The library needs to be tested once we get the IMU
Diff: BNO080.h
- Revision:
- 0:f677e13975d0
- Child:
- 1:aac28ffd63ed
diff -r 000000000000 -r f677e13975d0 BNO080.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/BNO080.h Sun Dec 23 05:23:21 2018 +0000 @@ -0,0 +1,453 @@ +/* + * This is USC RPL's ARM MBed BNO080 IMU driver, by Jamie Smith. + * + * It is based on SparkFun and Nathan Seidle's Arduino driver for this chip, but is substantially rewritten and adapted. + * It also supports some extra features, such as setting the mounting orientation and + * enabling some additional data reports. + * + * This driver uses no dynamic allocation, but does allocate a couple hundred bytes of class variables as buffers. + * This should allow you to monitor its memory usage using MBed's size printout. + * + * The BNO080 is a very complex chip; it's capable of monitoring and controlling other sensors and making + * intelligent decisions and calculations using its data. Accordingly, the protocol for communicating with it + * is quite complex, and it took me quite a while to wrap my head around it. If you need to modify or debug + * this driver, look at the CPP file for an overview of the chip's communication protocol. + * + * Note: this driver only supports I2C. I attempted to create an SPI version, but as far as I can tell, + * the BNO's SPI interface has a bug that causes you to be unable to wake the chip from sleep in some conditions. + * Until this is fixed, SPI on it is virtually unusable. + */ + +#ifndef HAMSTER_BNO080_H +#define HAMSTER_BNO080_H + +#include <mbed.h> +#include <quaternion.h> + +#include "BNO080Constants.h" + +class BNO080 +{ + /** + * Serial stream to print debug info to. Used for errors, and debugging output if debugging is enabled. + */ + Serial * _debugPort; + + /** + * I2C port object + */ + I2C _i2cPort; + + /// user defined port speed + int _i2cPortSpeed; + + /// i2c address of IMU (7 bits) + uint8_t _i2cAddress; + + DigitalIn _int; + DigitalOut _rst; + + DigitalOut _scope; + + // packet storage + //----------------------------------------------------------------------------------------------------------------- + +#define SHTP_HEADER_SIZE 4 +#define STORED_PACKET_SIZE 128 + + /// Each packet has a header of 4 uint8_ts + uint8_t shtpHeader[SHTP_HEADER_SIZE]; + + /// Stores data contained in each packet. Packets can contain an arbitrary amount of data, but we shouldn't need to read more than a few hundred bytes of them. + /// The only long packets we actually care about are batched sensor data packets, and with how this driver handles batching, we *should* only have to deal + /// with at most 9 reports at a time = ~90 bytes + a few bytes of padding + uint8_t shtpData[STORED_PACKET_SIZE]; + + /// Length of packet that was received into buffer. Does NOT include header bytes. + uint16_t packetLength; + + /// There are 6 com channels. Each channel has its own seqnum + uint8_t sequenceNumber[6] = {0, 0, 0, 0, 0, 0}; + + /// Commands have a seqNum as well. These are inside command packet, the header uses its own seqNum per channel + uint8_t commandSequenceNumber = 0; + + // data storage + //----------------------------------------------------------------------------------------------------------------- + + // 1 larger than the largest sensor report ID +#define STATUS_ARRAY_LEN 0x1A + + /// stores status of each sensor, indexed by report ID + uint8_t reportStatus[STATUS_ARRAY_LEN] = {}; + +public: + + /// List of all sensor reports that the IMU supports. + enum class Report : uint8_t + { + /** + * Total acceleration of the IMU in world space. + * See BNO datasheet section 2.1.1 + */ + TOTAL_ACCELERATION = SENSOR_REPORTID_ACCELEROMETER, + + /** + * Acceleration of the IMU not including the acceleration of gravity. + * See BNO datasheet section 2.1.1 + */ + LINEAR_ACCELERATION = SENSOR_REPORTID_LINEAR_ACCELERATION, + + /** + * Acceleration of gravity felt by the IMU. + * See BNO datasheet section 2.1.1 + */ + GRAVITY_ACCELERATION = SENSOR_REPORTID_GRAVITY, + + /** + * (calibrated) gyroscope reading of the rotational speed of the IMU. + * See BNO datasheet section 2.1.2 + */ + GYROSCOPE = SENSOR_REPORTID_GYROSCOPE_CALIBRATED, + + /** + * (calibrated) reading of magnetic field levels. + * See BNO datasheet section 2.1.3 + */ + MAG_FIELD = SENSOR_REPORTID_MAGNETIC_FIELD_CALIBRATED, + + /** + * Fused reading of the IMU's rotation in space using all three sensors. This is the most accurate reading + * of absolute orientation that the IMU can provide. + * See BNO datasheet section 2.2.4 + */ + ROTATION = SENSOR_REPORTID_ROTATION_VECTOR, + + /** + * Fused reading of rotation from accelerometer and magnetometer readings. This report is designed to decrease + * power consumption (by turning off the gyroscope) in exchange for reduced responsiveness. + */ + GEOMAGNETIC_ROTATION = SENSOR_REPORTID_GEOMAGNETIC_ROTATION_VECTOR, + + /** + * Fused reading of the IMU's rotation in space. Unlike the regular rotation vector, the Game Rotation Vector + * is not referenced against the magnetic field and the "zero yaw" point is arbitrary. + * See BNO datasheet section 2.2.2 + */ + GAME_ROTATION = SENSOR_REPORTID_GAME_ROTATION_VECTOR, + + /** + * Detects a user tapping on the device containing the IMU. + * See BNO datasheet section 2.4.2 + */ + TAP_DETECTOR = SENSOR_REPORTID_TAP_DETECTOR, + + /** + * Detects whether the device is on a table, being held stably, or being moved. + * See BNO datasheet section 2.4.1 + */ + STABILITY_CLASSIFIER = SENSOR_REPORTID_STABILITY_CLASSIFIER, + + /** + * Detects a user taking a step with the IMU worn on their person. + * See BNO datasheet section 2.4.3 + */ + STEP_DETECTOR = SENSOR_REPORTID_STEP_DETECTOR, + + /** + * Detects how many steps a user has taken. + * See BNO datasheet section 2.4.4 + */ + STEP_COUNTER = SENSOR_REPORTID_STEP_COUNTER, + + /** + * Detects when the IMU has made a "significant" motion, defined as moving a few steps and/or accelerating significantly. + * See BNO datasheet section 2.4.6 + */ + SIGNIFICANT_MOTION = SENSOR_REPORTID_SIGNIFICANT_MOTION, + + /** + * Detects when the IMU is being shaken. + * See BNO datasheet section 2.4.7 + */ + SHAKE_DETECTOR = SENSOR_REPORTID_SHAKE_DETECTOR + }; + + // data variables to read reports from + //----------------------------------------------------------------------------------------------------------------- + + // @{ + /// Version info read from the IMU when it starts up + uint8_t majorSoftwareVersion; + uint8_t minorSoftwareVersion; + uint16_t patchSoftwareVersion; + uint32_t partNumber; + uint32_t buildNumber; + // @} + + + /** + * Readout from Accleration report. + * Represents total acceleration in m/s^2 felt by the BNO's accelerometer. + */ + TVector3 totalAcceleration; + + /** + * Readout from Linear Acceleration report. + * Represents acceleration felt in m/s^2 by the BNO's accelerometer not including the force of gravity. + */ + TVector3 linearAcceleration; + + /** + * Readout from Gravity report. + * Represents the force of gravity in m/s^2 felt by the BNO's accelerometer. + */ + TVector3 gravityAcceleration; + + /** + * Readout from Calibrated Gyroscope report + * Represents the angular velocities of the chip in rad/s in the X, Y, and Z axes + */ + TVector3 gyroRotation; + + /** + * Readout from the Magnetic Field Calibrated report. + * Represents the magnetic field read by the chip in uT in the X, Y, and Z axes + */ + TVector3 magField; + + /** + * Readout from the Rotation Vector report. + * Represents the rotation of the IMU (relative to magnetic north) in radians. + */ + Quaternion rotationVector; + + /** + * Auxillary accuracy readout from the Rotation Vector report. + * Represents the