Quickstart: Loader (USB)

A loader device carries a tiny, untouchable helper called rfx_boot alongside the RFX Effects firmware. It turns firmware updates into a drag-and-drop: the device shows up as a USB drive, you drop a file on it, done. No WiFi needed, no apps to install, and a built-in recovery mode you can’t lock yourself out of.

This is the right page if your device came set up in loader mode. If your device updates over WiFi instead, see the Standalone quickstart. If you have a blank board, start at First-time flashing.

The two drives, at a glance

A loader device can show up on your computer as one of two different USB drives, depending on what mode it’s in:

Drive	When you see it	What it’s for
rfx-boot	Update/recovery mode	Drop firmware (firmware.uf2) here
The data drive	While the show is running (boards with on-chip storage)	Your show.json, fonts, sounds, config.json

If you remember one thing from this page: firmware goes on rfx-boot, everything else goes on the data drive.

1. Plug in and power up

Connect the device to your computer with a USB cable. The show starts playing, and on boards with on-chip storage the data drive appears in your file manager — a plain USB drive holding show.json and the rest of the device’s files.

Note

On SD-card boards, the data lives on the removable microSD card instead — pop it into your computer to edit files. Check your board’s page under Boards to see which kind you have.

2. Load or change your show

Edit show.json (or drop in a new one, plus any fonts or sounds) on the data drive or SD card. The device re-reads it on reload or reboot — no rebuilding, no firmware update needed. Behavior is 100% data.

If the device is on WiFi, the web dashboard works exactly as in standalone mode — you can edit the show, upload files, and watch it live from a browser. See the Standalone quickstart for the dashboard tour and WiFi & network setup to get it connected.

3. Update the firmware (drag and drop)

1. Get the new firmware.uf2 for your device.
2. Put the device in update mode: tap RESET, then press BOOT (within about half a second). The rfx-boot drive appears in your file manager.
3. Drag firmware.uf2 onto the rfx-boot drive. The file streams straight into the firmware slot; when it finishes, the device reboots into the new firmware automatically.

That’s the whole update. Your show, config, and other data are untouched — firmware and data live in separate places.

Caution

The gesture is tap RESET first, then press BOOT — two separate presses. Holding BOOT while you press RESET does something different (it puts the chip in low-level download mode, used for first-time flashing — the screen stays dark and no drive appears). If that happens, just tap RESET alone and try again.

Button locations vary by board — see your board’s page under Boards.

4. Check what’s installed

While the rfx-boot drive is showing, open rfx-info.log on it — the loader writes the installed app’s firmware version there. The version also appears in the web dashboard header when the show is running.

Recovery: you can’t get locked out

If a bad show or a bad firmware image crashes the device before it finishes starting, the loader notices: after 3 failed boots in a row it stops trying and brings up the rfx-boot drive by itself. From there:

1. Drop a known-good firmware.uf2 — for example the version that worked before.
2. The device reboots into it; fix whatever was wrong (often a show.json edit) and carry on.

A brand-new or freshly-erased device behaves the same way: with no valid firmware installed, the loader just sits in drive mode waiting for a .uf2. The loader itself never updates at runtime, so no app update can ever damage your recovery path.

Next steps

• Your first show — write a show.json from scratch
• WiFi & network setup — put the device on your network for the dashboard
• Boards — where RESET and BOOT are on your board, and how its storage works
• Troubleshooting — when something doesn’t behave