Saw: sbas almanac data, Reminder on how to output saw messages – Spectra Precision ProFlex 800 Reference Manual User Manual

Page 695

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681

Data Output

SAW: SBAS Almanac Data

This message contains almanac data for one SBAS satellite.

The message is as follows:

$PASHR,SAW,<structure>

The message’s binary structure is described in the table

below.

Reminder on How

to Output SAW

Messages

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

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

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

Type

Name

Size

Contents

char Id

1

Data

ID

char

Health

1

Satellite Health&Status bitwise meaning is:
Bit0 – Ranging On(0), Off(1)
Bit1 – Corrections On(0), Off(1)
Bit2 – Broadcast Integrity On(0), Off(1)
Bit3 – Reserved
Bit4-7 – SBAS provider ID (0-15):
0 – WAAS,
1 – EGNOS,
2 – MSAS,
3-13 – Not assigned yet,
14-15 – Reserved

long

T0

4

Almanac data reference time within the day
expressed in the SBAS time scale (seconds)

float

3*4

Satellite ECEF X,Y,Z coordinates (meters)

float

3*4

Satellite ECEF velocity X’, Y’, Z’ coordinates
(m/s)

long

Tow

4

Time within week in GPS time scale when
SBAS almanac was received

char

Wn

1

Week number in GPS time scale modulo 256
when SBAS almanac was received

char

Prn

1

Satellite number (33 to 51)

Unsigned short

Check-
sum

2

The checksum is computed by breaking the
structure into 18 unsigned shorts, adding them
together, and taking the least significant 16
bits of the result.

Total

38

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