GPSM001
OEM GPS Receiver Module
$PXEMmaa,x1,x2,x3,x4,….,xN*hh
where
m
– command type: ‘Q’ for ‘query’, ‘S’ for ‘set’, ‘R’ for ‘response’;
aa
– proprietary command identifier (see
below);
x1…xN
– data parameters (only for
set
and
query response
commands);
hh
– command checksum
NOTE:
Each of the data parameters must be preceded with a comma, except for the
aa
command identifier, and the
checksum which is preceded with a checksum delimiter character ‘*’.
• QUERY command: to send a
query
command, no data fields are transmitted. The following format is used:
$PXEMQaa*hh
• RESPONSE command to QUERY: for a
query
command, a
response
command with all fields is transmitted. The
following format is used:
$PXEMRaa,x1,x2,x3,x4,….,xN*hh
• SET command: to send a
set
command, x1…xN must contain valid values. The following format is used:
$PXEMSaa,x1,x2,x3,x4,….,xN*hh
• RESPONSE command to SET: for a
set
command, a status
response
command is transmitted. The following format is
used:
$PXEMRaa,s*hh
where
s
is the status of the requested action: ‘A’ if the action was successful; ‘V’ otherwise.
The following proprietary NMEA command identifiers are implemented:
DI – Diagnostic Message
This command outputs a diagnostic string. It is used to report various error conditions. This is a response-only
command.
$PXEMRDI,ccccccc*hh
where ccccccc is a diagnostic string up to 50 characters
NM – Command Mask and Automatic Output Rate
This command configures the application to automatically output standard NMEA commands at a specified time
interval.
$PXEMaNM,xxxx,xx*hh
Name
Message ID
Mask
Rate
<CR><LF>
Example
$PXEMaNM
0008
01
sec
Units
Description
Proprietary NM protocol header, a-mode (S = set;
R = response)
xxxx Output command mask, hex value (see
Notes below)
xx Automatic output command rate (00 to 99)
End of message termination
Table 12 NM Data Format
Notes: xxxx is a hexadecimal value representing a 2-byte bit-mask where a specific bit sets or clears automatic output
of a particular NMEA command according to the table below. The mask is derived by combining all bits which represent
the NMEA commands which will be automatically output. For example, to automatically output GGA, GSA, ZDA, and
RMC, the bits 0, 4, 5, and 8 are set to 1 in a 2-byte mask, resulting in a hex value 0x131 (0x1+0x10+0x20+0x100). This
value is sent as an ASCII string ‘0131’ in the
xxxx
field of the NM command.
NMEA
Command
Bit#
xxxx
Field value
GGA
GLL
VTG
DS031-2 Jan ‘04
0
1
2
0001
0002
0004
Page
11
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