Hi,

I am reading the CAN bus documentation (from the DJI R SDK) and I am glad that getting the current focus position and controlling focus is finally possible.

Though we can only control the focus motor, only once we calibrate the focus motor. Because the control command takes absolute values from 0 to 4095.

So, what if the focus motor is not calibrated and A and B points are not set? (how it often happens with lenses without hard focusing stops, i.e. Sigma ART).
The existing control command does absolutely nothing.

I am proposing to add a new command:

- It would basically be a copy of the "2.3.4.19 Focus Motor Control Command", but instead of "Absolute position" we need to provide "Relative position" in the number of steps of the stepper motor. If the number is negative - motor moves in the oposite direction. The main point is that it should work even if AB points are not set. In case if the AB points are set, it will still work, just would be limited by AB. And also it should be very similar to how the focus wheel works (the focus wheel still works even if AB points are not set).

And of course, the "Command sub ID" would be different, for example 16.

Motivation:
- allows to use the focus motor without calibration.
- it would help in setting AB points programmatically.

Because if we read that quate from the docs:

Note: To set the calibration range manually, rotate the Focus Motor to a fixed position, send the
calibration command 0x04 to set the minimum calibration range, rotate the motor to the next
position, send the calibration command 0x05 to set the maximum calibration range, and then
send the calibration command 0x02 to enable manual calibration.

We can see that there is no way to "rotate the Focus Motor to a fixed position" programmatically, only by hand.

I also checked sbus and it seams there is no channel for the focus motor in sbus. It could be added, though using both SBUS and CAN-bus is not possible just by interfacing the pins in the focusing wheel (there is a switch, so only one bus is visible at a time).

+1 for that,

Did you manage to get the Focus Motor 2022 version working using the SDK ?

Where do we get info on this DJI R SDK?