a collection of miscellaneous projects of Paul Philippov

Woodpecker CNC Useful Tips

GPIO pinout

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

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How to connect ICSP

Woodpecker 2.7 GRBL board ICSP connections are available via through holes beneath the main I/O header.

  • Vcc
  • (gap)
  • GND
  • RST
  • SCK
  • MOSI
  • MISO

How to connect TTL laser

Pin11 (Spindle_enable) is a PWM pin. You wire the TL(TTL_Low) to ground of Arduino and TH(TTL_High) to Pin11 (Spindle_enable) and you can dim it by feeding it an S command from zero to what ever you have $30 at. Be careful - on old board shields(v3.0 and older), the z_Limit and Spindle_enable pins are swapped. Because the z_Limit is held high by the arduino, it may fire the laser and keep it on.