Garmin Apollo CNX80 Installation Manual - page 143
Appendix B - Serial Interface Specifications
GNS 480 (CNX80) Installation Manual 560-0982-01 Rev A
B-15
B.2.1.4.6 Distance/Speed/Time
Message
If an SL30 is connected to the GNS 480, the GNS 480 will send the following message to the SL30.
$PMRRV41rrrrssshmm
rrrr is the distance to the station in 0.1nm units
sss is the ground speed in knots
hmm is the time to the station in hours and minutes
This message is used to output the range, ground speed, and ETA decoded from an external RNAV
sensor (DME or GPS).
Message format:
“V” ............Message class. This is a VHF NAV message.
“41” ...........Message identifier.
rrrr .............Range from DME station in 1/10
th
of a nautical mile units. The first two digits are the
10s and 1s place of the range, and the last digit is the 1/10
th
s place. This field may range
in value from 0.0 NM (“0000”) to 999.9 NM (“9999”). If the distance from the DME
station is greater than 999.9NM, the value should be encoded as “----”.
sss ..............Ground speed with respect to DME station in knots. This field may range in value from 0
knots (“000”) to 999 knots (“999”). If the ground speed with respect to the DME station
is greater than 999 knots, the value should be encoded as “---”.
hmm...........Time to station in hours and minutes. This field may range in value from 0 hours and 0
minutes (“000”) to 9 hours and 59 minutes (“959”). If the time to the station is greater
than 9 hours and 59 minutes, the value should be encoded as “---”.
Example message:
$PMRRV410983055147
Range from DME station is 98.3 NM, ground speed with respect to station is 55 knots, and the
estimated time to the station is 1 hour and 47 minutes.