> For the complete documentation index, see [llms.txt](https://dahl-design.gitbook.io/ddc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dahl-design.gitbook.io/ddc/fast-ddc/4-encoders-buttons-and-led.md).

# 4 encoders, buttons and LED

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* Hold button 1 and 2 together for 5 seconds to restart the controller and boot as storage device.
* LEDs are running on 3.3V data in this diagram, which works up to a certain LED count. Limit is set to 30 because more is unlikely to work. For higher LED counts use a level shifter and set up a full DDC firmware.&#x20;