Sag: glonass almanac data, Reminder on how to output sal messages – Spectra Precision ProMark 800 Reference Manual User Manual

Page 409

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397

Output Message Library

Reminder on How

to Output SAL

Messages

Use the $PASHS,RAW command with the syntax below:

$PASHS,RAW,SAL,<port_ID>,ON,<Rate>

For more details on the $PASHS,RAW command, refer to the
Set Command Library Chapter.

As an example, the command below will output SAL
messages on port A at a rate of 15 seconds:

$PASHS,RAW,SAL,A,ON,15

SAG: GLONASS Almanac Data

This message contains almanac data for one GLONASS
satellite.

The message is as follows:

$PASHR,SAG,<structure>

The message’s binary structure is described in the table
below.

Float

Af1

4

Clock correction (sec/sec)

Short

wna

2

Almanac week number

Short

wn

2

GPS week number

Long

4

Seconds of GPS week

Unsigned
short

Check-
sum

2

The checksum is computed by breaking the
structure into 34 unsigned shorts, adding them
together, and taking the least significant 16 bits
of the result.

Total

70

Type

Name

Size

Contents

Type

Name

Size

Contents

Short

prn

2

Satellite number 1-24

Short

frq

2

Satellite GLONASS frequency number
[-7,…,6]

Short

health

2

Satellite health 0=bad, 1=good

Float

e

4

Eccentricity

Long

4

Reference day number (days in range 1 to
1461)

Float

4

Correction to inclination (semicircles)

Float

w0

4

Longitude of first ascending node (semicir-
cles)

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