Furuno GP-90 - Manual (Page 13)

5. INITIAL SETTINGS
11
Input data sentence of NMEA 0183 Ver. 1.5/2.0
Checksum is checked if attached, and if any errors are found, the sentence becomes invalid.
Talker ID is not distinguished.
DBT: Depth below transducer
DPT: Depth
HDG: Heading, deviation and variation
HDM: Heading, magnetic
HDT: Heading, true
MTW: Water temperature
TLL: Target latitude and longitude
VBW: Dual ground/water speed
VHW: Water speed and heading.
FURUNO proprietary sentence
AGFPA: Autopilot information from FURUNO autopilot equipments.