MultiWii Pro AIO and NEO-6M GPS

[iWolf51]

I have the HK V2.0 of the MultiWii AIO board which I think is equivalent to the CRIUS V1.1 of the board?
I think I read that somewhere hereabouts...
I also have the HK version of the NEO-6M GPS plugged into the board.
The FC is running MultiWii V2.2.

A couple of things about the setup are puzzling me (no surprises there  )
Its all very new to me at present and I';m trying to understand the meaning of the FC leds when the board gets power.
Because they seem to be at least a bit different than those posted on forum.
At power up:
- the A and C leds flash a couple of times then stop while the ESC initialises.
- then the A and C leds flash quickly for a few seconds and go out again.
- at the same time the B led flashes, in what seems to be a variable sequence.
When the motors are armed:
- the A and C leds light solid.

The interesting thing is the B led, which will continue flashing, sometimes in a steady sequence, other times in a changing sequence.
On occasions it will even go out as well.
Is this to do with the number of sats found, or GPS lock?
If I connect the board to MultiWiiConf it shows GPS co-ordinates and a number of satellites.

Related to the GPS, the HK board supposedly ships with baud rate set to 38400.
I';ve loaded sketches to the FC with GPS baud rate set to 38400, 57500 and 115200.
The setting doesn';t seem to make any difference to the FC, can this be right?
I thought the baud rate on the GPS and in the FC firmware would need to match?
Is there any performance advantage in using a particular baud rate?
I haven';t got an FTDI cable (yet) so can';t connect the GPS to u-center to check the actual GPS config.
I haven';t yet had a chance to try a GPS home or hold command to test the GPS in the field.

Anyone able to help with this?

[Hands0n]

You absolutely have to match the serial speed of the GPS with the FC, it cannot work otherwise. 

Things to check with the GPS should include what GPS signalling is it using?  NMEA is the standard - there are also uBloc';s own protocols. I think by default the GPS puts out NMEA so make sure that your MultiWii sketch is set for that.

I have the Crius AIOP 1.1 and when there is a 3D GPS lock the green light on the FC goes solid and stays that way.

I';m using MegaPirates NG Add-Ons so it is a little bit different for me, and I have no direct experience of the HK iteration of the FC.

HTH

[iWolf51]

You absolutely have to match the serial speed of the GPS with the FC, it cannot work otherwise. 

Things to check with the GPS should include what GPS signalling is it using?  NMEA is the standard - there are also uBloc';s own protocols. I think by default the GPS puts out NMEA so make sure that your MultiWii sketch is set for that.

I have the Crius AIOP 1.1 and when there is a 3D GPS lock the green light on the FC goes solid and stays that way.

I';m using MegaPirates NG Add-Ons so it is a little bit different for me, and I have no direct experience of the HK iteration of the FC.

HTH

Thanks for the feedback mate.

I made some interesting discoveries today, while getting my FC and GPS talking to each other.
Behaviour/operation of the FC and GPS was observed over several rounds of firmware changes and FC testing.

- MultiWii V2.2 has the following definition in config.h which changes the operation of the GPS indicator LED on the FC.

/* indicate a valid GPS fix with at least 5 satellites by flashing the LED  - Modified by MIS - Using stable LED (YELLOW on CRIUS AIO) led work as sat number indicator
      - No GPS FIX -> LED blink at speed of incoming GPS frames
      - Fix and sat no. bellow 5 -> LED off
      - Fix and sat no. >= 5 -> LED blinks, one blink for 5 sat, two blinks for 6 sat, three for 7 ... */
    #define GPS_LED_INDICATOR

On my HK V2.0 FC, when the define statement is active the GPS indicator LED operates as in the quoted comment above.
With the define statement commented out, the LED flashes while acquiring a lock. When GPS lock is acquired the LED goes solid and stays that way.

I can also confirm that I am able to get a GPS lock with GPS_BAUD set to 38400, 57600 or 115200 in config.h.
Since baud rate between the GPS and FC has to match for comms to happen there must be something in the MultiiWii code or GPS firmware to force a match between the two components. I';m curious about that so I';ll investigate it when I get time.
In the meantime I';m satisfied that I have GPS comms to the FC and can test if GPS HOME will work.

Also the 3 indicator LEDs on the FC operate differently than on the CRIUS board (Using Jumpy07';s table for the CRIUS board) at least they do on my FC.
As per the OP, LEDs A (Orange) and C (Green) flash while the board is initialising, then turn off. They both come on solid and stay on when the motors are armed.
Operation of LED B (Orange) depends on the setting of  GPS_LED_INDICATOR.

So a couple of things are a bit clearer and I can test operation of the GPS.
Now to get the Bluetooth module working.
Edit: How hard was that!
- Plugged the bluetooth module into the FC
- paired it with my mobile
- started the mobile app and went through config
- App and FC connected - and it worked  ::)
- WoooHooo!

[iWolf51]

Just a quick update regarding setup of the NEO-6M GPS with MultiWii 2.2.

We were discussing GPS config in previous posts ^^.  I was surprised, make that confused, that the GPS seemed to be synching with AIO Pro regardless of the GPS baud rate set up in config.h

I';ve now found the reason it works 
We can thank the MultiWii development team for a change in MWC2.2, that makes setup that little bit easier. Maybe they';ll update the comments in config.h to match at some stage.

UBLOX GPS: the baud configuration is autodetected and the UBLOX binary protocol is automaticly set (thanks to MIS & EOSBandi)

Heres a link to the release notes http://www.multiwii.com/forum/viewtopic.php?f=8&t=3212&hilit=led+pin

[barneyg]

Yep ... It starts at 9600 and steps up the speed till it can communicate then it sends a config string which includes the speed you specify in the config.h .... Use the 56 k option - apparently 112 k introduces an error in the position supplied

[cliffkhew]

Multiwii v2.2 will set the NEO-6M GPS module auomatically to 115200Hz,how about the refresh rate?Will it set to 5Hz?

[Hands0n]

Multiwii v2.2 will set the NEO-6M GPS module auomatically to 115200Hz,how about the refresh rate?Will it set to 5Hz?

The FC';s serial speed for the GPS port can be set in config.h for MultiWii (and in the MegapiratesNG config file also - I forget its name). There really is no need for the speed to be above 56kbps, the amount of data being sent is miniscule.