NavCom Sapphire Rev.J - Manual (Page 301)

Sapphire Technical Reference Manual Rev. J
301
2.57 NMEADTM (ASCII)
SF-3050 Sapphire SF-3040
Supported Output Rate: OFF ONCE OnChange OnTime
ONCE = output immediately once upon initiation of system
OnChange = same rate as the most frequently scheduled NAV Message
(NMEAGGA, NMEAGLL or NMEARMC)
OnTime = highest rate licensed
This output stream reports the local geodetic datum and datum offsets from a reference datum.
It is in compliance with NMEA 0183 Standards version 3.0.
Default: The NMEADTM message will be scheduled to display automatically before the
most frequent NAV msg (NMEAGGA, NMEAGLL or NMEARMC). If the frequency of any
other NAV msg is changed, the adjusted NMEADTM message will automatically display
before the most frequent one.

If the user is running an earlier version of the software (v3.0.13 and earlier), the
NMEADTM must be manually scheduled to display at the same rate as the
NMEAGGA, the NMEAGLL or the NMEARMC to meet IMO and MED certification
requirements.
The output format for this message is described in the following table.

When datum code is unknown (e.g. RTK mode), the output will be empty.
Table 143 DTM Message Output Format
Field# Field name Description
F1 Local datum code Local Datum Code
W84 = WGS84
W72 = WGS72
S85 = SGS85
P90 = PE90
999 = User defined
F2 Local datum subdivision code Local datum subdivision code (if available)
F3 Lat offset Latitude offset from reference position (in minutes)
F4 N/S Direction of latitude (N=north, S=south)
F5 Lon offset Longitude offset from reference position (in minutes)
F6 E/W Direction of longitude (E=east, W=west)
F7 Altitude offset Altitude offset from reference position (in meters)
F8 Reference datum code Reference Datum Code
W84 = WGS84
W72 = WGS72
S85 = SGS85
PE90 = P90
F9 *CRC Checksum
Output values depend on navigation mode and [DATUM] selection. Table below is a quick
reference for DTM outputs for each navigation mode and [DATUM] selection.