The NMEA DBS datagram provides the current depth from the surface.The datagram is no longer recommended for use in new designs.It is frequently replaced by the NMEA DPT datagram format.
Format
$--DBS,x.x,f,y.y,M,z.z,F*hh<CR><LF>
Description
All depths are measured from below the sea surface.
1
$—: Talker identifier
2
DBS: Datagram identifier
3
x.x,f: Depth(Feet)
4
y.y,M:Depth (Metres)
5
z.z,F: Depth(Fathoms)
6
*hh: Checksum
Tip
If you need the depth below the keel, use the NMEA DBK datagram.If you need the depth below the transducer, use the NMEA DBT datagram.