Woodpecker CNC GPIO

The external contacts are all GND. Internal connectors as follow:

• X-Axis Limit
• X-Axis Limit
• Y-Axis Limit
• Y-Axis Limit
• Z-Axis Limit
• Z-Axis Limit
• A5 = Probe
• A4 =
• A3 = Coolant Enable
• A2 = Cycle Start/Resume
• A1 = Feed Hold
• A0 = Reset/Aboat
• A7 =
• A6 =
• D13 = Spindel Direction
• RST
• 5V

(more at https://github.com/gnea/grbl/issues/123)