Unable to get DSHOT to work with PixRacer

I have read through several posts regarding the implementation of DSHOT and I have it working on my Pixhawk 4 mini but for some reason I can’t get it to work on my PixRacers running the latest release of ArduCopter ChiBios. Is there anything special I have to do to get them to work with the BLHeli ESCs that I know support all flavors of DSHOT?

@TTGold Pixracer has no aux ports, so wiring is same as regular ESC, as noted here.
However you need to set the parameters related t DShot.
HTH,
Gal

I thought I followed this setup… I guess maybe something I missed was setting the SERVO_BLH_OTYPE to Dshot. Initially I only set MOT_PWM_TYPE to Dshot. Do I need to set both in the PixRacer?

Edit: - I read through the config again and I don’t see how the PixRacer would need the SERVO_BLH_OTYPE type set to Dshot as the PWM pins are not aux pins. If anyone can provide more information on a successful working config for PixRacer and Dshot that would be great… Also I know that BLHeli32 is the only protocol allowed for passthrough. Does this mean that only BLHeli 32 ESCs are supported? If so then this is my problem. I have BLHeli32 with my Pixhawk 4 and non 32 BLheli with my pixracers…

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That could indeed be the problem. I have some older BLHeli-S ESC’s with a Pixracer and they don’t work with Dshot but it’s not clear they should. Are the ESC’s you have supposed to support Dshot?

All the ESCs that I am using with PixRacers are Hobbywing BLHeli and all support Dshot. Not all are BLHeli32 though…

The BLheli suite software is specific to BLheli32, Blhelis or blheli16, you must use the matching software.
My understanding is that blheli 32 is the only one that will work with Ardupilot.

I understand that passthrough blheli ESC management is specific to 32 in ardupilot, but it does not specifically say that the DSHOT protocol only works with 32. I am not talking about passthrough I am talking about DSHOT_150 to BLHELI DSHOT (not 32) ESCs. Not management of the BSCs via passthrough.

I don’t know why this wouldn’t work unless there is something specific about Hobbywing Dshot. Just for kicks did you try to set the Mask for chan 1-4 and the Otype to Dshot? I realize the purpose of these is to set other than standard motor group output but…

I think I will give this a try next to see if this works. Thanks for the suggestion…

Hi
I’m having the same problem.
Running my quadcopter with a Pixracer flashed with APM 4.0.3 connected via the servo pins to a Racestar Rev35A 4in1 ESC.

Racestar 4in1 ESC is a BLHeli-s and not a BLHeli32 ESC. I did flash it using BLHeli suite while connected to a different flight controller using Betaflight pass through to verify the ESC is correctly configured.

Set parm “SERVO_BLH_OTYPE to DSHOT150” in QGroundControl.
I connected the only the 4 servo pins and ground pin from my 4in1 ESC (Didn’t connect the VBAT to the VDD pins on the Pixracer)

I can’t get the motors to spin at all.
Any help will be highly appreciated.
Eliav

It won’t work with BLHeli_S. Been there, done that, will give away the Tshirt :grinning: Set it to Oneshot125.

BTW-Not that it matters but it was also with a PixRacer.

Greetings Dave,
Appreciate your prompt response.

Wanted to update that I was able to get the Pixracer to work with the BLHELI-S ESC.
The setup is similar to what I described in my previous post.
After loading the latest BLHELI FW to the ESC using an old FC with BetaFlight pass-through and setting the APM to use D-SHOT 150 seems all is working.
FYI

Hi Eliav-Interesting, I’ll check that out. I previously tried Dshot on 2 different craft with PixRacers and BKHeli-S ESC’s and the motors just stuttered. I look at it again.

Good luck
Stay Healthy :smile: