DEVELOPBY UNEXPECTED MAKER

Develop

Languages, development tools and ready-made projects for your next build.

If this is your first time using an Unexpected Maker development board, please check out the Getting Started guide → first.

Languages / platforms

Choose your language and development tools. Runtime support varies by chip; follow the linked project’s hardware requirements and board setup.

CircuitPython

Write Python for sensors, displays and your next hardware idea.

Choose your MCU

1

Download CircuitPython for your board

Your board ships with CircuitPython and the UF2 bootloader installed. Follow these steps to update CircuitPython, or to reinstall it after using Arduino, MicroPython or ESP-IDF.

Open your board’s page on circuitpython.org and download the latest CircuitPython version as a .uf2 file.

CircuitPython downloads and bootloader drive names
Your boardCircuitPython downloadBootloader drive
TinyS2TinyS2TINYS2BOOT
FeatherS2FeatherS2UFTHRS2BOOT
FeatherS2 NeoFeatherS2 NeoFS2NEOBOOT
  • .uf2 installs by copying it onto the bootloader drive. Use it to install or update CircuitPython.
  • .bin is a complete firmware image, written over USB with the web installer or esptool while the board is in download mode. It doesn’t need the UF2 bootloader; use it if the bootloader isn’t installed.

Whichever file you use, once CircuitPython is running your board appears as a USB drive named CIRCUITPY, which holds your code.

2

Put your board into UF2 bootloader mode

The UF2 bootloader (TinyUF2) is a small program, separate from CircuitPython. In bootloader mode your board appears as a USB drive named for the board, such as TINYS2BOOT; the table in step 1 lists the name for each board. This bootloader drive is only for installing CircuitPython; it is not where your code lives.

1Tap RESET

Press and release RESET.

2Tap BOOT on purple

When the RGB LED turns purple, press and release BOOT.

3LED turns green

Your board’s bootloader drive appears on your computer.

Every new UM board that ships with CircuitPython has the UF2 bootloader installed. If the LED turns purple but no drive appears, BOOT was pressed too late: run the sequence again and press BOOT while the LED is still purple.

LED doesn’t turn purple? Install the UF2 bootloader.

3

Copy the .uf2 file to the bootloader drive

Drag the .uf2 file onto your board’s bootloader drive, not onto CIRCUITPY. The board installs it and restarts by itself. Your computer may warn that the drive was removed; this is normal.

When the CIRCUITPY drive appears, CircuitPython is running.

Deployable projects

Ready-made firmware and connected applications for lighting, sensors and home automation. Follow each project’s supported hardware and configuration guide.