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13

RGPSM202

SlimGPS™ Receiver

5.3.6

RMC—Recommended Minimum Specific GNSS Data

Description: This message reports the time, date, position, course, and speed from the receiver’s navigation solution.

RMC is described in Table 14.

Name

Example

Units

Description

Message ID

$GPRMC

RMC protocol header

UTC Position

161229.487

Hh mm ss.sss

Status

A

A = data valid or V = data not valid

Latitude

3723.2475

Dd mm.mmmm

N/S Indicator

N

N = north or S = south

Longitude

12158.3416

Ddd mm.mmmm

E/W Indicator

W

E = east or W = west

Speed Over Ground

0.13

knots

Course Over Ground

309.62

degrees

True

Date

120598

Dd mm yy

Magnetic Variation

1

02.6

degrees

E/W Indicator

W

E = east or W = west

Mode Indicator

A

A = autonomous, D = differential, E = estimated,

M = manual input, S=simulator mode, N = not valid

Checksum

*10

<CR><LF>

End of message termination

Table 14. RMC Data Format

Example: The values reported in this example are interpreted as shown in Table 14:

$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598, 02.6,W,A*10

5.3.7

VTG—Course Over Ground and Ground Speed

Description: This message reports current ground course and speed data. Course is reported relative to true north only.

The VTG message is defined in Table 15.

Name

Example

Units

Description

Message ID

$GPVTG

VTG protocol header

Course

309.62

degrees

Measured heading

Reference

T

True

Course

139.6

degrees

Measured heading

Reference

M

Magnetic

1

Speed

0.13

knots

Measured horizontal speed

Units

N

Knots

Speed

0.2

km/hr

Measured horizontal speed

Units

K

Kilometer per hour

Mode Indicator

A

A = autonomous, D = differential, E = estimated,

M = manual input, S=simulator mode, N = not valid

Checksum

*6E

<CR><LF>

End of message termination

Table 15. VTG Data Format

Example: The values reported in this example are interpreted as shown in Table 15:

$GPVTG,137.7,T,139.6,M,007.4,N,013.7,K,A*47