estimated accuracy of the rotation vector in radians. + */ + float rotationAccuracy; + + /** + * Readout from the Game Rotation Vector report. + * Represents the rotation of the IMU in radians. Unlike the regular rotation vector, the Game Rotation Vector + * is not referenced against the magnetic field and the "zero yaw" point is arbitrary. + */ + Quaternion gameRotationVector; + + /** + * Readout from the Geomagnetic Rotation Vector report. + * Represents the geomagnetic rotation of the IMU (relative to magnetic north) in radians. + */ + Quaternion geomagneticRotationVector; + + /** + * Auxillary accuracy readout from the Geomagnetic Rotation Vector report. + * Represents the estimated accuracy of the rotation vector in radians. + */ + float geomagneticRotationAccuracy; + + /** + * Tap readout from the Tap Detector report. This flag is set to true whenever a tap is detected, and you should + * manually clear it when you have processed the tap. + */ + bool tapDetected; + + /** + * Whether the last tap detected was a single or double tap. + */ + bool doubleTap; + + + // Management functions + //----------------------------------------------------------------------------------------------------------------- + + /** + * Construct a BNO080, providing pins and parameters. + * + * NOTE: while some schematics tell you to connect the BOOTN and WAKEN pins to the processor, this driver does not use or require them. + * Just tie them both to VCC per the datasheet. + * + * @param debugPort Serial port to write output to. Cannot be nullptr. + * @param user_SDApin Hardware SPI MOSI pin + * @param user_SCLpin Hardware SPI MISO pin + * @param user_SCLKPin Hardware SPI SCLK pin + * @param user_CSPin SPI CS pin. Can be any IO pin, no restrictions. + * @param user_INTPin Input pin connected to HINTN + * @param user_RSTPin Output pin connected to NRST + * @param i2cPortSpeed SPI frequency. The BNO's max is 3Mhz, we default to 300Khz for safety. + */ + BNO080(Serial *debugPort, PinName user_SDApin, PinName user_SCLpin, PinName user_INTPin, PinName user_RSTPin, + uint8_t i2cAddress=0x4a, int i2cPortSpeed=400000); + + /** + * Resets and connects to the IMU. + * + * If this function is failing, it would be a good idea to turn on BNO_DEBUG in the cpp file to get detailed output + * + * @return whether or not initialization was successful + */ + bool begin(); + + /** + * Tells the IMU to use its current rotation vector as the "zero" rotation vector and to reorient + * all outputs accordingly. + * + * @param zOnly If true, only the rotation about the Z axis (the heading) will be tared. + */ + void tare(bool zOnly = false); + + /** + * Tells the IMU to begin a dynamic sensor calibration. To calibrate the IMU, call this function and move + * the IMU according to the instructions in the "BNO080 Sensor Calibration Procedure" app note + * (http://www.hillcrestlabs.com/download/59de9014566d0727bd002ae7). + * + * To tell when the calibration is complete, look at the status bits for Game Rotation Vector (for accel and gyro) + * and Magnetic Field (for the magnetometer). + * + * The gyro and accelerometer should only need to be calibrated once, but the magnetometer will need to be recalibrated + * every time the orientation of ferrous metals around the IMU changes (e.g. when it is put into a new enclosure). + * + * The new calibration will not be saved in flash until you call saveCalibration(). + * + * @param calibrateAccel Whether to calibrate the accelerometer. + * @param calibrateGyro Whether to calibrate the gyro. + * @param calibrateMag Whether to calibrate the magnetometer. + */ + void startCalibration(bool calibrateAccel, bool calibrateGyro, bool calibrateMag); + + /** + * Saves the calibration started with startCalibration() and ends the calibration. + * You will want to call this once the status bits read as "accuracy