Blackmagic Forum

Hi Kim

I'll do more tests on this and you may be correct - that it seemed to be really picky about the values could possibly be related to the fact my sketch is perhaps a bit all over the place in terms of the frame timing - I just tried to get it to work without worrying too much about how various part of the code that process input commands might have effected sending a very regular frame timing (or - maybe I lucked out and it is pretty much in spec and I'm overestimating the code execution overhead)

I found I had to put the 2 frames that did the UP/DOWN right after each other and I used a very guessed at delay of 6ms in-between (based on the supposed spec being a frame every 14ms or so and trying to guess how long the actual frame write took at 100k baud)

certainly last night it only stated working reliably when I did use those exact values on UP especially, but I'll see if I can get it to respond reliably to a wider range

the library I linked to seems designed for a controller that sits in-between a normal sbus receiver and whatever its controlling so it can also read a signal and pass that through, etc - you would probably want to keep a lot more of it intact than I did if running with real sbus gear in the mix

oh - one other thing that I expect may be important

I had to make sure that Serial() was set to 8E2 (ie one start bit, one parity bit and two stop bits for every 8bit data byte) as well as 100k baud - a lot of what I found in terms of existing arduino code seemed to omit that

I changed the serial initialisation that lives inside the SBUS class begin() method in the library cpp file to this

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Serial.begin(BAUDRATE, SERIAL_8E2);

Kim

ran some tests and here's what I found:

for switch mode camera functions:

the range of values you can use for LOW and HIGH are quite large - it even worked if I used 800 for LOW and 1200 for HIGH

however the acceptable value for the 'base' mid point seem to be much smaller - between 1024 and 1031 it worked anything outside of those nope - eg

going from 1030 to 1200 to switch up worked
going from 1032 to 2000 didn't

same on the way down - it seems you have to define the start 'Neutral' value pretty tightly then it will accept a drop or rise of any significant amount beyond the neutral to read it as an UP or DOWN on that camera setting

this was consistent amongst any assigned camera function

hope that helps - if thats still an issue you could easily capture the 'neutral' stick position you are using and just remap it?

eg:

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STICKPOSITION = map (STICKPOSITION, 900, 1100, 1024, 1030);

should do the trick - map() doesn't truncate out of band values so you can still use anything below 900 or above 1100 as valid inputs after

I've uploaded my altered library and test sketch to git hub if anyone wants to take a look at it:

https://github.com/boldstelvis/BMC_SBUS

there will be a video to explain all later as well

Great work Stu. Sorry I somehow missed when this thread started taking off. I never got the notifications. But it looks like you've figured everything out. I've been away from playing with this for a while after having setup the gimbal controller. Hopefully getting back to it and creating a more elaborate controller/power/interface for shoulder mount setup.

cool - I'm planning something like the xc10 grip:



initial layout idea:

https://drive.google.com/file/d/0B7XMok ... sp=sharing

I'll pass along the suggestion to the teams in charge of the manual to see if that's possible.

Stu, I have the BMMCC mapped to my Taranis remote through SBUS and I cannot get these microsecond values to work correctly. for example the Rec on a 3 position switch, all it does is start recording with any input value. I have center at 1030 - UP 1200 and DOWN 0 but when I hit the switch to either position it starts recording and it does not stop even bringing it back down 0

Any one here trying it out with an RC remote?

Max

Max Buitrago wrote:Stu, I have the BMMCC mapped to my Taranis remote through SBUS and I cannot get these microsecond values to work correctly. for example the Rec on a 3 position switch, all it does is start recording with any input value. I have center at 1030 - UP 1200 and DOWN 0 but when I hit the switch to either position it starts recording and it does not stop even bringing it back down 0

Any one here trying it out with an RC remote?

Max

record works a bit differently in that any defined 'signal' will trigger on/off

in the case of sbus that would be any change from defined neutral to low or high
as I mentioned before the camera seems quite picky about what it accepts as "neutral" over sbus (in my previous tests that's strictly values between 1024 and 1030 only) which might tbe the issue?

there is apparently no defined "ON" and separate "OFF" signal for record - it will just change state each time from whatever its doing

I've been working on mine through a Taranis 9XD+ and I could only get the switch items to work if the neutral position was 1002.

I agree its kinda annoying in its current implementation.

ChrisBird wrote:I've been working on mine through a Taranis 9XD+ and I could only get the switch items to work if the neutral position was 1002.

I agree its kinda annoying in its current implementation.

After discussion with Black Magic support team even though the change notes dont indicate any changes after the version of firmware I have it appears to have resolved the issues.

Center is now considently 1514 PWM on SBUS. The doco has also been updated to explain how it works for each of the different controls. I'm very happy with it.