Replies to This Discussion

Permalink Reply by u4eake on October 29, 2012 at 3:06pm

The 3DR mediatek gps has it's own firmware I believe.  If I recall correctly it's in binary mode and at 115200 baud.

http://code.google.com/p/ardupilot/wiki/MediaTek

I have also been eyeballing the crius all-in-one.  Seems it has sensors that are just as good as the apm2.5, but at a cheaper price + it can also run multiwii.

Any idea how flightperformance and stability compare to the apm ?

Thx !

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Permalink Reply by Christoph on October 29, 2012 at 3:54pm

Thanks for your help! Is there any way I can use this mode then within megapirate?

I've tried GPS_PROTOCOL_AUTO and _MTK16 with baud rate 115200. I've also enabled GPS Lock in the settings but the screen still says NO GPS.

If I run the test in the console, I'm getting repeated 'garbage' lines, I guess this might be the binary protocol the GPS is sending?

Regarding your question: I cannot compare it to the APM, I only have a KK2 and its ancestor.

There are however some videos on youtube showing it performs quite well, which is also my experience. The only thing I noticed is that in Acro mode it seems to be more difficult to fly than the other boards, but I think this depends on arducopter and my current settings. I've tested the stability and alt hold mode (with non flashed ESCs) and it performed also really good.

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Permalink Reply by Para on October 29, 2012 at 4:12pm

Cristoph, posting in more forums won't help your issue. Get a FTDI interface, get the GPS hooked up to the PC and check its settings.

Otherwise, your options are to reload the AIOP firmware with all possible serial speeds starting at 9600 and with either NMEA or MK16 for protocol and see if you get any result.

@u4eake: the AIOP is OK if you need a 2nd (or 3rd or 4th) FC to test different frames and setups without dismantling the APM from its current frame. Works with the cheap hc-sr04 sonar. But if you don't fancy delving deep into code, you'll have to wait for MPNG ports from current AC releases. Latest is based on either 2.6.x or some beta 2.7, can't tell exactly which.

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Permalink Reply by John Grouse on October 29, 2012 at 9:07pm

Even though I am using the MultiWiiCopter Paris board, you could still hook up MultiWiiCopter's I2C GPS/Mag board to it and then use an OSD which reads the MultiWii serial protocol.  I'm using the Rushduino OSD which connects to the serial port of the Paris MultiWii board.  No need for separate GPS's for the MultiWii GPS functions and the OSD positional feedback.

Using MultiWii V2.1 this gives me pos hold and RTH as well as a fairly comprehensive OSD with arrows and distance to home.

You may need to disable the mag on either the MultiWiiCopter I2C_GPS or the CIRUS board.

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Permalink Reply by Andrew Radford on October 29, 2012 at 11:46pm

use:

#define SERIAL2_BAUD 38400 // GPS port

and

#define GPS_PROTOCOL GPS_PROTOCOL_MTK16

The GPS supports 115K and binary, but will start up in 38400 NMEA, then there are some special commands to put it in binary mode.

This all assumes you have the same firmware on the GPS. To check this, get the 'MTK firmware tools', which allows you to change the firmware, and tweak the GPS etc, You can then confirm what the baud actually is on your PC. I'm not sure where the official source is for this but you can get them here.

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Permalink Reply by Christoph on October 30, 2012 at 6:06am

Thanks for your answers!

Para, I've asked here because after digging around I found that this board is more suitable for the particular question as it is not related to the board but the software.

Andrew, I'll try that, thanks a lot!

I don't have a FTDI cable right now, but I'm currently ordering from rctimer. I wondered if this board:

http://www.rctimer.com/index.php?gOo=goods_details.dwt&goodsid=...

Is the same as a FTDI cable and let's me connect to the device? I never used/had an FTDI cable

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Permalink Reply by Para on October 30, 2012 at 7:02am

You don't have to wait for a package to arrive from HK for thigs as trivial as FTDI or ASP interfaces. They are found in alot of diy electronics stores and in everything connected to robotics and arduino.

Granted, an FTDI is $7 in HK and you'd probably find it for $20 in a store near your place, but it's mostly a one-time purchase and it's useful in a lot of applications. You can connect with it to GPS units, 3DRadio units and FrSky receivers, just to name a few.

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Permalink Reply by Christoph on October 31, 2012 at 1:59pm

I'm in Austria, and to be honest I can't find anything like an FTDI cable close - maybe I don't know the right term in German though ..

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Permalink Reply by Para on October 31, 2012 at 2:24pm

http://www.physicalcomputing.at/shop/article_A-1105500/USB-Serial-A...

 

I've only had to google "arduino shop austria" and it was the third link it returned.

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Permalink Reply by Christoph on October 31, 2012 at 2:48pm

Thanks for the hint

It's a bit difficult to find out what you 're looking for if you never had anything to do with arduinos at all... I have no idea what a breakout board is :)

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Permalink Reply by Christoph on October 31, 2012 at 1:58pm

Thanks for the hint, however, I still have "No GPS" - what am I supposed to see if I go to Terminal -> test -> gps?

Do I have to issue these commands in the terminal?

I suppose I again need the FTDI cable for these firmware checks..

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