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Other features
LEDs: The eight WS2812 LEDs can be controlled via a single digital line, and don't require any external parts except for a 0.1 µF bypass capacitor.
BNC clock output: We plan on using the BNC connector to send a signal each time the acquisition board takes a sample, but this hasn't been programmed yet. In the meantime, the connector is a great way to ground your board if you're running it off battery power! You would do this by connecting the outer shield of this connector (NOT the center pin) to an appropriate ground – a large metal rack, a piece of copper sunk deep into the wall, or even the ground plug of a 3-prong outlet.
I2C bus: Each of the four HDMI ports includes 2 channels that are connected to an I2C bus. This will provide a convenient way to expand the functionality of the acquisition board through custom I/O boards. However, the I2C functionality hasn't been added to the firmware yet.
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