Spectra Precision ProMark 800 Reference Manual - Manual (Page 402)

390
Output Message Library
The GPS broadcast ionosphere model (Klobuchar) is used.
Reminder on How
to Output ION
Messages
Use the $PASHS,RAW command with the syntax below:
$PASHS,RAW,ION,,ON,
For more details on the $PASHS,RAW command, refer to the
Set Command Library Chapter.
As an example, the command below will output ION
messages on port A at a rate of 5 seconds:
$PASHS,RAW,ION,A,ON,5
MPC: GNSS Measurements
This message contains the GPS/GLONASS/SBAS L1 C/A, L2P
data of one satellite for one epoch.
The message is as follows:
$PASHR,MPC,
The message’s binary structure is described in the table
below.
Unsigned
short Check-
sum
2
The checksum is computed by breaking the struc-
ture into 37 unsigned shorts, adding them together,
and taking the least significant 16 bits of the result.
Total 76
Type Name Size Contents
Type Size Contents
Unsigned short 2
Sequence tag (unit: 50 ms) modulo 30 minutes. See
NOTE 1 below.
Unsigned char 1
Number of remaining structure to be sent for current
epoch
Unsigned char 1
Satellite index number
GPS: 1-32
SBAS: 33-51
GLONASS: 65-88
Unsigned char 1 Satellite elevation angle (degree)
Unsigned char 1 Satellite azimuth angle (2-degree increments)
Unsigned char 1 Channel ID not duplicated for the current epoch
29 C/A code data block (29 bytes)