Garmin eTrex GPS Receiver User Manual


 
46
Appendices
Appendix E
Wiring Diagram
Interface formats are selected from the SETUP Page.
The input/output lines on your eTrex are RS-232 compat-
ible, allowing easy interface to a wide range of external
devices, including PC’s, differential beacon receivers,
marine autopilots and/or a second GPS receiver.
The NMEA 0183 version 2.3 interface format is
supported by the eTrex and enables the unit to drive up
to three NMEA devices.
NMEA 0183 Version 3.0 Approved Sentences:
GPGGA, GPGLL, GPGSA, GPGSV, GPRMB, GPRMC,
GPRTE, GPVTG, GPWPL, GPBOD
Garmin Proprietary Sentences:
PGRME (estimated error), PGRMM (datum string),
PGRMZ (altitude), PSLIB (beacon receiver control)
DGPS (Differential GPS) corrections are accepted in
RTCM SC-104 version 3.0 format through the ‘Data In’
line. The Garmin GBR 21 and GBR 23 are the recom-
mended beacon receivers for use with the eTrex. Other
beacon receivers with the correct RTCM format may be
used, but may not correctly display status or allow tuning
control from the GPS unit.
The eTrex may be hard-wired to a serial connec-
tor using the Data Cable (see the Garmin web site,
www.garmin.com for ordering information). Refer to
the wiring diagram and the eTrex unit data connection
illustrated below.
The optional PC Interface Cable allows you to connect
your eTrex to a PC-compatible computer’s serial port.
Power (+)
Data Out
Data In
Ground (-)
Ground (-)
Data Out
Data In
Green
White
Black
Data Cable
eTrex
Connector
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