So we can only map the input to a channel one at a time and only in pairs
The channel described here is the Timer Channel, above you talked about the DMA channel
> You need one DMA channel per timer pair
Am I missing something?
TI1 and TI2 are the trigger inputs - these have limited DMA mappings
Apologies. Iām afraid I donāt have time to revisit all of this - @bugobliterator may be able to provide some context as he worked on this too, but he is also very busy.
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From memory, each timer channel can only have two trigger inputs, which is the reason we can only cycle DMA channels (and the attached peripherals) between pairs of outputs. You obviously can use more DMA channels than this, but they are at a premium.
So turns out the default firmware for the Pixhawk 2.4.8 supports Dshot on six channels but not bi-directional Dshot. You can get RPM from a serial port and use that to drive the notch filters. I got it to work on copter 4.0.5.
I think we build the bdshot version now
We strongly advise you to update .
There have been many dshot improvements in the recent releases
I found Copter-4.1 and above to be unstable on large drones or possibly just my drone. Is Dshot unstable on 4.0.5? Should I use PWM instead when using that version?
Oddly it looks like Pixhawk1-1M only not the Pixhawk1 version one would use for those 2.4.8ās.
Iām just finishing my first Dshot ESC installation.
Iāve been trying to find out if the issue with the Orange Cube and Dshot pass-through has been resolved yet. Can someone on this thread offer some information or guidance?
Also - if the issue isnāt resolved, is there any problem using Aux2-Aux5 on a quad? I just wondering because Aux5 is normally used as a relay.
Many thanks.
You must use aux1-aux4. DShot is grouped in groups of 4.
As I see it (donāt have any Cubes) with the standard Cube Orange firmware if you configure Aux 2-5 for Dshot then all Aux outputs will have to be Dhsot due to the timing groups:
The better option is usually to use the Bdshot version of firmware as a better reference to drive the Notch Filter. But, thatās a different situation:
Presumably Aux 1,3,5&6. But you still wonāt have passthru on Aux 1.
The PR seems to indicate itās a hardware problem that wonāt be fixed with a firmware solution.
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2 through 5 - isnāt that a group of 4?
And are you saying that Dshot canāt be used on a tri-copter?
The groups are not variable - its a fixed mapping of output to timer
Interesting - many thanks.
What groups of 4 are allowed?
More to the point - for someone building a new quad-copter using Dshot - what Aux ports are allowed?
Depends on the Flight Controller. Some have all āAuxā ports as they donāt have an IOMCU.
For example, on a Matek H743 all of these can be Dshot. If you need to mix outputs to servos or GPIO just respect the timing groups.
Of course.
Iām using an Orange Cube - which is the only one Iāve heard has a problem with Passthrough on Aux-1.
The reason for my inquiry is that Iād like to give RPM based harmonic notch filter processing a try. I havenāt found out if the passthrough problem on the Orange Cubeās AUX-1 will prevent that.
I guess thatās why Iād like to know if I can use different AUX ports.