# PC control protocol

COM port setup: 8N1, minimum baudrate of 115200, higher can be better

## Reporting
Board periodically sends info about lens in below format:
```
Focus mode: MF Focus limit: NO Focus: 16388 Focal length: 27.999964 Aperture: 4884
```
### Focus mode:
Values:
  * MF - manual focus
  * AF - autofocus (manual focus ring is disabled in this mode)

### Focus limit:
Values:
  * NO - focus element is not in any limit position
  * NEAR - focus element is in far limit position
  * FAR - focus element is in near limit position
  * UNKNOWN - another unknown value, it shows after far, so I suspect parking position

### Focus:
  * Raw data from lens indicating focus position in steps

### Focal length:
  * Computed from raw data

### Aperture:
  * Raw data from lens

## Control
Messages which control the lens from PC, they are **not** case sensitive
### Focus mode:
For autofocus: `af`<br>
For manual focus: `mf`

### Aperture:
You can send either absolute value corresponding to what lens returns or relative value.<br>
For absolute: `aperture 5678`<br>
For relative: `aperture_rel 100` or `-100` depending if you want to open or close it

### Focus:
You can send either absolute value corresponding to what lens returns or relative value.<br>
For absolute: `focus 18000`<br>
For relative: `focus_rel 100` or `-100` depending in which direction you want to focus

### Zoom:
Zoom is a bit different in that it is controlled externally with stepper motor so the commands are a bit different. You can zoom on specific focal length or by count of steps. There are not set software limits to where you can zoom, so make sure, that you have some kind of protection setup either mechanical or in stepper controller setup with for example top current limit.<br>
For zoom at focal length: `zoom 100 50` where first number is focal length and second one is number of steps per iteration, smaller number = better resolution.<br>
For steps mode: `zoom 0 200` where first number is direction: 0 retract, 1 extend, and second is number of steps.<br>

Zoom speed can be set in file on the board, when connected to PC and with open Thonny IDE, you can select interpreter in bottom right corner to MicroPython (RP2040) and after that in left panel open config.py and edit `ZOOM_SPEED`<br>

If lens zooms backwards, flip stepper motor connector. **MAKE SURE, THAT BOARD IS POWERED OFF**