Kauai Labs navX-MXP User Manual page 29

Installation
Alternative Installation Options
Connector
If any of the "one-wire" methods described above is not desirable, you may also interface to the
navX-MXP circuit board using the Power, Ground and I2C/SPI/TTL UART signals on the MXP
Connector.
I2C
To use the I2C interface without directly plugging the navX-MXP circuit board into the RoboRIO
MXP connector, first ensure that the navX-MXP circuit board has power (either via the USB
connector, or via the +5VDC pin on the MXP connector).
Next, make sure that the digital ground from the host computer (e.g., the RoboRIO) is
connected to one of the GND pins on the MXP connector.
Finally, connect the SDA and SCL pins on the host computer (e.g., the RoboRIO) to the
corresponding SDA and SCL pins on the navX-MXP circuit board.
Note that the I2C bus expects that the SDA and SCL pins be pulled up with a pull-up resistor on
each line. The RoboRIO internally pulls these lines high.
The I2C pins are 5V tolerant, so the host computer can use either 5V or 3.3V DC levels on
these pins.
SPI
To use the SPI interface without directly plugging the navX-MXP circuit board into the RoboRIO
MXP connector, first ensure that the navX-MXP circuit board has power (either via the USB
connector, or via the +5VDC pin on the MXP connector).
Next, make sure that the digital ground from the host computer (e.g., the RoboRIO) is
connected to one of the GND pins on the MXP connector.
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