ScottW514
4eb0932099
Under the FIRE-bit dose model the duty is pinned at full and the level is carried by how many ticks of each base period fire, so a rung's pulse is density x period - and the base period is the one parameter the host cannot settle. dladder walks 5 to 100 percent of dose on scrap at constant power, printing what each rung actually emits: density, mean on-ticks, and the pulse the tube sees in ticks and microseconds. Below one tick per period the pulse stays one tick and whole periods are skipped instead, which the table says outright rather than quoting a sub-tick average. Run it at 20, then 40, then 10 on the same material. At 20 percent dose that is 107-142 us, 249-284 us and 36-71 us respectively, which brackets the 100 us the factory never goes below. The material answers two questions: whether depth tracks density linearly, or the low end marks harder than its share because every burst restarts the discharge and carries the strike transient; and how short a burst still marks, which is the floor a given base period can reach. Preconditions are refusals, not warnings: laser_power_model must already be density and $35 must be 0, since a floor lifts every rung off the bottom of the range the drill exists to explore. The $35 message says a runtime write is not enough - the S to duty mapping is precomputed when the spindle is enabled. The drill writes laser_pulse_ticks itself when it can reach the machine config, preserving every other line, and refuses with instructions when run from a LAN host where it cannot.
OpenGlow/ForgeFIRM Firmware for Glowforge
Open-source firmware for Glowforge brand CNC lasers. ForgeFIRM replaces the cloud-dependent factory software on the stock control board — no hardware modification — and gives the machine a local controller, a local web control panel, and a standard Grbl interface.
- Latest Release
- Installation Instructions
- Build Instructions
- Connecting LightBurn
- How motion and the laser are driven
- How cooling and airflow work
- The cameras and the video stream
- How the laser safing works
- How a release is accepted
- Community Support
What it does
Two controller modes, selected in the web panel and switchable while the machine is idle:
- GRBL mode — grblHAL runs on the machine and speaks Grbl 1.1 over TCP port 23, so LightBurn, UGS, and cncjs drive the laser directly. Motion runs on the board's own hardware step engine (SDMA + EPIT), fed live by the planner. M3/M4 dynamic laser power, coolant-flow verification, over-temp holds, and an operator button press to arm the laser for each job.
- Cloud mode — the machine presents itself as a stock Glowforge to the Glowforge web service, so the phone and web apps work as they always did. Optional, and off by default. GRBL mode jogs and cuts without it; the one GRBL-mode function that still reaches the Glowforge service is camera-referenced homing (below), until limit-switch homing lands.
Around both modes:
- A web control panel on port 8080: machine status and position, coolant and fan telemetry, safety-switch states, camera view, machine settings, hardware diagnostics, firmware updates, and boot-slot management.
- Camera-referenced homing:
$Hfrom any sender runs the factory-style camera homing cycle through the Glowforge service (a Glowforge account and a live service session are required for$H; everything else in GRBL mode runs without them), and the machine records where it is. - Cameras only capture with the lid closed. The lid camera faces the room once the lid is raised, so ForgeFIRM refuses every capture — live view, snapshot, and anything the Glowforge service asks for in cloud mode — until the enclosure is shut, and stops a running stream the moment the lid opens. See the cameras and the video stream.
Hardware
The control board is common to Glowforge Basic, Plus, and Pro. The 5 MP (OV5648) camera modules are fully supported and hardware-validated. The 8 MP (OV8856) modules found in "HD" units have a complete capture path — the kernel patches, device tree and sensor-aware capture profile they need are all in the build — but it has never run on an 8 MP machine, so treat it as untested; see the camera note in kas/README.md.
Safety
These machines contain a CO₂ laser: it burns, blinds, and starts fires. Never defeat the lid switches or interlock. Never leave a running job unattended — keep a fire extinguisher within reach. Read Before you cut — safety before your first job, and the Regulatory and legal section before installing. How the laser safing works describes the hardware safety chain and the software gates ForgeFIRM stacks on it.
A very important warning: this is experimental software. Use of this software could seriously maim or kill you or others, and voids your warranty. It is not affiliated with or endorsed by Glowforge. Use it at your own risk.