Specifications

VP ONCORE COMMAND REFERENCE
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8 CHANNEL POSITION/STATUS/DATA
MESSAGE (@@Ea)
This input command sets the rate that the 8 Channel
Position/Status/Data information in the response message is output. The
mode parameter (m) in the input message instructs the GPS receiver to
either output this message one time (polled), or to output this message at
the indicated update rate (continuously). Once the GPS receiver is set to
continuous output, the continuous message flow can be stopped by
sending a onetime output request. The GPS receiver will output the
message one more time, then terminate any further message outputs. If
the VP has been commanded into Idle mode, it outputs the last known
valid 8 Channel Position/Status/Data message once when polled.
The state of the rate byte is stored in non-volatile memory. If the GPS
receiver was continuously outputting the position/status/data output
when turned off it will begin to output this message continuously (at the
selected update rate) again when the main power is reapplied.
The 8 Channel Position/Status/Data output is explained in the response
message section. Refer to commands for more details on the formats of
these parameters.
The number of satellites visible is computed using the current date, time,
position, almanac, and a default mask angle of ten degrees. If a current
almanac is unavailable, the number of reported visible satellites will be
zero. This condition will not prevent satellites from being tracked.
In order for a satellite to be used for positioning, the satellite mode must
reach eight, indicating that the ephemeris for that satellite has been
acquired. Once the ephemeris is available, the satellite can be used for
positioning in modes five through eight.
NOTE: United States export laws prohibit GPS receivers from
outputting valid data if the altitude is greater than 18,000 meters and the
velocity is greater than 514 meters per second. If the GPS receiver is
used above both these limits, the height and velocity outputs are
clamped to the maximum values. In addition, the latitude and longitude
data will be incorrect.
Default mode: Polled
124 Synergy Systems, LLC 05OCT01