MIKROE SmartDOF Click

SmartDOF Click features a highly advanced integrated system-in-package (SiP) solution with three different sensors on-chip: triaxial accelerometer, magnetometer, and triaxial gyroscope are all integrated on the same die, along with the powerful 32-bit ARM® Cortex®-M0+ MCU. Thanks to the integrated MCU, the BN080 SiP provides extensive signal processing. This allows many features to be implemented, including the MotionEngine™ support. The MotionEngine™ software allows extensive data modes and events detection. The BNO080 also supports the dynamic calibration of the sensors for temperature and aging, offering ultimate accuracy and reliability.

SmartDOF Click is supported by a mikroSDK compliant library, which includes functions that simplify software development. This Click board™ comes as a fully tested product, ready to be used on a system equipped with the mikroBUS™ socket.

Built to be used as a simple solution, this 9 DOF SiP provides an output which can be used directly, with no tedious conversions required. Acting as a co-processor, it reduces the workload from the host MCU, allowing it to be used for other tasks, such as handling of the interrupt requests. Despite its complexity, BN080 SiP still reduces the overall power consumption, allowing various “always-on” features which can be used to wake up the host MCU and the rest of the system. Thanks to its many features, SmartDOF Click can be used for the development of various motion-based applications, including VR/AR applications, robotics, VR/AR headsets, wearable motion controllers, and similar.

The Click board™ is based on the BNO080, a System in Package (SiP) that integrates a triaxial accelerometer, triaxial gyroscope, magnetometer and a 32-bit ARM® Cortex®-M0+ MCU, produced by Hillcrest Labs. The integrated MCU core runs the proprietary Hillcrest SH-2 firmware, which includes the support for the MotionEngine™ software and its sophisticated signal processing algorithms. Thanks to this, the SmartDOF can provide very accurate and precise 3D acceleration, magnetic, and angular velocity data, in real-time. The additional output modes include orientation outputs by combining data from various sensors. There are many different rotation vectors available on a top of other readings, including geomagnetic rotation vector (does not use the gyroscope sensor), game rotation vector (no magnetometer), etc. The datasheet of the BNO080 offers a full list of outputs, each with a detailed explanation.

As a device built to be used primarily in smartphones, BNO080 brings events detection and classification system. Stability classification distinguishes among three stability classes: “on the table” (the device is at a fixed position), “stable” (held in hand but in a stationary manner), or at “motion” (the device is in motion). Stability classification is not the only classification for this device. For more information, please refer to the datasheet of the BN080 SiP.

The detection engine allows many different events to be detected and reported as an interrupt, including tap detector, step detector, step counter, shake detector, etc. Both classification and detection systems use configurable thresholds. More information about how to set them up can be found in the SH-2 Reference Manual. However, the mikroSDK compatible library offers a well-documented set of functions, for simplified firmware development.

The BNO080 offers both static and dynamic calibration features, which allow for increased precision. Static calibration is applied to the output data for the properties which do not change over time, or with temperature (i.e cross-axis sensitivity, gain, sensor orientation in respect to the frame of reference…) Dynamic calibration is used for the parameters which vary over time or temperature (i.e. zero-rate offset, zero-g offset…)

Besides the compensation parameters, the user is able to tare the device, using two tare modes: tare around all axes, or tare around the z-axis. The result of a tare operation is applied wherever power is applied to the device. The tare value can be permanently stored with the Persist Tare function.

The BNO080 will be started in the Bootloader mode. This mode allows updating the embedded firmware over the I2C interface. When this pin is pulled to a LOW logic level, the device will boot up in the Bootloader mode after the next restart. This pin is routed to the mikroBUS™ PWM pin and it is labeled as BT. The BNO080 datasheet describes the firmware update process in more details.

The Click board™ uses the I2C interface to communicate with the host MCU. It has an SMD jumper labeled as ADD SEL, which can be used to select the peripheral I2C address. This allows more than one device on a single I2C bus.

The Click board™ is designed to work with 3.3V only. When using it with MCUs that use 5V levels for their communication, a proper level translation circuit should be used.

• Interface: I²C
• Compatibility: mikroBUS™
• Dimensions: 42.9 x 25.4mm
• Input Voltage: 3.3V