Garmin 126 to Laptop

Biggles · 15 March 2005, 19:49

I am trying to connect my Garmin 126 to a laptop.

I am doing this via the USB port. Although the official Garmin cable has a DB9 serial port I have a USB adaptor that mimics a COM port.

When I go to Find Device the computer looks for the GPS for a few seconds then tells me I have an errror. The fact that it takes a few seconds to look for it indicates that the laptop has detected something.

What isn't clear from Garmin is what protocol the GPS should be set to to send and recieve Data. Although it says NMEA in the manual and web site their appear to be several flavours of NMEA. I've tried them all, I think, but am still having no luck.

Has anybody got this type of setup to work ?

I have also tried Easy GPS but this doesn't work either.

I built the cable myself following Garmins on site instructions and am pretty sure I have connected it correcly. However if somebody says it should be working then I will go back and check my soldering etc.

Regards Nick R.

roohairy · 16 March 2005, 07:29

I connect GPS's like this and have had two problems.

The com port can change depending on which USB port I plug it into. I always plug it into the same one now and that's solved one problem.

Another problem is that if you boot up a PC with the GPS attached it sometimes detects it as a serial mouse, if your cursor jumps all over the place this is what's happening. I've cured this by booting up, then plug in USB serial port, once that's been detected plug in GPS and all will be fine (for me at least!)

Garmin wiring has 4 wires, red (+) black (-) and 2 data colours which I can't remember. Black is also signal ground, connect to pin 5. Data in is pin 2, Data out pin 3.

Use Hyperterminal to check your connections, any NMEA standard will do for this only becomes relevant when you connect to other equipment. I think (?) on the 126 you can change the baud rate between 4800 and 9600 and possibly others, it will probably be set to 4800 so try that first.

Good luck, and if this is not enough detail get back to me! Email me if you want as I don't get on here very often now.

Biggles · 23 March 2005, 16:52

Hi Roohairy,

Thanks for the info.

I've given it another try and things haven't got any better. I checked the wiring and thats all correct, including inside the GPS itself all the way to the circuit board. I have also tried a PC with a DB9 connector and this makes no difference.

Mapsource does spend some time looking for a GPS (approx 10 secs) But can't find anything.

I've scoured the Garmin web site and can't find any more info.

I'm going to give it a break now for a few days but if you can think of anything drop me a line.

Jeff · 23 March 2005, 19:53

[QUOTE=Biggles] Hi Roohairy,

Thanks for the info.

I've given it another try and things haven't got any better. I checked the wiring and thats all correct, including inside the GPS itself all the way to the circuit board. I have also tried a PC with a DB9 connector and this makes no difference.

Mapsource does spend some time looking for a GPS (approx 10 secs) But can't find anything.

Hi,
Are you just trying to download waypoints and routes to your laptop using a proprietary piece of software ? If so have you tried setting the GPS to : Garmin: Garmin - which I think is correct for data transfer . It certainly works using Gartrip and did do with some old DOS software that MArine Electronics used to ship free with GPS. Don't forget to change settings back afterwards !

Hope this works/helps
Jeff

If I am barking up the wrong tree ( as often) - apologies

Biggles · 23 March 2005, 20:32

Jeff

Its just to save and download waypoints and routes.

I'm sure I've tried setting the interface to Garmin. It may be Mapsource that is my problem. I have version 6.5 but only version 4 of the Bluechart Data.

I'm going to give it a go with Easy GPS tomorrow.

Cheers Nick R.

jwalker · 23 March 2005, 23:30

I came across this FAQ link on Garmin's site. It may be of help.

http://www.garmin.com/support/faqs/faq.jsp?faq=415

Biggles · 24 March 2005, 00:18

JW

I've seen and read that. My USB to DB9 cable seems to be working ok with the drivers etc.

Are you sure the GPS settings are Garmin/GARMIN. If so that would be a bit of a start and something I could forget about changing from NMEA/None/Garmin/NMEA/ etc.

Then I can concentrate on the software side.

Regards Nick R.

roohairy · 25 March 2005, 00:26

Biggles,

Have you tried to see data with hyperterminal?

Set GPS I/O to none/NMEA or NMEA/NMEA and make a note of the baud rate, probably 4800 but may be different.

On your PC, Start/Programs/Accessories/Communications/Hyperterminal.exe

Name your connection, select the appropriate com port to connect with instead of your modem if it's defaulted to that, Set your baud rate in bits per second, data bits should be 8, parity none, and it should work with 1 stop bit and hardware flow control just fine.

You should now see the NMEA sentences being displayed on the screen, if not I can't think of anything else at the moment! If you've already done all this I apologize, just saying what I'd do next.

You could also try swapping the data in data out wires incase they're the wrong way round, won't do any harm. Black should be pin 5, brown (from memory) is data out and should be pin 1

Good luck....

roohairy · 25 March 2005, 00:28

Yes, deliberate mistake, pic's from a different GPS.
Sorry!

Biggles · 25 March 2005, 18:19

Roohairy,

Thanks for the info. I am working all the bank holiday weekend but will give that a try next week.

I will keep you posted.

regards Nick R