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HOW TO – Garmin eTrex data cable

HOW TO – Garmin eTrex data cable

Datacable Connection
Jens writes – “I have read your blog entries for GPS data loggers. Instead of getting one of those stand-alone data loggers, I would suggest to get a Garmin e-Trex. This is a standard GPS handheld receiver for outdoor use. They sell for about 100$, collect 10000 data points and run 22 hours on AA cells. And because these have a display and more functions they can also be used for outdoor activities. I wouldn’t save those 5$ and get only a data logger with much less functionality. And even better, you can MAKE the data cable yourself. I made one and it is very easy.”Link.


  • A cheap GPS loggers… Link.
  • Where conference – Link.

20 thoughts on “HOW TO – Garmin eTrex data cable

  1. monopole says: provides open source cables for the garmin. the Garmin Gecko 201 is yet smaller and cheaper than the eTrex.

  2. Oracle1729 says:

    From the article you linked to, it looks like they cable you build is only useful to load routes and data into the GPS, not use the GPS as a datalogger.

    It’s a useful project, and a great alternative to wasting $50 on the cable if you have the GPS, but it doesn’t do the same job.

    Having a lot more functionality then “only a data logger” doesn’t do much good when it can’t function as a datalogger and a datalogger is what you need.

  3. jswilson64 says:

    Garmin GPS receivers with PC cable ports are able to do 2-way communications with PC. My eTrex Legend can upload and download info. I use it on my bike to compare my route to the available maps of the trails I ride.

    Using the eTrex as a data logger would simply require turning track-logging “on” and setting the interval so that it doesn’t fill the memory too quickly.

  4. note23 says:


  5. Mugros says:

    1. I am the one who submitted the website. But i am not Jens. Sorry, if this wasn’t clear.

    2. Oracle1729: As you can see in the picture there is one cable for transmit and one for receive.

    You can use the device as a stand-alone datalogger without the cable just like the Wintec device that was submitted before. The only drawback is the slightly lesser capacity and no wireless BT connection. But the 10 h battery life just isn’t enough for a whole day of data logging. The etrex can even be powered externaly, but the battery life is already great. And the other features are almost the same. You can also change the logging interval and is has circular recording. The etrex ist also IPX7 certified, so it is pretty waterproof.

    With the cable you can use the etrex as a GPS receiver for every common map/routing program, so you can see your position in the program on a map and you would have almost unlimited capacity. Of course, it supports the NMEA standard, as well as a couple of other protocols. AFAICS all programs use the COM serial port for communicating. So with the Wintec you would have to emulate a serial port via BT or USB.

  6. Oracle1729 says:

    Mugros, you seem to not understand what transmit and recieve lines mean in a serial cable.

    It has nothing to do with what the software in the GPS can do.

  7. bmsinc says:

    I did this over the weekend and it works fine. I added instructions of my own on my blog at

    I tried this gps device with the cable using Microsoft Steets and Trips 2007 and had no problem at all. It was accurate and showed me my position on the map!

    This was a great alternative to buying a usb gps device that needs to be externally powered with no screen display. I got my eTrex for $40 and the serial cable for $10 – cant beat that for GPS!

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