L3 comminications SERIES 5000, Operation And Maintenance Manual

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C-16
APPENDIX C TPU Software Interface and Control
Series 5000 Sonar System Operations and Maintenance Manual P/N 11210060, Rev. 13.0
6:
TPU watchdog. If this bit is set then a task may be locked.
The TPU uses multi-threaded OS technology where
multiple tasks are performed simultaneously. These tasks
include acquiring the data, formatting it, parsing the sensor
messages, handling navigation input, etc. A software error
can cause a thread to cease execution although this is
extremely rare. Whilst the sonar can continue operating if a
non-critical thread is stopped certain critical threads will
render the sonar inoperable if they are stopped. If this flag is
raised then one or more threads has ceased. It is
recommended to shutdown the system and reboot.
7:
Reserved.
An example status message:
$PKLA,ST,RS2WF1RM0SM0DM0TP7VF0RC1SD0HD57ER24*hh<CR><LF>
C.5.2 Heartbeat Message
Once per ping (or less, see HB command) a heartbeat message is output. This
message contains the current ping number, time, altitude and the current error
status as follows:
$PKLA,HB,PxxxxHddMddSddTdddAdd.dEyy*hh<CR><LF>
Following the "HB" the fields are ping number, hours, minutes, seconds,
thousandths of seconds, altitude in meters and error state.
C.5.3 Sensor Message
Roughly once per second (if enabled, see Startup Script and Remote Control
above) a sensor message is output. This message contains the data from the
onboard sensors and the current time. The format of this message is:
$PKLA,SI,HddMddSddTdddCddd.dPdd.dRdd.dDd.ddd*hh<CR><LF>
where the fields are hours, minutes, seconds, thousandths of seconds, heading,
pitch, roll and depth. The depth field is in volts. A full scale reading of 5.0 volts
corresponds to full scale from the pressure sensor. The full scale of the sensor must
be used to convert this value to depth. The sensor measures absolute pressure so
the atmospheric pressure must also be taken into account (14.7 psi). An example of
the calculation is:
depth = ((Volts * Full_Scale / 5.0) – 14.7) / 1.458 meters
where Volts is the value in the depth field of the sensor message and Full_Scale is
the full scale output of sensor in psi.