Data Sheet

October 2017 BNO080 Datasheet 1000-3927
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6. The BNO080 supports environmental sensors (e.g. pressure sensors, ambient light sensors) on a secondary
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2
C interface. This interface should be pulled up via resistors regardless of the presence of the external
sensor as the SW polls for sensors at reset.
1.3.3.1 UART operation
The UART is configured for 3Mkb/s, 8 data bits, 1 stop bit and no parity. The UART protocol relies on an idle line
being ‘high’. A transmission is started with the assertion of a start bit (pulling the line low), followed by the data,
LSB first. After the data segment is sent (in this case 8-bits), the line is pulled high (the stop signal) for a minimum
number of bits (1 for the BNO080) to indicate end of that segment. Bytes sent from the host to the BNO080 must
be separated by at least 100us. Bytes sent from the BNO to the host have no extra spacing.
Figure 1-19: UART signaling
The BNO080 uses Hillcrest’s SHTP protocol to communicate. The UART protocol makes use of framing bytes at
the start and end of transmission. More details are available in [2].
1.3.4 SPI Interface
The BNO080 supports 4-wire Serial Peripheral Interface (SPI) for host communication. A typical connection
diagram is provided in Figure 1-20.
Start
Stop
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