Details for switching on/off the MOSFETs via either Web-UI buttons or in GCode:

[DougJoseph (Doug Joseph (design8studio))]

Location on the board (upper right corner):

Web-UI buttons

In the FluidNC web-based GUI, the buttons labeled “Flood” and “Mist” turn the MOSFETs on/off:

GCode

According to the FluidNC WIki — Supported Gcodes | Wiki.js …

M7 / M7.1 - Mist Coolant

• M7 ; Turns on 2nd MOSFET on right side, VMOT-> GPIO.16
• M7.1 ; Turns off 2nd MOSFET on right side, VMOT-> GPIO.16

M8. / M8.1 - Flood Coolant

• M8 ; turns on 1st MOSFET on left side, VMOT-> GPIO.2
• M8.1 ; turns off 1st MOSFET on left side, VMOT-> GPIO.2

[Mattman (Matt K)]

@DougJoseph

M8 ; turns on 1st MOSFET on left side, VMOT-> GPIO.2

Doug, could one use ‘M8’ in the ‘startup_line0’ config line so when the ESP/Jackpot reboots once fluidnc goes into the idle state, that MOSFET would turn on? I tried, AND DID have success. Typing in M8/M8.1 does turn the fan on/off when connected to that MOSFET.

[DougJoseph (Doug Joseph (design8studio))]

@Mattman

Doug, could one use ‘M8’ in the ‘startup_line0’ config line

That certainly seems like a workable approach!