Spindle, Vacuum, and Laser control SKR PRO

This might be close to another topic.
I am using the software for dual end stop, and noted the menu had spindle and laser controls.
I have a dual relay wired and control the spindle from the relay.
I also ran a wire for my laser, and can remove the router and put a laser in its stead, then use the laser control.
I want to add a menu button for the vacuum, and also turn it on from, the menu, any idea how to do that?
I have 4 conductors going to the relay box, +5, Ground, and two relay signal leads. The relay has optical isolated inputs.
Config.h (already) had #define SPINDLE_LASER_ENABLE_PIN PC9, and I use that for the spindle relay.
(minor change to invert the signal but it works)

Not sure how to proceed, maybe using PF9, but how to add a menu for the vacuum

I’m using grbl rather than Marlin on my MPCNC and K40 laser. My board and firmware provides 2 coolant pins/modes, flood and mist. I use those for on/off accessories like the exhaust fan and air assist on the laser and am planning to do the same for a chip blower and vacuum hold-down on the MPCNC. A look at these docs seems to indicate Marlin supports these options too, through directives in configuration_adv.h but I can’t tell which pins you’ll need to connect the relays to.

I assume you are triggering these commands from the TFT display. To add menu items, you will need to edit the firmware for the TFT display. Go to this page and you will find a link to the source for the firmware in the TFT Files section of the webpage.

Note that my solution was to use the same relay for the vacuum as the spindle. Then I added a switch for the vacuum that is On/OFF/Spindle so that I can override the spindle and either have the vacuum off, or turn it on without the spindle for cleanup.

Thanks, I have those files, but making the changes to add a menu item is a bit much for a noob