Document MT0605P.E
© Xsens Technologies B.V.
MTi User Manual
47
4.12 Timestamp and packet counter output
Each data message can be accompanied by a packet counter and/or timestamp.
4.12.1 Packet counter
The packet counter is an incremental number that comes with each packet, regardless of what data is
in the packet. It can also mean that time differences between packet counters may not be the same.
Note that the packet counter is a good indication if data is missed during transmission of the data, as
the packet counters are created when generating (composing) a data message prior to sending.
4.12.2 Time UTC
Time UTC is time in the format of UTC; note that this time does not have to be synchronized with GPS
UTC. The format is described below:
DATA (B)
Description
0
Nanoseconds of second, range 0 .. 1.000.000.000
4
Year, range 1999 .. 2099
6
Month, range 1..12
7
Day of Month, range 1..31
8
Hour of Day, range 0..23
9
Minute of Hour, range 0..59
10
Seconds of Minute, range 0..59
11
0x01 = Valid Time of Week
0x02 = Valid Week Number
0x04 = Valid UTC
When outputted, the Time UTC starts as following:
-
At 0.0 sec, unless
-
A time is available in the non-volatile memory, unless
-
GPS time is available (MTi-G-700 only)
When the time stamp wraps over 0.00h (midnight), the date progresses a day.
4.12.3 Time stamp (Sample Time Fine)
The time stamp is a 0.1 ms resolution 4 byte time stamp.
4.12.4 Setting UTC time on non-
GPS MTi’s
It is possible to set a time in UTC format to an MTi. The MTi will count from this time using the internal
clock. As the moment of setting the time is different than the time the MTi receives the message and
sets the starting point, a message is implemented to adjust Time UTC in ticks of 0.1 ms. See [LLCP]
for more information about the messages SetUTCTime and AdjustUTCTime.