high". + * + * WARNING: if you paid for a factory calibrated IMU, then this WILL OVERWRITE THE FACTORY CALIBRATION in whatever sensors + * are being calibrated. Use with caution! + */ + void saveCalibration(); + + // Report functions + //----------------------------------------------------------------------------------------------------------------- + + /** + * Checks for new data packets queued on the IMU. + * If there are packets queued, receives all of them and updates + * the class variables with the results. + * + * @return true iff new data was received + */ + bool updateData(); + + + /** + * Gets the status of a report as a 2 bit number. + * per SH-2 section 6.5.1, this is interpreted as: <br> + * 0 - unreliable <br> + * 1 - accuracy low <br> + * 2 - accuracy medium <br> + * 3 - accuracy high <br> + * of course, these are only updated if a given report is enabled. + * @param report + * @return + */ + uint8_t getReportStatus(Report report); + + + /** + * Enable a data report from the IMU. Look at the comments above to see what the reports do. + * + * @param timeBetweenReports time in milliseconds between data updates. + */ + void enableReport(Report report, uint16_t timeBetweenReports); + +private: + + // internal utility functions + //----------------------------------------------------------------------------------------------------------------- + + /** + * Processes the packet currently stored in the buffer, and updates class variables to reflect the data it contains + */ + void processPacket(); + + /** + * Processes the sensor data packet currently stored in the buffer. + * Only called from processPacket() + */ + void parseSensorDataPacket(); + + /** + * Call to wait for a packet with the given parameters to come in. + * + * @param channel Channel of the packet + * @param reportID Report ID (first data byte) of the packet + * @param timeout how long to wait for the packet + * @return true if the packet has been received, false if it timed out + */ + bool waitForPacket(int channel, uint8_t reportID, float timeout = .125f); + + /** + * Given a Q value, converts fixed point floating to regular floating point number. + * @param fixedPointValue + * @param qPoint + * @return + */ + float qToFloat(int16_t fixedPointValue, uint8_t qPoint); + + /** + * Given a floating point value and a Q point, convert to Q + * See https://en.wikipedia.org/wiki/Q_(number_format) + * @param qFloat + * @param qPoint + * @return + */ + int16_t floatToQ(float qFloat, uint8_t qPoint); + + /** + * Tell the sensor to do a command. + * See SH-2 Reference Manual section 6.3.8 page 42, Command request + * The caller is expected to set shtpData 3 though 11 prior to calling + */ + void sendCommand(uint8_t command); + + /** + * Given a sensor's report ID, this tells the BNO080 to begin reporting the values. + * + * @param reportID + * @param timeBetweenReports + * @param specificConfig the specific config word. Useful for personal activity classifier. + */ + void setFeatureCommand(uint8_t reportID, uint16_t timeBetweenReports, uint32_t specificConfig = 0); + + /** + * Reads a packet from the IMU and stores it in the class variables. + * + * @param timeout how long to wait for there to be a packet + * + * @return whether a packet was recieved. + */ + bool receivePacket(float timeout=.2f); + + /** + * Sends the current shtpData contents to the BNO. It's a good idea to disable interrupts before you call this. + * + * @param channelNumber the channel to send on + * @param dataLength How many bits of shtpData to send + * @return + */ + bool sendPacket(uint8_t channelNumber, uint8_t dataLength); + + /** + * Prints the current shtp packet stored in the buffer. + * @param length + */ + void printPacket(); + + /** + * Erases the current SHTP packet buffer so new data can be written + */ + void zeroBuffer(); + +}; + + +#endif //HAMSTER_BNO080_H