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Heiko's GPS and electronic chart page

Some information on satellite navigation and electronics maps ...


26-Jun-2002: added link to Linux version of g7to ...
11-Jul-2001: updated G7ToWin link ...
06-Oct-2000: added note on possible DPMI/EMM386 problems with CHART286/287.EXE ...
01-May-2000: fixed CHART 1.3pre, several new (DGPS) links, ...
18-Apr-2000: new CHART 1.3pre snapshot, new GMT2CHA vector charts, ...

CHART - Electronic Chart System


CHART is a little Electronic Chart System for PCs running DOS or Win9x. It supports vector charts and bitmap charts and includes a vector chart editor. GPS data in NMEA format and in "Rockwell NavCore V" format can be received via the serial port and displayed in real time.

Vector charts created with CHART can be converted to the "track" file format used by GARMIN's PC interface software. Thus you can upload your own vector charts to a GARMIN 45 or GPS 12 (and probably most other handheld GPS navigators by GARMIN) ...

To be honest, it wasn't a bad feeling at all when I managed for the first time to see my own vector map on the GARMIN 45 display ... I switched to head-up mode and watched us sailing between the islands on that tiny display. This was something nearly as impressive as the real world outside - the Norwegian archipelago.

GMT and gmt2cha.c

GMT (Generic Mapping Tools) is a very good set of UNIX mapping programs available on the Internet. It includes a 50 MByte data base with the vectorised shoreline of the world in a resolution corresponding to an 1:250000 map. It uses WGS84 and usually has an error of only a few 100m (<500m).

GMT2CHA is a conversion tool that transforms Postscript maps generated by GMT into the vector chart format used by CHART. Thus you can make your own vector maps from the data base availabel with GMT. This is a great starting point for areas where you don't have any bitmap or vector charts available.


I really would like to thank Otto Lier for providing the greatest "programming environment" I've ever been able to work in.

Most parts of CHART were written on a Toshiba 387 notebook connected to GPS receivers like GPSPAC (Rockwell NavCore V), GARMIN 45, or GPS 12 whilst sailing in the waters of Horten and Tjøme in the Oslofjord. Thus CHART was developed, tested, and used in its natural environment.


All usual disclaimers apply! You use CHART at your own risk!

CHART may be copied according to the GNU General Public Licence.

CHART - Bug Fix & Update (01-May-2000)

  • ch000501.zip (366k) bug fix and update for ch000116.zip (requires to unpack ch000116.zip first !!!)
    now works also on PII-266 and faster (see ctbppat.zip), grmn2cha updated to support new G7To file format (see below)

NOTE (06-Oct-2000): Unfortunately, there seem to be some problems with the DPMI/EMM386 support in CHART286/287.EXE which might cause CHART and even EMM386 to crash. If you require high reliabity, use CHART86/87.EXE or run CHART286/287.EXE on a pure DOS system without EMM386. I apologise for these inconveniences and will make a fix available as soon as I manage to track down the origin of this problem.

CHART - New Snapshot (18-Apr-2000)

  • ch000116.zip (576k) CHART 1.3pre snapshot 000116
    now with DPMI support (CHART286/287.EXE) for DOS&Win (use >640k ;-), several improvements (re-align bitmap, load file with F8, dashed line on "land side" of shoreline, ...), better menu structure: see chart.hlp (ASCII text) for details!

CHART - Version CHART12X (30-Nov-1998)

CHART - Archive

G7TO Mirror (11-Jul-2001)

G7TO is free DOS program by Ron Henderson to upload and download data to Garmin GPS receivers using their GRMN/GRMN protocol. When running Windows, the G7TOW or G7TOWIN versions usually work better, but might need 401comupd.exe to update COMCTL32.DLL (see G7ToWin web page for details). For newer versions, check the original G7ToWin web page http://members.home.net/crh24/gps/g7towin/g7towin.htm (new URL since 2001).

G7TO for Linux (April 2002)

In April 2002, David Gesswein ported G7TO to Linux and made this version available at ftp://ftp.pdp8.net/g7to/ (local mirror as of 2002-04-16: README.TXT, g7to.tgz, g7todoc.tgz). To convert the output of this Linux-G7TO into an older DOS-G7TO format understood by my GRMN2CHA converter, I've hacked a tiny script g7to-way2dos.

CHART 1.3x screenshot (01-May-2000)

[CHART 1.3x screenshot]

Overview of charts in GMT2CHA version 4 (18-Apr-2000)

Norway/Sweden:   nose4*.zip     [full size GIF] [PDF]


Germany/Denmark:   dedk4*.zip     [full size GIF] [PDF]


Links (01-May-2000)


Heiko Purnhagen <purnhage@tnt.uni-hannover.de> 2004-12-18