GPRMC

GPS specific information

Platform:

OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7, SMART2

This log contains time, date, position, track made good and speed data provided by the GPS navigation receiver. RMC and RMB are the recommended minimum navigation data to be provided by a GNSS receiver.

A comparison of the position precision between this log and other selected NMEA logs can be seen in Table: Position Precision of NMEA Logs.

The GPRMC log outputs these messages without waiting for a valid almanac. Instead, it uses a UTC time, calculated with default parameters. In this case, the UTC time status (see the TIME log) is set to WARNING since it may not be one hundred percent accurate. When a valid almanac is available, the receiver uses the real parameters. Then the UTC time status is set to VALID.

If the NMEATALKER command is set to AUTO, the talker (the first 2 characters after the $ sign in the log header) is set to GP (GPS satellites only), GL (GLONASS satellites only), GA (Galileo satellites only), GQ (for QZSS satellites only), GB/BD (for BeiDou satellites only) or GN (satellites from multiple systems).

The position for the GPRMC log is reported in the user selected datum. See the DATUM command for more details.

Message ID: 225

Log Type: Synch

Recommended Input:

log gprmc ontime 1

Example 1 (GPS):

$GPRMC,203522.00,A,5109.0262308,N,11401.8407342,W,0.004,133.4,130522,0.0,E,D*2B

Example 2 (Multi-constellation):

$GNRMC,204520.00,A,5109.0262239,N,11401.8407338,W,0.004,102.3,130522,0.0,E,D*3B

See the Note in the GPGGA log that applies to all NMEA logs.

Field

Structure

Field Description

Symbol

Example

1

$GPRMC

Log header

 

$GPRMC

2

utc

UTC of position

hhmmss.ss

144326.00

3

pos status

Position status (A = data valid, V = data invalid)

A

A

4

lat

Latitude (DDmm.mm)

llll.ll

5107.0017737

5

lat dir

Latitude direction: (N = North, S = South)

a

N

6

lon

Longitude (DDDmm.mm)

yyyyy.yy

11402.3291611

7

lon dir

Longitude direction: (E = East, W = West)

a

W

8

speed Kn

Speed over ground, knots

x.x

0.080

9

track true

Track made good, degrees True

x.x

323.3

10

date

Date: dd/mm/yy

xxxxxx

210307

11

mag var

Magnetic variation, degrees

Note that this field is the actual magnetic variation and will always be positive. The direction of the magnetic variation is always positive.

x.x

0.0

12

var dir

Magnetic variation direction E/W

Easterly variation (E) subtracts from True course.
Westerly variation (W) adds to True course.

a

E

13

mode ind

Positioning system mode indicator, see Table: NMEA Positioning System Mode Indicator

a

A

14

*xx

Check sum

*hh

*20

15

[CR][LF]

Sentence terminator

 

[CR][LF]

NMEA Positioning System Mode Indicator

Mode

Indicator

A

Autonomous

D

Differential

E

Estimated (dead reckoning) mode

M

Manual input

N

Data not valid