BMMCC remote Control via S.BUS/PWM/LANC and some issues

Hello,

I got a BMMCC last week and started to test the various remote control options. After all, I found a way control every feature, but there seems no way to use only one way. Here are my preliminary results of the testing and I hope for other people to comment on this in ways like "same here" or even "works for me, i did this or that".

Rec Start/Stop:
LANC: 1833 toggles recording, no response to the stop command 8C19
PWM: Switch On/Off to GND works fine, PWM just to start recording!
S.BUS: Only start... sometimes.

IRIS:
LANC: 2853 close/ 2855 open / 28AF Auto
PWM: PWM working fine, no steps via pushbutton
S.BUS: works fine

Focus:
LANC: no (visible) response to 2845/2847, only Autofocus at 2843
PWM: PWM working fine, no steps via pushbutton
S.BUS: works fine

Zoom (Oly 12-50mm):
LANC: 28E1 steps to wide/ 280E steps to tele (fastest modes, others working as well)
PWM: only full in/out, same with pushbutton
S.BUS: only full in/out

ISO/Shutter Angle/WhiteBalance:
LANC: nothing
PWM: (more or less) random/no response to PWM/ pushbutton works fine to step/cycle through
S.BUS: (more or less) random/no rsponse

I'm a bit disapointed that there is no official documentation of the several interfaces apart from the pin-outs given in the handbook.
A complete list of supported LANC commands and what reactions can be expected from the PWM and S.BUS signals would be very helpful.

I really wonder how other remotes (e.g. onelittleremote) are interfaced. Only LANC oder others as well? Unfortunately I can't find a manual for this to peek for the required camera settings

Why is proper zoom control only possible via LANC and not via PWM/S.BUS as mentioned on the Homepage?!

Why do I not see any reaction to LANC Focus control, even after sending it many times?!

SBus, will control al, the remote functions available on the Micro cameras, I have tested this.
You get very good control over:
Start/stop (Micro Cinema only)
Iris, can be up/down step,control via toggle switch, or controlled smoothly (depending on the lens) via pot
SA toggle up or down through the values
WB toggle up or down through the values
Zoom (on MFT PZ/PE zooms only) same as Iris, pot control works best, but can be toggle controlled also
Focus same as Iris, I have it in the Pot co tool for smooth focus pulls with nice FF type control

The SBus needs a micro controller like the Arduino to get the correct values sent. This is how Kim L. and Phil's SBus remotes work.

PWM is either via a radio receiver/transmitter, or momentarily shorting the signal to ground to toggle the value one direction only.

LANC as you found out, inlyma few shooting controls available, depending on the LANC controller, you can get zoom with MFT Power zoom lenses, focus, but is slow with lag on my Bebob controller, the BM Ursa Mini handle will give Push to focus feature (LANC is the only way to get this feature, which is how Phil is doing it, using both LANC and SBus together), and push to set instant Iris/f/stop to prevent sensor clipping on brightest area.

So as you said, not all functions available on any one method, but LANC combined with SBus gives all the combos, using the SBus for most, and LANC for instant focus/Iris (Push to focus, etc) controls.

Again, the lens focus and Iris controls only work with MFT native auto lenses (not all of the early lenses will work, and nor do the adapted Four Thirds lenses work with LANC control.
Cheers

Thanks, Denny!
Great to hear that it is possible to control most of the settings via one protocol.

I did a relatively quick test with the S.BUS. I used a microcontroller and a potentiometer to send values between 0 and 2048 to the different S.BUS channels. It is working perfectly for some things like Focus and Iris, but not for others like the Zoom. That is something I really don't understand as the Zoom is working (in steps) using the LANC interface. Via S.BUS and PWM it is only full far/close above a distinct value.

My Lens is a new M.ZUIKO 12-50mm ED and is for sure abled to zoom remotely as I already did via LANC.

That S.BUS is working for some things makes me think that my general implementation of the protocol is correct. But even if I switch the channels in the remote menu of the BMMCC, it does not work for all features.

How does a Switch/Pushbutton Command via S.BUS look like? Is it like 0/1 or 0/2048? How do I control rec/stop correctly? I was just abled to start "somehow" but it never stopped.

How can I make the Camera toggle through the values using S.BUS?

Many Thanks!

Gabriel, you need to ask Kim this, as I only test the remotes, I do not build or design them. You can get his PM on the other BMMCC Remote thread on the Cinematography Forum here.
Cheers