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Silva Atlas GPS pinouts

The Silva Atlas GPS is actually just the same device as the Lowrance iFinder and the Brunton Atlas.

It took me quite a while to figure this out. Swedish Silva(TM) did not want to give me the pinouts for the unit, but it seems Lowrance has got another policy
Fantastic.
Lowrance iFinderBrunton AtlasSilva Atlas

Pin outs for Silva Atlas/Lowrance iFinder/Brunton Atlas

Oh, and the 9-pin RS-232 cable pinouts:

Pin Function Connect to
Pin 2 NMEA "A" (Receive data) GPS Data out (+)
Pin 5 NMEA "B" (Signal ground) GPS Signal ground (-)
Pin 3 Transmit data GPS Data in (+)

Lucky me, I’ve got a “Cig Plug Power Adapter (Art.no.22608)” that I have modified according to the pinouts above, and
IT WORKS

So, grab your old mouse, cut off the COM plug and connect it according to this (at your own risk, of course…):
Pin outs for Silva Atlas Brunton Atlas Lowrance iFinder GPS

It works just fine with a USB to RS-232 (COM) adapter and the GNU/Linux application gpsdrive:

  1. Connect the GPS to your computer/laptop through the USB-COM converter/adapter
  2. Turn the GPS on, activate NMEA serial output
  3. If necessary, change the permissions on /dev/ttyUSB0 (or whatever your tty is) as root type ‘chmod a+rw /dev/ttyUSB0‘ (better suggestions appreciated, i.e. by using udev or something…)
  4. Start gpsd: 
    $ /usr/sbin/gpsd -N -n -D 2 /dev/ttyUSB0
  5. Start gpsdrive

Update: Because my cable is not “handshake” connected (i.e. connect pin 1-4-6, see this link), I’ve made the following script (to be run as root):

#!/bin/sh
killall gpsd
mknod /dev/ttyUSB0 c 188 0
/usr/sbin/gpsd -N -n -D 2 /dev/ttyUSB0

It works fine when I first connect everything, then turn on the GPS (with NMEA output activated), run the script above, at finally start gpsdrive as normal user.

(The full path to the gpsd daemon is important – for some reason, I’ve got two versions installed on my system, I don’t know how to get rid of the one that shipped with Fedora Core 4, but I installed the newest one by ‘rpm -Uvh gpsd-2.28-1.i386.rpm gpsd-devel-2.28-1.i386.rpm gpsd-clients-2.28-1.i386.rpm‘, after downloading them from here, and gpsd ended up in /usr/sbin/.)

More info about the Lowrance iFinder here (and here), the Brunton Atlas here and the Silva Atlas here (products->Atlas)

Also, check out Pocket GPS World, and their forums

This blog entry is listed at repair4gps.org‘s GPS disassembly page. Also, check out tuxmobil.org‘s GPS page.

This entry was posted on Monday, July 11th, 2005 at 22:46:44 and is filed under Generell, GNU/Linux [in English]. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

22 Responses to “Silva Atlas GPS pinouts”

  1. Ken Says:
    August 24th, 2005 at 08:07:09

    One question? Can the full 12 volts from the cig lighter be used or is stepping down the voltage necessary?

  2. Oscar Says:
    September 10th, 2005 at 10:57:03

    Can the Silva Atlas Pro use the maps and all software from iFinder?

  3. Martin Says:
    September 10th, 2005 at 13:23:27

    I don’t know, but I would guess so. My Silva Atlas uses maps of the proprietary format “.lcm” which I believe stands for “Lowrance Compiled Map”. For example, the maps for Norway, Sweden, Finland and Denmark is called “000-0108-031_F19 Swe_Den_Nor_Fin.lcm”. Unfortunately there is no way to convert to/from this format (I think).

    If you know any good free software (preferably for GNU/Linux) please let me know :)

  4. CBR Says:
    October 12th, 2005 at 18:04:40

    Is it possible to download the maps for Silva Atlas load them to a SD card?

  5. Martin Says:
    October 13th, 2005 at 14:02:26

    You mean – if I could place my .lcm file out on the web for everyone to enjoy? Would love to, but that would make me a pirate… Sorry.

  6. CBR Says:
    October 13th, 2005 at 15:41:40

    Yeahr I understand you – If i happend to find a trial or somthing – I can just load it on the SD card?

  7. Martin Says:
    October 14th, 2005 at 12:07:11

    Yes you can just put the .lcm file on the SD card :)

  8. Ronnie Says:
    October 19th, 2005 at 20:11:45

    Where can i buy this: 000-0108-031_F19 Swe_Den_Nor_Fin.lcm

  9. Martin Says:
    October 20th, 2005 at 08:07:15

    Sorry, but I don’t know. I got mine from a friend who ordered it from Sweden through his company. I guess you can search for ‘maps OR map Silva OR Lowrance OR Brunton gps norway sweden’ in Google’s Froogle (http://froogle.google.com)

    Hey, I found this:
    Lowrance FreedomMaps F19 Sweden, Denmark, Norway and Finland

  10. Tero Karvinen Says:
    December 17th, 2005 at 08:15:41

    Your mknod script above made my Haicom HI-204E USB work. Before the script, it did nothing, because there was no device to connect to. Tested it with Ubuntu 5.10 Breezy Badger, gpsd 2.28.

