> For the complete documentation index, see [llms.txt](https://wiki.cbunmanned.com/wiki/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.cbunmanned.com/wiki/products-eol/cbu-cm405-fc-eol/female-header-f405/i2c.md).

# I2C

**I2C**

A single I2C port (Red/Yellow) is available for use with an external Compass. Internally this I2C is shared with the BMP280 Barometer.

<figure><img src="/files/BafvbIuHuqKmv3jiUaRu" alt=""><figcaption></figcaption></figure>