GPSM001 Datasheet, PDF (10/20 Pages) rfsolutions.ltd – OEM GPS Receiver Module

OEM GPS Receiver Module
GPSM001
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 10.
Name
Example
Units
Message ID
$GPVTG
Course
309.62
degrees
Reference
T
Course
degrees
Reference
M
Speed
0.13
knots
Units
N
Speed
0.2
km/hr
Units
K
Checksum
*6E
<CR><LF>
1 _{All "course over ground" data are geodetic WGS84.}
Description
VTG protocol header
Measured heading
True
Measured heading
Magnetic ¹
Measured horizontal speed
Knots
Measured horizontal speed
Kilometer per hour
End of message termination
Table 10. VTG Data Format
Example: The values reported in this example are interpreted as shown in Table 10:
$GPVTG,309.62,T, ,M,0.13,N,0.2,K*6E
ZDA—Time & Date
Description: This message reports current time and date. The ZDA message is defined in Table 11.
Name
Message ID
Hour, Min, Sec, Sub Sec
Day
Month
Year
Local Zone Hours
Local Zone Minutes
<CR><LF>
Example
$GPZDA
114523.62
12
04
2001
10
34
Units
Description
ZDA protocol header
hhmmss.ss
day in UTC, 01 to 31
month in UTC, 01 to 12
year in UTC
local zone hours, +/- 13 hours
local zone minutes, 0 to +59
End of message termination
Table 11 ZDA Data Format
Example: The values reported in this example are interpreted as shown in Table 10:
$GPZDA,114523.62,12,04,2001,10,34*6E
NMEA SPECIFIC COMMANDS
The NMEA 0183 Standard dictates that proprietary NMEA commands have the following structure:
$Paaaxxxxxxxxxxxxx*hh
where aaa – mnemonic code, XEM in our case; xxxxxxxxx…– data; hh – command checksum
Two types of input commands are defined: query and set. Query commands request certain information from the
receiver. Set commands allow the user to configure the receiver with certain configuration parameters or force the
receiver to perform a specific action. For each type of input command, a corresponding output response command is
defined.
For a query command, the response command contains requested data. For a set command, the response command
contains the status of the action requested in the set command. Taking these aspects into account, the following is the
general structure of the specific NMEA command:
DS031-2 Jan ‘04
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