The Garmin Home Page has software upgrades for some Garmin receivers (be SURE you get the right one for your receiver!!), as well as a FAQ, manuals for many products, and other information.
Purple Computing (Larry Berg) has power and data connectors for Garmin 45 and similar receivers (38,40, II, 12xl...). He also shows a cable wiring diagram.
Ready made cables using Larry's connectors are available from Dave Sorenson
The Official Garmin Protocol Specification is available from http://www.garmin.com/support/protocol.html (currently Rev. 3, Dec. 1999)
Garmin Protocol Description by John Waers (html format, 11388 bytes)
Mats Rosengren has provided yet another Garmin protocol description.
Garmin.txt (27268 bytes) is another description of the Garmin protocol, by William Soley, Eric Werme, Anton Helm and Daniel Zuppinger. (last update March 6, 1998)
Tom Born's Garmin GPS PagesFlyingD's GPS FLIGHT TRACK ANALYZER is a Freeware DOS program (small, very fast and works on anything) that will analyze GarminŽ GPS-90 track files and will profile your flight returning the following data and more: take-off time, landing time, total time, total flight time, total distance, flight distance, average groundtrack, direct route distance, efficiency of the flown route, average groundspeed, taxi & take-off run at departure, landing run and taxi at arrival.
Gardown11 (57,568 bytes, rev. Sept./97) transfers waypoint, route, and track data between a Garmin GPS to a PC, and can log NMEA-0183 data. (MS-DOS) The latest version is available from the GarDown home page By Mike Montgomery (mike@anali.demon.co.uk) Older versions are also available: gardown8.zip, gardown9.zip
GarTrack is a Windows95 program for performance analysis for regatta sailors using data from a Garmin GPS. GarTrack uses the data stored in the GPS tracklog-file during the race. Diagrams and tables provide insight in the relations between boat speed, wind speed and direction. For further information, see http://www.otw81.brijn.nu
GPSdb is a waypoint database program for use with Garmin receivers. It requires Win95 or WinNT. The program will upload and download waypoints, tracks, and routes. It will import from GarDown files. Waypoints can be created in this program and uploaded to the GPS. Routes can be created by "drag and drop". It also exports waypoints and tracks in Street Atlas format. Includes various map datums. More info and downloads at http://blkbox.com/~hub/gpsdb. From Tim Hubbard (hub@blkbox.com)
GARNIX is an MS-DOS program to up/download waypoints, routes, etc. from a Garmin GPS . The package includes a program to convert between Lat/Long, UTM and other grids, and to convert datums.
GPS Utility is a freeware/shareware program for users of Garmin or Magellan GPS receivers. As well as upload/download, it provides facilities for mapping, sorting waypoints, filtering and selecting GPS data, digitising from scanned maps, track analysis and other advanced tools (for example, generating waypoints/routes from tracks). A variety of grids and coordinate formats are supported together with the import/export of many different file types. The program exists in both 16-bit and 32-bit versions and includes an extensive help system. For more information see http://www.gpsu.co.uk/
Thomas Ott Thomas Ott has a program called GPS2PILOT2PC . This program allows the USR/3Com PalmPilot to track transfer data to/from a Garmin GPS. The program can also make the Pilot look like a Garmin GPS to a PC, so the usual Garmin protocol programs can be used to transfer the track data between the Pilot and a PC (or Mac, I suppose...)
GARtrip is a Win3.1/Win95 shareware program for users of a Garmin GPS receiver by Heinrich Pfeifer.
Main Features:
Garmin_GPS_xla_01c.zip (15,492 bytes) contains the source code for an Excell Add-in (VB for Apps) which converts GarDown7 track data to a *.dbf file, and converts the Lat/Long to the Swedish National grid.
