Example - Leica GR30 Online Help Manual

Appendix B: NMEA Messages
available and used for displacement computation, or 0, i.e. no observation is available and no displacement is computed at this epoch. If
the user configures a 1 Hz epoch rate NMEA LDM stream and the receiver positioning rate is 20 Hz, then for each epoch 20
observations are used for displacement calculation. In this case, the epoch to epoch data completeness ratio can be equal to 1, i.e. all
20 observations are available and used for displacement computation, or 0, i.e. no observations are available and no displacement is
computed at this epoch, or any value between 0 and 1, e.g. 0.2, i.e. 4 observations out of 20 possible are used for displacement
computation.
Overall data completeness ratio is reset after changing the reference position or enabling/disabling the Velocity & Displacement
[3]
Engine.

Example

User defined Talker ID = GN
$GNLDM,113805.50,030215,113805.50,030215,0.0101,0.0204,0.0459,0.0021,0.0020,0.0041,0.00021,0.00023,0.00041,0.05,19,0,1,1*4
7
259