Replies to This Discussion

Permalink Reply by Bot Thoughts on May 8, 2012 at 8:20am

I thought the DIYdrones version transmitted a binary protocol unique to DIYdrones? If so, I don't see how MiniGPS could work; it was designed to support the standard protocols found on every other MTK3229.  I don't know if it's possible to tell the GPS to send NMEA output but if so you could try that.

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Permalink Reply by Rick Eis on May 8, 2012 at 8:46am

Hi Bot Thoughts,

Well, that is a good question for the experts :)  Which I certainly am not, I'm just learning and having fun :)  !!!!!

Is there an expert out there that has the answer or that can confirm what Bot Thought is thinking ?  :)

Does this particular MTK3229 transmit a binary protocol unique to DIYdrones?

Thank you in advance for your answer. :)

Rick

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Permalink Reply by Bot Thoughts on May 8, 2012 at 8:57am

If you look at the product page you will have your answer:

"Note that the new MediaTek has custom and exclusive "DIYDrones" firmware that allows the unit to output an efficient and very compressed binary protocol (This firmware will only work with our modules!). You can still change between NMEA and Binary protocol with standard MTK messages"

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Permalink Reply by John Bond on May 8, 2012 at 1:04pm

The GPS defaults to NMEA mode at 38400 baud when powered up.  It has to be commanded to go into DIYD binary mode which the DIYD autopilot software does.

It's simple to talk to the GPS with MiniGPS.  You just need the correct connections.  Assuming you have a Windows PC with a USB port just get a FTDI cable like:

http://www.sparkfun.com/products/9718

connect that from your PC to another little adapter cable:

https://store.diydrones.com/FTDI_GPS_Adapter_cable_15_cm_p/ca-0001-...

which connects to the GPS.  No soldering or cutting wires required.  The USB port powers the GPS.

Start up MinIGPS and connect to the serial port number the FTDI cable created @ 38400 baud and you are in business.

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Permalink Reply by Rick Eis on May 8, 2012 at 8:47pm

Thanks John,

I kind of figured and/or was hoping it was this simple. :)   Thank you for your detailed answer !!

It appears by this and some of your other posts that you know quite a bit about these little GPS units.  Do you have a programming background or is this just a hobby ?

Have you ever connected one of these up to an arduino board?

Thanks again for your thorough answer !!  

Rick

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Permalink Reply by Ken on May 11, 2012 at 4:25pm

Yes, they connect fine to an Arduino. I've used them with Diecimila, Uno, BareBones, and SparkFun 3.3v Pro. (But not in that order.)

Ardupilots are just Arduino spinoffs with more I/O. There is nothing "special" on them that makes it work with a GPS.

They (the GPS) connect to an Arduino easier than a PC, just three wires if you only need to listen, four to talk to it, and don't need the USB adapter, drivers, etc. 

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Permalink Reply by Ken on May 11, 2012 at 4:20pm

Yes, it works just fine. In fact, MiniGPS even works under WINE on Mac OS. Have to create a link in your /dosdevices to point to the USB<-->TTL and good to go.

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