DShot and X8 possible with Holybro Pixhawk 6C?

Hardware Pixhawk family
1

Hello,

is the Holybro Pixhawk 6C the only Pixhawk FC that supports 8 DShot outputs?

This is what I’ve found in the documentation but I don’t trust it because the 6C is still a very new model:

The Pixhawk6C supports up to 16 PWM outputs. All 16 outputs support all normal PWM output formats. All FMU outputs (marked “FMU PWM Output”) also support DShot.

Is there really an advantage on a 6 kg heavy X8 with 15" props with DShot over traditional PWM? (except calibration)

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CUAV X7 can also do 8 dshot outputs. There might be other flight controllers that also can.

Dshot, or dronecan, of FETtec are all better than PWM because they support telemetry and that in turn allows an almost perfect dynamic notch filter.

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If you need some of those FMU outputs for something else there’s a couple of ways you can handle 8 motors

  • 8 DHSOT outputs on FMU pins, DHSOT noise immunity, all RPM/voltage/temperature data, no FMU (GPIO) outputs available for anything else, RPM, throttle or FFT based HNOTCH
  • 4 PWM and 4 DHSOT outputs, still use BLHELI32 ESCs to retain their advantages, DHSOT can give RPM/voltage/temperature data from 4 of 8 ESCs, needs ESC calibration for the PWM outputs, RPM, throttle or FFT based HNOTCH - this option is OK in a quad X8, for OctoX you would need to carefully choose motors<->outputs mapping
  • 8 PWM outputs, needs ESC calibration, still use BLHELI32 ESCs to retain their advantages (except DSHOT), all FMU outputs available, throttle or FFT based HNOTCH

I would strive to use DSHOT as much as possible because of all the extra data available, and the better noise immunity - 6kg X8 implies plenty of electrical noise and high currents. This data could be very handy for maintenance and reliability checks if you are doing any sort of heavy-lift.
HNOTCH works fine with throttle or FFT settings, so RPM data is not essential for that, but a handy possibility if you need it.

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Actually the other possibility is CAN based ESCs, or use CAN nodes to convert to PWM or DSHOT

“turn DShot capable ESCs into CAN ESCs, including full ESC telemetry”
“9x PWM outputs (8x Dshot)”

http://www.mateksys.com/?portfolio=can-l4-pwm

and if you want a bit of redundancy you could run 1 of these on each CAN bus and use 4 ESCs off each node. You would also use the Quad X8 format, and separate out 4 ESCs for top motors and 4 ESCs for bottom motors.