How to wire up the MadFlight FC3V1 (Rpi) to a 4-in-1 ESC with DShot motor control (preferably bidirectional)?

[KernelKlinq]

I am currently trying to bring up a new aircraft with a MadFlight FC3V1 flight controller.

I can get out.setupMotors to work with the following code:

bool success = out.setupMotors(4, motor_idxs, motor_pins, 400, 950, 2000);

However, I cannot get the DShot options to work by uncommenting one of either of the following code lines:

//bool success = out.setupDshot(4, motor_idxs, motor_pins, 300); // Dshot300 without telemetry //bool success = out.setupDshotBidir(4, motor_idxs, motor_pins, 300); // Dshot300 Bi-Directional

I know the ESC supports DShot. ESC is a Lumenier Siege 55A NDAA 4 in 1. I can see its configuration and change it via connection through another FC and the AM32 configuration tools (web and standalone).

Any suggestions for software troubleshooting or hardware wiring are appreciated very much. Thank you!

[KernelKlinq]

Also, additional information, I am using the Arduino IDE to program the FCV3.

My reason for wanting to use DShot is that I think it is needed for the motors to eventually be set up for bidirectional operation. I want these motors to be able to push or pull.

[qqqlab]

Hi @KernelKlinq by coincidence I was working exactly on this topic today, and pushed an update which fixes dshot and bidir dshot. (Note: bidir refers to telemetry here, not to bidirectional motor operation.)

To try it out, clone or download this repository and unpack it in your arduino libraries folder (i.e. overwrite the existing libraries/madflight folder) After compiling you should see v2.2.2-DEV as version number.

[KernelKlinq]

@qqqlab ,

I would be happy to "sponsor" you to obtain a hardware AM32 DShot / DShot 3D (a.k.a. DShot "reversible") 4-in-1 ESC if that would help. For some larger stuff, it seems like BLHeli_S might eventually go away, and I would like the option to use USA-friendly ESCs (NDAA, etc.) in my build. Is there a good way to send you some funds....?

[KernelKlinq]

Also, with the AM32 ESC, the error I get is at the initialization stage, if that helps...

if(!dshot_impl.begin(pins[0], cnt, freq_khz)) {
  Serial.printf("OUT: ERROR dshot init failed");
  return false;
}

[qqqlab]

The problem appears to be an issue with claiming free PIO state machines.

If you disable the RGB LED and/or the SDCARD the above demo program will work. Simply put

bbx_gizmo NONE
led_gizmo NONE

at the end of your madflight_config string in madflight_config.h

[KernelKlinq]

@qqqlab, thank you so much for your work on DShot and on this entire project.

I can confirm that the AM32 ESC DShot appears to be working, and even in a very "weird" configuration I am trying to use. I am still able to use the LED gizmo on the FC3v1 FC, but did disable the BBX gizmo. I have the ESCs set up with two standard non-reversing motors (unidirectional) but one is reversed at the ESC level (to get the wiring pattern I wanted). Two other motors, with different KV and pole count settings, are configured as DShot reversible, and also appear to be working well. The telemetry also appears to be putting out accurate RPM (bidirectional DShot), but for the reversible motors, it doesn't know the difference between clockwise and ccw RPMs (but that can be solved in software).

I have a really strange airframe that I will be trying to fly soon, and if it doesn't fly well now, I am sure I can get it to fly with just a few more hardware tweaks now that the control firmware is close to working.

Thanks again!

[qqqlab]

Thanks for the feedback!

I've added a patch (but still work in progress), now also BBX should work. Some logging might be handy to log your first flights :-)