Garmin GPS 18 USB Deluxe Portable Navigator 010-00321-00 User Manual

GPS 18 Technical Specifications (190-00307-00)

Rev. D

Page 7

•  GPS 18 USB:

USB 2.0 full-speed protocol compatible, as well as USB 1.1 full-speed protocol.

•  GPS 18 PC and LVC: TIA-232-F (RS-232) compatible asynchronous receiver. Default setting is 4800

baud. 

•  GPS 18-5Hz:

TIA-232-F (RS-232) compatible asynchronous receiver. Default setting is 19200
baud. 

Refer to the Garmin Device Interface Specification for information about the Garmin USB Protocol. The
document is located on the Garmin Web site at: 

 See

also 

for additional information concerning access to raw pseudo-

range and carrier phase data from the GPS 18 USB.

Refer to the Garmin Device Interface Specification for details on the Garmin interface. At the time of this
printing, these specs are available from the technical suppport section of our Web site:

•  NMEA 0183 Version 2.0 or NMEA 0183 Version 2.30 (Version 2.0 is factory default, programmable

by data field 7 of the PGRMC1 sentence described in Section 

•  Available NMEA 0183 output sentences include GPALM, GPGGA, GPGSA, GPGSV, GPRMC,

GPVTG, GPGLL, PGRME, PGRMF, PGRMT, PGRMV, and PGRMB (Garmin proprietary
sentences). See Section 

 for format descriptions.

•  Configuration and initialization is accomplished with NMEA 0183 input sentences. Allows

initialization of information such as expected position, date, time, earth datum, and differential mode.
See Section 

 for format descriptions.

•  Configurable for binary data output including GPS carrier phase data.

•  GPS 18 LVC: 1 Hz pulse with programmable width, configurable in 20 ms increments form 20 ms to

980 ms. See Section 

 for details about configuring

the Measurement Pulse Output (or PPS) feature.

•  GPS 18-5Hz: 5 Hz pulse synchronized with the time of fix. One of the five pulses will align with the

UTC second boundary. The pulse width is programmable from 20 ms to 180 ms. The PGRMC
sentence will indicate which pulse is at the top-of-the-second. See Section 

 for details about configuring the Measurement Pulse Output (or PPS) feature.

•  1 µs accuracy for all conditions in which the GPS 18 LVC or GPS 18-5Hz has reported a valid and

accurate position fix for at least the previous 4 seconds.