v4l2-ctl-KlipperFocus

I had tried to get my LMX179 USB webcam to set a manual focus level using the crowsnest.cfg file but it never seemed to work. Manually sending a value in the command shell did work, so I set about making a way that would automagically apply a focus value after Klipper starts up.

Essentially, this is just a "fancy" way of getting Klipper to manually send a command once it's up and running. Also as a bonus, it lets you send focus adjustment commands on the fly via the Klipper console.

• Applicable camera module(s): https://a.co/d/a9iFTli (or probably anything similar)

• Prerequisites:

  • Klipper gcode_shell_command extra module here: https://github.com/dw-0/kiauh/blob/master/docs/gcode_shell_command.md

  • or, it might already be installed. Mine was from somewhere.

Installation steps:

1. Create a file that contains a simple script to run when the macro is called. I called mine focus.sh, and I put mine in ~/scripts. From the command line, enter:

nano ~/scripts/focus.sh

2. Add the following contents to the file:

#/bin/sh

v4l2-ctl -d /dev/video9 -c focus_absolute=$1
echo "focus set to $1"

  NOTES:  
  - You may need to change the /dev/video9 to whatever your camera is identified as.  Use the same as what you used in your crowsnest.cfg file.
  - Your focus command might be different too.  Mine was "focus_absolute=_some number 1-1024_".  Check out your crowsnest.log file at ~/printer_data/logs/crowsnest.log.
  - Leave the "$1" alone, we need that to pass the parameter into the script.
  - Make sure you still have the #/bin/sh at the top of the file.

3. Make any changes necessary as described above, and save the file:

   • Hit CTRL+X to exit and then Yes to save.

4. Make the script file executable:

chmod +x ~/scripts/focus.sh

5. Add these lines to your printer.cfg file in Klipper. Or, if you know your way around, you can put them probalby anywhere that has an [include yourfavoritemacros.cfg] in your printer.cfg file.

[gcode_shell_command focus]
command: sh /home/pi/scripts/focus.sh  # The shell command to call the script.  NOTE YOU MIGHT HAVE TO CHANGE pi to BIQU or whatever your username is
timeout: 30.
verbose: False

[gcode_macro SET_FOCUS]
gcode:
    {% set focus_val = params.FOCUS|default("465")|int %}         # set default value 465 to whatever you like
    { action_respond_info("Focus set to: " "%s" % (focus_val)) }  # Echos command in klipper console
    RUN_SHELL_COMMAND CMD=focus PARAMS={focus_val}                # Run the gcode shell command 

[delayed_gcode INITIALIZE_FOCUS]
initial_duration: 5  # Run automatically after initial_duration seconds
gcode:
    SET_FOCUS FOCUS=465 # Set value for focus to suit your fancy

6. Restart Klipper firmware. May as well reboot your host machine as well, for good measure.

USAGE:

This scheme will automatically set the manual focus value (465 in my case), 5 seconds after Klipper starts up.

You can manually set a focus value by sending this from the console (which might be useful for finding what you want to use for your default):

SET_FOCUS FOCUS=<some number you want to try>