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MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Sun Dec 23, 2018 8:05 pm
by miky94
I'm using a Raspberry to control a MultiWii Flight Controller V2.5 by using this https://it.aliexpress.com/item/FTDI-Basic-Breakout-USB-TTL-6-PIN-5V-Module-Fio-Pro-RGB-Lilypad-Program-Downloader-For/32709195540.html?af=20181224clvjfsptoph0&aff_platform=promotion&cpt=1545591759487&sk=jiMVVzv&aff_trace_key=fa773ca751ec4af092f943ea43f7d643-1545591759487-00174-jiMVVzv&terminal_id=a6bf17170756425fbe698911338e3cd7 FTDI USB to TTL adapter.
I've seen in this https://www.instructables.com/id/Ultimate-Intelligent-Fully-Automatic-Drone-Robot-w/#step23 instructable they instead use just a cable from Raspberry TX to MultiWii RX, but I'm not sure they have the same voltage because the Raspberry logic-level is 3.3v and I didn't found clarifying informations on if the MultiWii logic-level is 5v or 3.3v.
I'd like to eliminate the FTDI and use just the cable for reducing space and weight.
is the connection in the image right?
Image

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Mon Dec 24, 2018 1:12 pm
by PatrikE
Hi,

The Multiwii boards with Atmega 328 usually have 5V logic level.
You need a level converter to protect the PI if it don't handle 5V.
Logic Level Convert can be found everywhere on Ebay etc ( Logic Level Converter Module Bi-Directional for Arduino 5V-3V )


/Patrik

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Thu Dec 27, 2018 12:39 pm
by miky94
PatrikE wrote:Hi,

The Multiwii boards with Atmega 328 usually have 5V logic level.
You need a level converter to protect the PI if it don't handle 5V.
Logic Level Convert can be found everywhere on Ebay etc ( Logic Level Converter Module Bi-Directional for Arduino 5V-3V )


/Patrik


and what about the link on instructables.com?

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Thu Dec 27, 2018 3:34 pm
by PatrikE
Looks like PI is only connected to RX on MWIi board.
Then it will probably work fine.

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Thu Dec 27, 2018 7:01 pm
by miky94
PatrikE wrote:Looks like PI is only connected to RX on MWIi board.
Then it will probably work fine.


yes but I'd like to be sure because it was really hard to find this FC , is not there a detailed datasheet?

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Thu Dec 27, 2018 9:04 pm
by PatrikE
It's hard to find documentation on old boards.
And there's almost 70 different Predefined FC with support for MWii in latest release of MWii.
Most MWii boards are no longer in stock.
It will work with any of these FC's.(Preferably with Atmega 2560 )

But it will also work with iNav on 32bit FC

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Tue Jan 08, 2019 11:25 am
by miky94
therefore I'm looking for a new FC with these specs:
- cheap
- MSP compatible
- best hovering (immobile, for stable video) and precision of maneuverability
- with GPS functions
can you suggest me one or some (with pros and cons)?
Thanks

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Wed Jan 09, 2019 9:43 pm
by PatrikE
HI,

Sadly MWii flight controllers is getting hard to find now.
I would suggest to get a 32bit FC.
ex.
https://www.banggood.com/Betaflight-F4- ... rehouse=CN


It comes preloaded with Betaflight.
It will also run iNav if you want to test.
Both use MSP on serial port.
iNav have navigation.
I'm not sure about Betaflight,Last i checked it just had simple GPS functions.(RTH etc)

But there's many other options with F3 and F4 processors.

Good luck
//Patrik

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Mon Jan 14, 2019 10:37 pm
by miky94
thank you , it will probably be my next upgrade.
another question, can I connect my MultiWii FC to this TGY-IA6C receiver and how?

Re: MultiWii SE V2.5 logic voltage is 3.3v?

Posted: Tue Jan 15, 2019 8:16 am
by PatrikE
Connect PPM from RX to [ -,+,D2] on the FC.
In Config Enable

Code: Select all

#define SERIAL_SUM_PPM         ROLL,PITCH,THROTTLE,YAW,AUX1,AUX2,AUX3,AUX4,8,9,10,11 //For Robe/Hitec/Futaba
#define PPM_ON_THROTTLE         // D2 on MultiWii SE V2.5

FC.PNG

Then it should work

//Patrik