Simrad DAD datagram format
Simrad DAD is a proprietary datagram format created by Kongsberg Maritime to provide the ascending or descending depth rate of the trawl sensor.
Format
@IIDAD,x.x,M,y.y,M<CR><LF>
Description
1 IITalker identifier
2 DADDatagram identifier
3 x.x,MDepth (Metres)
4 y.y,MDepth changes (Metres/MinutesThe value is negative when the depth is ascending.