Specifications

BATS AND PORTABLE BATS OPERATION
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3.3.4 USBL MENU
Pertains to functions/parameter settings on the BATS Transceiver.
USBL  GPS/Time Sync
From the USBL main menu select GPS/Time Sync to bring up the USBL GPS/Time Sync setup pa-
rameter dialog box.
Comport#1 on the BATS Transceiver
is reserved for the GPS time. By click-
ing on the “Port Settings” button an-
other dialog appears in which to set
the comport specific parameters.
Select either the ZDA format or the
GGA format.
When ZDA or GGA is selected the Time coming
from the SPC packet is ignored so that it does not
update from the PC. “Time” on the Transceiver is
synchronized with the GPS time. The Transceiver
synchronizes all sensor data and target detection
to this time. For example, when the target reply is
detected the raw data is automatically time-
stamped to within 50ms of the GPS time. The same for all the analog sensor data and the compass
serial port data.
Example of ZDA sentence.
$--ZDA,hhmmss.ss,xx,xx,xxxx, xx,xx*hh
Example of GGA sentence.
$GPGGA,174007,4131.4511,N,07040.3336,W,1,6,01.0,000003.1,M, -00033.7,M*hh
All serial sensor data into the USBL or Trackman interface is time tagged and the closest point to
the reply detection is used for motion compensation.