Specifications

VP ONCORE COMMAND REFERENCE
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6 CHANNEL TIME RAIM SETUP AND STATUS
MESSAGE (@@Bn)
NOTE: The input/output messages described here are available only if
VP receiver option ‘I’ is installed.
The Motorola VP receiver uses the Time RAIM algorithm to exploit
redundancy in the GPS time solution in order to detect and isolate faulty
satellites. The Time RAIM Setup and Status Message allows the user to
change the update rate, the configuration for the 1PPS output, and the
Time RAIM alarm limit.
The rate parameter instructs the GPS receiver to either output this
message one-time (polled), or to output this message at the indicated
update rate (continuously). If the message rate is the same as the 1PPS
rate, then the message and the 1PPS pulse are synchronized. Once the
GPS receiver is set to continuous output, the continuous message flow
can be stopped by sending a one-time output request. The GPS receiver
will output the message one more time, then terminate any further
message outputs. The state of the rate parameter is stored in nonvolatile
memory If the GPS receiver was continuously outputting the message
when turned off, it will begin to output this message continuously (at the
selected rate) again when power is reapplied. If the VP has its Idle Mode
option enabled, the rate parameter selection is unavailable, and the GPS
receiver outputs the last valid message once when polled.
The state of the rate byte is stored in RAM. If the GPS receiver was
continuously outputting the message when turned off and backup power
is applied, then it will begin to output this message continuously (at the
selected update rate) again when the main power is reapplied. If backup
power is not applied during power down, then the GPS receiver will start
up with a default rate of zero. The other Time RAIM control parameters
are also stored in RAM, so they will be reset to their default values if
backup power is not applied during power down.
The pulse generation can be controlled with the 1PPS control mode byte.
The pulse can be on all the time, off all the time, on only when the
receiver is tracking at least one satellite, or on only when the time
solution is within the alarm threshold. The number of satellites appearing
in the table below are the minimum which must be tracked to ensure the
detection, isolation, and removal of faulty satellites. The probability of
detection and isolation of a faulty satellite is greater.
102 Synergy Systems, LLC 05OCT01