SXBlue II GPS Series Technical Reference Manual
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4. Complete NMEA Interface
The SXBlue II GPS supports a selection of NMEA 0183 and proprietary binary
messages. The following chapter describes the NMEA interface in detail and chapter 5
defines the Binary messages. It’s your choice as a systems designer to choose whether
or not to support a NMEA-only software interface or a selection of both NMEA and
binary messages. The SXBlue II GPS is configured using only NMEA commands.
4.1 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:
$XXYYY,zzz,zzz,zzz…*xx<CR><LF>
The components of this generic NMEA message example are displayed in Table 4-1.
Table 4-1 NMEA Message Elements
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
Null, or empty fields occur when no information is available for that field.
Factory default settings are shown with an “
*
” next to the values.
4.2 General Commands
This section presents various commands relating to the general operation and
configuration of the SXBlue II GPS. The following table provides a brief description of the
general commands supported by the SXBlue II GPS receiver.
