Skip to content

Jog, Homing & Terminal

This section covers the FocuZ:grbl controller — the motion-and-accessory controller FocuZ pairs with your galvo controller — and the Jog and Terminal screens that drive it.

The FocuZ:grbl controller

FocuZ uses two controllers that work together:

  • the galvo controller (BJJCZ) steers the laser beam and fires it (see Hardware & Device Setup), and
  • the FocuZ:grbl controller — a custom GRBL build — moves the X / Y / Z axes (stage, gantry, or Z focus) and switches accessory relays.

FocuZ detects the FocuZ:grbl controller automatically when it connects (it identifies itself on the wire), so the homing, jogging, and accessory features described here light up once it's connected.

Two controllers, one job

The galvo marks; the FocuZ:grbl controller handles motion and accessories. A job can interleave both — for example, jog an axis, switch on air assist, mark, then switch it off. How they coordinate within a run is covered in Marking & Tracing.

Jog

Open Jog from the menu. The Jog card gives you homing, axis control, and live position.

TODO screenshot: Jog card

Homing

  • Home X / Home Y / Home Z home each axis independently; Home All runs them in sequence.
  • Each axis tracks its own homing status. An axis must be homed for its absolute position to be trustworthy; homing is what establishes a known origin (by touching the limit switch).
  • After an alarm (e.g. a limit hit) an axis loses its homed status and must be re-homed before its position is trusted again — see Troubleshooting & FAQ.

Axis Enable

Each axis has an Enable checkbox. Enabling an axis includes it in operations that need confident absolute positioning. Whether a run requires a given axis to be homed depends on which axes are enabled and what the job does.

Position & limits

  • MPos is the machine (absolute) position; LPos is the work position FocuZ derives from it.
  • Limit-switch status is shown per axis/direction so you can confirm switches before homing.

Manual jogging

  • Set a jog distance (step size) and jog speed, then use the per-axis jog buttons to move by that step. Arrow-key nudge gives finer control.
  • Home & Jog to Lens 0 homes Z and moves to the active lens's saved focal height in one step — handy for getting straight to focus (see Lenses, Corrections & Calibration).

How jogging really behaves (open-loop)

The FocuZ:grbl controller is open-loop and queues moves:

  • Clicking a jog button several times runs the jogs one after another — each click queues another move.
  • A move is "done" when the controller reports Idle, not when the axis is confirmed to have physically arrived. With no encoder, a stall, a disabled driver, or missed steps are not detected.
  • Positional confidence comes from homing (hitting the limit switch), not from per-move confirmation.

Terminal

Open Terminal to talk to the FocuZ:grbl controller directly. Type a command, press Enter (or Send), and the output window shows what you sent (> …) and the controller's replies. Use it to run G-code, check status, or switch accessory outputs (below).

TODO screenshot: Terminal card

Accessory relays — air, vacuum & more

The FocuZ:grbl controller has several auxiliary relay outputs (switched 24 V / 5 V) you can wire to peripherals — most commonly air assist and a vacuum / extraction fan, but any on/off accessory works.

Each output is switched with an M-code. You can send these:

  • manually, by typing the M-code in the Terminal, or
  • as a job step, with a GRBL - Command action in the Sequencer — e.g. turn air on before a marking action and off after it, so it's automatic every run.

Air assist around a mark (in a job)

  1. GRBL - Command — switch the air-assist output on.
  2. 2D Import (or 3D Slice) — the marking action.
  3. GRBL - Command — switch the output off.

Confirm the codes for your wiring

Which M-code maps to which physical output (and therefore to air vs. vacuum) depends on how your controller is wired and configured. Test each output from the Terminal and label them before relying on them in a job. (Exact output-code table to be documented for the standard FocuZ:grbl build.)

See also