FluidNC does not directly support e-stop buttons. This is intentional. An e-stop button should cut the primary power. Relying on firmware defeats one of the primary purposes of having an e-stop.
If you want to stop quickly, but it is not a true emergency and the firmware is still running, you can use these control inout alternatives. All of these can be sent via a gcode sender, the WebUI or a hardware button.
- Feed Hold. This very quickly stops the machine without loss of position. It can be resumed with cycle start. The feed hold command is the "!" character. The hardware pin is setup with feed_hold_pin.
- Reset. This immediately stops the machine and spindle, but position is lost and you will need to re-home. Motors will stay engaged if your idle_ms value is 255. The command is CTRL-X (0x18). The hardware pin is setup with reset_pin. This could be used in parallel with a true e-stop. The power will be cut and FluidNC will reset.
- Door/Parking. This feature is used for an enclosure door. If the door is opened during a job, the motion will quickly stop, the bit will retract, the spindle will stop and retract further from the work. The command is character 0x84. The hardware pin is setup with safety_door_pin.
control:
safety_door_pin: NO_PIN
reset_pin: NO_PIN
feed_hold_pin: NO_PIN