Lintz

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Re: Gyro Sync and Low Latency?
« Reply #15 on: February 22, 2016, 12:35:00 pm »
I have been looking at the Revo for a while now but since I'm building a 250 racer it have felt a bit "too much". How would it be to keep around the cc3d as a barebone racing fc much like the naze32 6dof or kiss fc. And then the revo for every thing else? What i mean is stripping the cc3d of every thing gps and non race stuff?
May the quad be with you.

hwh

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Re: what´s the deal with Betaflight and Raceflight?
« Reply #16 on: February 22, 2016, 03:10:04 pm »
...CC3D is hindering development for the Revo and the Sparky2.  There must have been a lot of man hours invested in bringing support back to the CC3D and a lot more in trying to make any new change fit inside of it.

I for one would agree if the CC3D was left behind.

It doesn't really hinder development for other boards, it's just that new features can't be added to it.

I don't think there's any chance that cc3d support will be discontinued, part of the reason LP was formed was to add back the cc3d support.

lucas

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Re: Gyro Sync and Low Latency?
« Reply #17 on: February 22, 2016, 06:45:05 pm »
I have been looking at the Revo for a while now but since I'm building a 250 racer it have felt a bit "too much". How would it be to keep around the cc3d as a barebone racing fc much like the naze32 6dof or kiss fc. And then the revo for every thing else? What i mean is stripping the cc3d of every thing gps and non race stuff?

It doesn't really hinder development for other boards, it's just that new features can't be added to it.

I don't think there's any chance that cc3d support will be discontinued, part of the reason LP was formed was to add back the cc3d support.

If I understand correctly that´s the "modularity" that TheOtherCliff is talking about...  You can´t just add whatever new feature to the Revo or the Sparky2, let alone the Ground Control Station, and expect the CC3D will run without a problem.

hwh

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Re: Gyro Sync and Low Latency?
« Reply #18 on: February 22, 2016, 07:53:21 pm »
If I understand correctly that´s the "modularity" that TheOtherCliff is talking about...  You can´t just add whatever new feature to the Revo or the Sparky2, let alone the Ground Control Station, and expect the CC3D will run without a problem.

You can add new features to the Revo and Sparky2 without affecting the cc3d, that's not really a problem.  If it was we wouldn't have all the advanced modes that only run on the revo/sparky2.

I don't speak for Cliff but what I think he was talking about was rewriting the code to allow disabling and enabling parts of the cc3d code through the gcs configuration page.  For example, if the cc3d could only run 3 of 4 flight modes you wanted in it at a time you could pick which 3 were enabled through the gcs.  This would be a lot of work to implement and would only work for relatively small additions, something like the gps and flight planning modes would still probably never work.

cato

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Re: Gyro Sync and Low Latency?
« Reply #19 on: April 17, 2016, 03:03:16 pm »
I have several cc3d and an atom lying around here. I bought them because I simply love that FC. But at some point I had to say good bye, as the Revo controller is simply a lot better, and now it is easy to get as a clone.

I think that the CC3D has it's place especially with racing quadcopters and easy, simple setup. It performs so well there. But actually I am flying the revo now on both quads, and testing the sparky2 is on my plan as well. Those controllers are simply better than a CC3D.
Nighthawk 250, MT1806, 12A ESC OneShot125, Revo, M8n GPS, FPV
Cinetank MKII, Elite 2216, 30A Afro OneShot125, Revo Clone, M8N GPS

vv

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Re: Gyro Sync and Low Latency?
« Reply #20 on: April 17, 2016, 10:18:19 pm »
Hi guys, I am new to the forum and CC3D but not new in programming stabilization stuff.. I don't know if you realized, but I am desperately trying to get debugging working on my machine so I can start working on exactly that, lag, latency, whatever you call it. I think i know where the problem is but I haven't been able confirm any, cos I can't get the damn thing to debug..

Anyway I realized there is a lot, like between 0.1 and 0.4 secs of lag, which is unacceptable for my flying. The thing is that the lag is also in manual mode (I fly planes) which is bad! I know the processor is more then capable of crunching all the data, at an acceptional rate that is. This brings me to my point. I've been browsing the code and found this little comment
Code: [Select]
/**
 * WARNING! This callback executes with critical flight control priority every
 * time a gyroscope update happens do NOT put any time consuming calculations
 * in this loop unless they really have to execute with every gyro update
 */

So how often is gyro updated? I know this can be crazy fast. Back in the days just when heli gyros came out and I started programming stabilization for my RC planes from scratch (now I am trying to port some the code here) I was (still am) processing gyro (main) cycle at 30Hz and I had the stablest plane around. There is no need to process any more often, it just doesn't make it any better. Use 50Hz at max, thats the rate servos are updated but highly doubt it would make any diff. Set the task priority at 30Hz and read the gyro data at the biginning of the cycle. Thats what I am trying to do but I can't get the thing to debug. Anyway, if anyone wants to help me out with it find my recent posts :)

So what is the update rate of the gyros?

Hope this is helpful info..

Cheers!