or 5 of almanac data 
(60 hex characters)

8B0A54852C964C661F086366FDBE00A 
10D53DA6565F2503DD7C2AACBFED3

5

*xx

Checksum

*05

6

[CR][LF]

Sentence terminator

[CR][LF]

1

Sync

3

char

0

(header)

Checksum

1

char

3

Message ID

4

integer

4

Message byte count

4

integer

8

2

Channel number, 0-11

4

integer

12

3

PRN number, 1-32

4

integer

16

4

Almanac data, data [30]

30

char

20

5

Filler bytes

2

char

50