Garmin32.zip (for Win95, 211K, July 28/97) is another program to up/download waypoints, tracks, etc. between a Garmin GPS and a PC. By Klaus Voigt (kpv@pcpostal.com)
Waypoint+ is a Windows95 program to transfer waypoints, routes and tracks between Garmin receivers and a PC. It will write the data as a text file, or in formats compatible with DeLorme Street Atlas 3.0 or 4.0, or Map Expert 2.0. By B. Hildebrand (bhildebrand@worldnet.att.net) See the Waypoint+ home page for further information and to download the program
MacGPS45.zip (59797 bytes) contains the source code and design notes (including a description of the Garmin protocol) for John Waers' (jfwaers@csn.net) MacGPS-45 Macintosh program, which transfers waypoints, routes, etc. between a Garmin GPS and a Mac. This file has been converted to a DOS archive (and a MacWrite document converted to WordPerfect), but the program has not been ported to DOS. The original Mac format source archive and program are available from ftp.csn.net/Unimac. Please note that both these files contain the source for an early, somewhat buggy version of MacGPS. The commercial version of this program is available from http://www.macgpspro.com/GPSPRO.html
GPS Manager (GPSMan) is a graphical manager of Garmin GPS data and lets you prepare, inspect and change GPS data on a friendly environment. Note that GPSMan was thought of for use at home and not for real-time use. GPSMan is a stand-alone Tcl/Tk program that implements part of the Garmin GPS Interface Specification. This program was apparently developed under Linux. The author's site gives a source for a Windows version of Tcl/TK which will allow it to be used under Windows.
GPSTrans is a Linux program based on MacGPS. It will upload/download waypoints, tracks, routes, and almanac from a Garmin GPS. Written by Carsten Tschach (tschach@zedat.fu-berlin.de). This file contains "tarred and zipped" C source. Another version, with some additions or corrections is gpstrans-0.31b-js1.tar.gz (84,415 bytes), by Janne Sinkkonen (janne@avocado.pc.helsinki.fi) (I'm told the -js1 version is for Linux, the other is for Sun/HP)
gd2: This C language program (inspired by GarDown) is designed to download tracks, routes, waypoints, position, clock, and almanac and to upload routes and waypoints from/to Garmin 12xl, Garmin 38 and Garmin 45. The package includes man page, makefile, and notes. It works well on Linux and FreeBSD, and needs help for SunOS. Available as a .shar file: gd2.shar (70662 bytes) or gzipped tar: gd2.tgz (18415 bytes) Oct. 21, 1997. By Randolph Bentson (bentson@greig.seaslug.org)
gsa14.zip (53,423 bytes, Jan 22/97) contains some programs by Lance Rose (lancer@netrix.net) to exchange waypoint data between a Garmin 45 (and probably most other models) and a DeLorme Street Atlas 3.0 map file (.SA3) using the Garmin protocol. They let you create waypoints with the map program and upload them to the GPS, or download the waypoint database from the GPS to a specified map file for later manipulation.
G7To and G7ToWin convert GarDown7 download files to Street Atlas 3 format, or vice versa, and converts either format to formats compatible with PROJ.EXE, NAD2NAD.EXE, or UTMS.EXE. This version can also communicate directly with a Garmin or Lowrance receiver.
capg7100.zip (31045 bytes) includes a program to capture NMEA-0183 data at user-defined intervals, and some batch files that semi-automate the conversion between the files captured with this program and SA3 files. Can be used in conjunction with g7to and gardown7. (by Richard Hess rlh@interramp.com)
gmn_dxf2.zip (46093 bytes) converts the data downloaded by gardown into a .dxf file for import into AutoCad or other drawing programs that read this format. (from DNelson@lanl.gov)
psigar20.zip (25925 bytes) is a shareware program to transfer waypoints, routes, track logs, etc. between a Garmin 45 (not tested with other models) and a Psion series 3A
GarMap.zip (10878 bytes) provides an interface between Mapinfo Desktop Mapping Software and a Garmin GPS receiver, using the proprietary Garmin/Garmin protocol. (from mholdern@sctyhq1.telecom.com.au)
Garmin Data Monitor (229905 bytes) uses the Garmin protocol to display information not available via NMEA-0183, such as satellite status, more precise position to display SA "wandering", etc.
wayuk11.zip HPx00LX palmtop databases of waypoints and segmented road track logs fo rthe UK. The databases have been set up to allow their partial upload to a Garmin GPS45 with the G7TO203 program so you can get a relatively detailed moving map display on your GPS without exceeding its memory capacity. By John Seymour (john@blackbirds.demon.co.uk)