Nmea 0183 Messages; Nmea Message Elements; Pocketmax; Table6-1 Nmea Message Elements - CSI Wireless Vector Sensor Reference Manual

6. NMEA 0183 Messages

This chapter identifies the selection of standard and proprietary NMEA 0183 messages for the
Vector Sensor receiver.

6.1 NMEA Message Elements

NMEA 0183 messages have a common structure, consisting of a message header, data fields,
checksum, and carriage return/line feed message terminator. An example NMEA sentence follows.
The components of this generic NMEA message example are displayed in the following table.

Table6-1 NMEA Message Elements

Null, or empty fields occur when no information is available for that field.

6.2 PocketMAX

CSI Wireless offers a configuration program designed for Windows PocketPC software that runs
on PocketPC 2000, 2002 and 2003 platforms. It can be used to configure and monitor your
differential source, GPS messages and it also records various types of data. It is available for
download from CSI's website. This utility is discussed in the PocketMAX Manual and a screen-shot
is shown in the following figure.
Caution – It is important to note that when you are using PocketMAX, the program is
doing many operations behind the scenes. This includes modifying the data output
from the serial port as the program require, which is screen dependant. When you
close PocketMAX, it will give you a message confirming the current settings. It will
then ask you if you want to proceed and save these settings or go back and change
them. Once you have the settings configured properly for you, it is imperative to let
the program close completely on its own before you disconnect or power down the
receiver. This may take up to 10 seconds. If this is not performed, the receiver will
not be configured as you feel it should, and can output a mixture of binary and NMEA
data.
Vector Sensor Reference Manual
$XXYYY,zzz,zzz,zzz...*xx<CR><LF>
Element Description
$ Message header character
XX NMEA Talker field. GP indicates a GPS talker
YYY Type of GPS NMEA Message
zzz Variable Length Message Fields
*xx Checksum
<CR> Carriage Return
<LF> Line Feed
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