Mamba F405MK2 4 motor fixed wing setup

[ArMaTeC]

Hi all,

I'm trying to set up a C130 fixed-wing I'm building but I'm running into an issue when trying to add all 4 motors.
If I run with just 2 motors set the ESC powers up and I get the normal beeps from the motors but as soon as I add a 3rd the start beep sounds but the all ok beeps do not.

Does anyone have any clues on why this would happen or could anyone let me know of a good setup for a cheap 4 motor fixed-wing INAV setup.

Firmware: INAV/MAMBAF405 3.0.1 Jul 4 2021 / 13:55:23 (753c447)

Any help welcome

[stronnag]

The hardware / firmware does not support that configuration. This wiki page may assist you in selecting a board that meets your specific requirement (4 FW motors and probably 4 servos), a non-typical / non-trivial requirement.

[ArMaTeC]

So from what I can see only the KAKUTE F7 Mini V3 is the only one that support 4 fixed wing setups but that only supports a flying wing.
Unless there is anyway I can work around this I think I'm going to need to scrap this project for now or go down the pi route.

[stronnag]

There are probably a number of FCs that could support your use case (if you described it in terms of what you actually need in for number of motors and servos), some with a trivial code enhancement.

[ArMaTeC]

So I need it to have 5 servos and 4 motors

[stronnag]

If you want the FC to be able to control all of those, the MATEKH743 would be a option. It would need a small code adjustment; it provides 11 PWM outputs, with sufficient timer flexibility to meet your requirement.
(note the wiki only lists the first 8 outputs for simplicity / author laziness).

[ArMaTeC]

Ordered the flight controller I'll let ya know how I get on thank you

[stronnag]

ping me if you need help with getting it working. I'll be interested in seeing this.

[ArMaTeC]

@stronnag I have the flight controller now how would I go about assigning the 3/4 motor to the ports?

[stronnag]

It is necessary to redefine some outputs in target.c and rebuild the firmware. Note that for each distinct timer, (TIMx), there should be assigned only motor or servo, not a mix. An example is attached; 6 motors / 6 servos. Other combinations are possible, but this seems the most logical.

I've also built firmware from this target.c; also attached. Note it's from the master (development`) branch (3.1.0), as this has the most recent H743 code. You can find a contemporary 3.1.0 configurator from http://seyrsnys.myzen.co.uk/inav-configurator-next/.

Unpack the zip file, use the configurator Load firmware [local] option to load the hex file.

inav_3.1.0_MATEKH743_M6S6.zip

[ArMaTeC]

All 4 motors are working as required I will take some time to print out a new electronics box as this FC is a tad bigger and then ill get to the nitty-gritty of the servos.

Thank you kind sir you are a legend

[ArMaTeC]

@stronnag is there any way the change you did the targets.c would cause the onboard SDcard slot to stop working as the option is not there anymore and only shows serial

[stronnag]

SDcard is not yet working on MatekH743.
This is planned to be rectified prior to the final 3.1 release.