ashtech DG14, Reference Manual

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196 DG14 and DG16 Board & Sensor Reference Manual
The DG16 outputs this message in binary format on every recording interval (RCI) for locked
satellites with an elevation equal to or greater than the elevation mask (ELM), and only if the number
of locked satellites is equal to or greater than the minimum satellite mask (MSV).
$PASHQ,MBN,[c1]
This command queries for raw satellite measurement data contained in the Ashtech
Type 2 data structure.
c1 is the optional port designator for the response. If a port is not specified, the
receiver sends the response to the current port.
If the command is set without a period, the DG16 uses the period set by the
$PASHS,RCI command If the $PASHS,RCI command is issued after this message
period has been set, the period resets to the RCI setting.
$PASHR,MBN
This message is not output unless the receiver is tracking at least one satellite. The
MBN message contains measurement information for doppler, carrier phase, and
satellite transmit time, as well as satellite PRN number, signal strength, elevation,
and azimuth. A separate MBN message is output for each satellite being tracked.
The structure of the message is n the format:
$PASHR,MBN,<Astech type 2 data checksum>
Table 7.7 outlines the data string format.
Table 7.7. $PASHR,MBN Data String
Field Bytes Content
char [datatype] 1 Always = 1
char [count] 1 Number of measurement structures to follow after this one
char [svprn] 1 Satellite PRN number
char chnind 1 Channel (1 to 14) assigned to the satellite
long [lost_lock_ctr] 4 Continuous counts since satellite is locked. This number is
incremented about 500 times per second
char [polarity] 1 This number is either 0 or 5. 0 indicates that satellite is just
locked, and 5 indicates that the beginning of the first frame
has been found
char [goodbad] 1 This number is either 22 or 24. Twenty-two indicates the
satellite is not usable; twenty-four indicates the satellite is
usable for position computation.
char [warning] 1 Always zero
char [ireg] 1 Satellite signal strength