6 Introduction to Using grblHAL

V5.77 grblHAL support and the important differences from FluidNC

Do not flash the FluidNC YAML into grblHAL. The YAML and all commands in sections 2-4 of this tutorial were prepared for FluidNC 4.0.x.

Why This Chapter Is Separate

FluidNC assigns GPIOs and features in a YAML file, so one broad test configuration can exercise most of the V5.77 hardware. grblHAL builds and board maps are comparatively fixed: enabled plugins, pin assignments, and available functions depend on the exact firmware build.

Current V5.77 Guidance

Use only a grblHAL ESP32-S3 build and board map that explicitly names the PiBot V5.77 Carrier revision.
Confirm the ESP32-S3 module's GPIO.38 / GPIO.48 RGB-LED revision before selecting a pin map.
Do not assume FluidNC tool numbers, UART channels, coolant assignments, or user-output commands are identical.
Back up the working FluidNC installation and files before changing firmware.

Support status: PiBot V5.77 Carrier supports grblHAL. Use a compatible ESP32-S3 firmware build and a board map that matches the V5.77 hardware and plug-in module revision. The FluidNC test YAML and FluidNC commands in sections 2–4 are not a grblHAL configuration and must not be copied across unchanged.

Continue to 7 Software Introduction.