Choose your trigger mode - Mechanical vs Digital

The FarmBoard runs your machine through a four-step cycle on every print:

1. Close door
2. Open door + fan
3. Bending
4. Close door, return to idle

You can drive this cycle two ways, and both run automatically during a print - neither needs a person standing at the machine. In Mechanical mode the printer’s bed presses the limit switch via the print’s G-code moves; in Digital mode the printer tells the FarmBoard over Wi-Fi. Digital mode is recommended for production. Mechanical mode is the always-available fallback and works without any network.

The two modes at a glance

	Mechanical	Digital (Full MQTT)
Wi-Fi required	No	Yes
LAN-only mode required	No	Yes
Reliability	High	Very high

You can switch between modes any time from the OTA page - both stay configured.

Mechanical mode

Each cycle step is triggered by pressing the limit switch on the machine - the printer’s bed presses the switch automatically as part of the print’s G-code moves, so no operator is needed. The different press patterns (long presses and taps in the table below) are produced by the programmed bed movements. Works on every kit regardless of network connection, and is always available as a fallback even when Digital is enabled.

Step	Bed press pattern	What happens
1. Close door	Long press (3-6 s) + short tap	Door closes, print can begin
2. Open door + fan	Long press (4-8 s) at end of print	Door opens, fan starts cooling
3. Start bending	Triple tap within 8 s	Fan off, bending cycle runs
4. Close door + finish	Long press (4-8 s)	Door closes, returns to idle

A few helpers on top of the four steps:

• Safety check (current sense): double-tap during the safety window
• Skip safety check: long press during the safety window
• Emergency reset: four quick taps within 10 s - homes the bender and returns to idle

Digital mode (Full MQTT)

The FarmBoard talks directly to your Bambu Lab printer over Wi-Fi. The printer publishes its state in real time and the FarmBoard fires each step at the exact right moment - door close at print start, door open + fan at the last layer, bender after cooldown, door close on finish. No button presses.

What you need

• The printer and the FarmBoard on the same Wi-Fi network.
• The printer set to LAN-only mode (Bambu Studio settings → Network → LAN Mode → on). Digital mode talks to the printer over the local MQTT broker, which is only exposed in LAN-only mode.
• Developer mode enabled on the printer (printer Settings → General → Developer Mode → on). Required for Bambu’s LAN MQTT access.
• Your print file processed by the FarmLoop app, version 2.7 or higher. The app renames the processed file with an FL_S2_ prefix and injects the silent timing markers the FarmBoard listens for.
• Digital mode enabled on the FarmBoard’s OTA page, with your printer’s IP address and LAN access code entered.

Don’t rename the FL_S2_* file

Send the file the FarmLoop app produced as-is. Renaming or re-saving it (in Bambu Studio, your file browser, etc.) can strip the markers the FarmBoard relies on, and the cycle won’t fire. Re-process through the app if you need a new file.

Setup

1. Enter OTA mode on the FarmBoard. The per-board gesture and web-UI access (http://farmloop.local) live on the Accessing the board (OTA mode).
2. On the OTA page, fill in the Printer Connection card:
   • Wi-Fi SSID + password (your home / shop network)
   • Printer IP - printer Settings → Wi-Fi
   • LAN access code - printer Settings → Network → LAN Mode (8 digits)
   • Serial number - printer Settings → Device
3. Tick Enable MQTT auto-trigger, click Save Printer Config, then Exit OTA Mode.

After reboot, the LED tells you what happened:

• 5 slow blinks + 10 fast blinks → Wi-Fi and MQTT both connected. You’re set.
• 2 long blinks → Wi-Fi failed; recheck SSID + password.
• 4 long blinks → MQTT failed; recheck the printer IP and LAN access code, and confirm LAN Mode is enabled on the printer.

Things to know

• The limit switch is disabled while Digital mode is connected, so an accidental press during a running print doesn’t interfere. To use the limit switch for testing or maintenance, turn Digital mode off on the OTA page or take the printer off the network.
• Local-only. MQTT runs on your LAN. Nothing leaves your network.
• Wi-Fi drop fallback. If the connection drops mid-print, the FarmBoard falls back to manual mode automatically. When the network returns, MQTT reconnects.
• Cancelled prints. Cancel from Bambu Studio or the printer screen and the FarmBoard opens the door and homes the bender automatically - no manual reset needed.
• “Stopped” in Bambu Studio. Bambu Studio sometimes labels a successful FarmLoop print as Stopped instead of Finished. That’s a display quirk in how it reads the gcode end. The FarmBoard completes its sequence correctly regardless.

Which should you use?

• Testing the kit, doing one-off prints, or your printer isn’t on Wi-Fi → Mechanical.
• Production, unattended runs → Digital. Set it up once; every FL_S2_* file after that runs the full cycle automatically.

Next step

With your trigger mode chosen, move on to Step 5, verify your installation.