Omnibus F3 (clones, 5 different boards) Fixed Wing NO Servo signal beyond pin 4

[mickey2011]

Can someone check that there are control outputs on pins 5-8 on Fixed Wing Conventional aircraft. A Flying Wing using servo outputs 3 and 4 works OK but not for a Elevator, Aileron L, Ailron R, Rudder setup which would also use servo outputs 5 and 6.

This has been an issue from way back and still exists with the new Mixer setup in INAV vs 2.0.

My trials always use external 5 volt power supply for servos, always complete circular grounds/common.

INAV target = OMNIBUS

[shellixyz]

There is no issue with the mixer. Outputs 5 and 6 are shared with UART3. To use them you need to disable UART3 and also if you want to use the PPM input remove the S.Bus jumper.

https://github.com/iNavFlight/inav/blob/master/docs/Board%20-%20OMNIBUS.md#usage-in-a-fixed-wing

[mickey2011]

Thanks shellixyz for such a prompt answer, I've struggled with this for months, buying multiple Omnibus F3s

OK Outputs 5 and 6 are shared with UART3 and yes I have FRsky SBUS on UART3. BUT with the above setup I can drive 5 thru 8 servo's (such as a camera servo) via RC Channel 5-8 in the Mixer, they run OK from -100 to 0 but not so well from 0 to +100 and 8 is a bit different still. Can you help me get around this issue, currently UART1 is GPS, UART 2 is Frsky Smartport Tele, UART 3 is Frsky SBUS RX.

I would ditch the Telemetry, but only if I have to. Ah, how do I "disable UART 3" or do you mean ' just don't use it?

(Only GPS, not MAG)

Your help is appreciated. Thanks

[shellixyz]

You mean you have servos connected to outputs 7-8 ? Outputs 7 and 8 are not configured as such by iNav. These are shared with the I²C bus. That's the issue with this FC and it is difficult to please everybody. I²C is needed to connect a mag for MR users and the mixer doesn't take into account if the outputs 5-6 are used for UART3 or not. If you want to use 7-8 you will need to build a custom firmware.

Alternatively what you can do if you want as many PWM outputs (8?) is to use a PCA9685 I²C IO expander.

[stale[bot]]

This issue / pull request has been automatically marked as stale because it has not had any activity in 60 days. The resources of the INAV team are limited, and so we are asking for your help. This issue / pull request will be closed if no further activity occurs within two weeks.