  11. Tero Karvinen Says:
    December 17th, 2005 at 08:36:09

    This is how to use mknod to make HI-204E USB work:
    http://www.iki.fi/karvinen/haicom_hi-204e_usb_gps_on_linux.html

  12. Martin Says:
    December 17th, 2005 at 10:15:33

    Great :)

  13. Martin Says:
    January 26th, 2006 at 18:47:56

    For my own reference, these are the Lowrance FreedomMaps:
    F16 Deutschland
    F17 France, Monaco
    F18 Great Britain, Ireland (limited detail for Ireland and N. Ireland)
    F19 Sweden, Denmark, Norway, Finland
    F20 Italy, Switzerland, San Marino, Liechtenstein
    F21 Netherlands, Belgium, Luxembourg
    F22 Spain, Andorra, Portugal
    F23 Austria, Czechoslovakia (Chech republic), Poland

  14. Ellen Says:
    April 3rd, 2006 at 15:30:28

    Do you know some details of the *.lcm format? Silva don’t tell me something about that.

  15. Martin Says:
    April 3rd, 2006 at 17:23:08

    Ellen: Sorry, don’t know much other that it is for sure not an open format.

  16. Kirbert Says:
    January 23rd, 2007 at 17:51:14

    Thanks so much! I had a Garmin eTrex and was using a homemade data cable with it, but I gave it away to a relative. I have the Lowrance iFinder GO on order, was looking for how to connect it up without paying $30 for a piece of wire.

    BTW, my EasyGPS software lists the iFinder GO. I think that means we can all forget about trying to figure out what format to use: just use EasyGPS to load data into your Lowrance or Silva Atlas or Brunton or whatever.

  17. Kirbert Says:
    January 28th, 2007 at 09:46:41

    OK, I have the iFinder GO in hand, and the EasyGPS software doesn’t work. A freeware package called GPS Utility, from

    http://www.gpsu.co.uk

    does work, though. The freeware version is limited to 100 waypoints at a time, but that’s not a problem.

    BTW, you have to go to “System Setup” on the iFinder GO, then to “Com Port”, and check the boxes for “NMEA Input” and “NMEA Output” before transfers to/from the iFinder will work. I just left the baud rate at the default 4800, but it wouldn’t surprise me if you can speed it up and it’ll just work faster.

  18. Hollito Says:
    February 6th, 2007 at 14:17:07

    Thanks for the information! I’m thinking about buying an IFinder Go2 and was searching just for this, because 30 Euros for the data cable is a little bit overpriced in my opinion.

  19. Chuck G Says:
    March 5th, 2007 at 23:47:09

    I see the drawing on the ifinder port and understand making a serial connection – but what’s the part about a cig lighter adapter – you didn’t hook this up to your cig lighter did you?
    If I want to just use the Ifinf=der go as a GPS for say MS Streets and Trips – do I just make this cable, get a Male serial end and a USB connection adapter and hook it to the USB port and windows and MS Streets and Tril will find it without doing any hand shaking, or what? thanks

  20. Hollito Says:
    March 6th, 2007 at 15:25:17

    @Chuck
    I am not shure about what Martin wrote about this cig lighter, as he did not mention it again. But I think you could build a “2 in 1″ serial/power cable and just use the “+” and “-” contact on the Ifinder to supply it with a *stabilized* 3V power from the cig lighter socket in your car.

    What you say about the data cable and using a navigation/routing software is generally right, but nobody will guarantee you that the serial->USB adaptor will work properly. From what I have learnt in the GPS boards, some people where successful with a cheap 5 Euro adaptor, while other bought one for 25 Euros and had a lot of trouble with it… I have no experience with this, as both my notebooks have serial ports I can use… :-)

    Regards from grey and rainy Germany, Hollito

  21. Hollito Says:
    March 6th, 2007 at 15:42:38

    I forgot to mention this link, it shows how to make a simple “plug” for the GPS unit from a piece of plastic, like an old CC or so:

    http://www.jens-seiler.de/etrex/datacable.html
    http://www.jens-seiler.de/etrex/andere_stecker.html

    Regards, Holger

  22. Martin Says:
    March 6th, 2007 at 17:42:09

    Chuck G: Hollito is right – I used my cig lighter plug to make a two-in-one plug, so that I didn’t have to build the plug that goes into the GPS unit. This way, I can connect it to my laptop in a car and at the same time give the unit power from the cig outlet.

    After I wrote this post, the open source project gpsbabel finally supports the lcm-format :) Haven’t tried it too much, but this is some of my old ramblings (probably outdated):

    $ tar xzf gpsbabel-1.2.8-beta20060219.tar.gz
    $ cd gpsbabel-1.2.8-beta20060219/
    $ make
    $ su -
    # make install
    $ gpsbabel -t -r -w -i lowranceusr silva-atlas-lowrance-track-format.usr

    Have fun :)

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