/* Source: https://blog.naver.com/ysahn2k/221410891895 References: . MadgwickAHRS Filter Algorithm http://x-io.co.uk/open-source-imu-and-ahrs-algorithms/ . Jeff Rowberg's MPU6050 https://github.com/jrowberg/i2cdevlib . Kris Winer's MPU6050 https://github.com/kriswiner/MPU6050 . Davide Gironi's AVR atmega MPU6050 http://davidegironi.blogspot.com/2013/02/avr-atmega-mpu6050-gyroscope-and.html#.W7zM7mgzaUk */ //--------------------------------------------------------------------------------------------------- // Header files #include #include //--------------------------------------------------------------------------------------------------- // Definitions // Definitions referenced Jeff Rowberg's MPU6050.h #define MPU6050_ADDRESS_AD0_LOW 0x68 // address pin low (GND), default for InvenSense evaluation board #define MPU6050_ADDRESS_AD0_HIGH 0x69 // address pin high (VCC) #define MPU6050_DEFAULT_ADDRESS MPU6050_ADDRESS_AD0_LOW #define MPU6050_RA_XG_OFFS_TC 0x00 //[7] PWR_MODE, [6:1] XG_OFFS_TC, [0] OTP_BNK_VLD #define MPU6050_RA_YG_OFFS_TC 0x01 //[7] PWR_MODE, [6:1] YG_OFFS_TC, [0] OTP_BNK_VLD #define MPU6050_RA_ZG_OFFS_TC 0x02 //[7] PWR_MODE, [6:1] ZG_OFFS_TC, [0] OTP_BNK_VLD #define MPU6050_RA_X_FINE_GAIN 0x03 //[7:0] X_FINE_GAIN #define MPU6050_RA_Y_FINE_GAIN 0x04 //[7:0] Y_FINE_GAIN #define MPU6050_RA_Z_FINE_GAIN 0x05 //[7:0] Z_FINE_GAIN #define MPU6050_RA_XA_OFFS_H 0x06 //[15:0] XA_OFFS #define MPU6050_RA_XA_OFFS_L_TC 0x07 #define MPU6050_RA_YA_OFFS_H 0x08 //[15:0] YA_OFFS #define MPU6050_RA_YA_OFFS_L_TC 0x09 #define MPU6050_RA_ZA_OFFS_H 0x0A //[15:0] ZA_OFFS #define MPU6050_RA_ZA_OFFS_L_TC 0x0B #define MPU6050_RA_SELF_TEST_X 0x0D //[7:5] XA_TEST[4-2], [4:0] XG_TEST[4-0] #define MPU6050_RA_SELF_TEST_Y 0x0E //[7:5] YA_TEST[4-2], [4:0] YG_TEST[4-0] #define MPU6050_RA_SELF_TEST_Z 0x0F //[7:5] ZA_TEST[4-2], [4:0] ZG_TEST[4-0] #define MPU6050_RA_SELF_TEST_A 0x10 //[5:4] XA_TEST[1-0], [3:2] YA_TEST[1-0], [1:0] ZA_TEST[1-0] #define MPU6050_RA_XG_OFFS_USRH 0x13 //[15:0] XG_OFFS_USR #define MPU6050_RA_XG_OFFS_USRL 0x14 #define MPU6050_RA_YG_OFFS_USRH 0x15 //[15:0] YG_OFFS_USR #define MPU6050_RA_YG_OFFS_USRL 0x16 #define MPU6050_RA_ZG_OFFS_USRH 0x17 //[15:0] ZG_OFFS_USR #define MPU6050_RA_ZG_OFFS_USRL 0x18 #define MPU6050_RA_SMPLRT_DIV 0x19 #define MPU6050_RA_CONFIG 0x1A #define MPU6050_RA_GYRO_CONFIG 0x1B #define MPU6050_RA_ACCEL_CONFIG 0x1C #define MPU6050_RA_FF_THR 0x1D #define MPU6050_RA_FF_DUR 0x1E #define MPU6050_RA_MOT_THR 0x1F #define MPU6050_RA_MOT_DUR 0x20 #define MPU6050_RA_ZRMOT_THR 0x21 #define MPU6050_RA_ZRMOT_DUR 0x22 #define MPU6050_RA_FIFO_EN 0x23 #define MPU6050_RA_I2C_MST_CTRL 0x24 #define MPU6050_RA_I2C_SLV0_ADDR 0x25 #define MPU6050_RA_I2C_SLV0_REG 0x26 #define MPU6050_RA_I2C_SLV0_CTRL 0x27 #define MPU6050_RA_I2C_SLV1_ADDR 0x28 #define MPU6050_RA_I2C_SLV1_REG 0x29 #define MPU6050_RA_I2C_SLV1_CTRL 0x2A #define MPU6050_RA_I2C_SLV2_ADDR 0x2B #define MPU6050_RA_I2C_SLV2_REG 0x2C #define MPU6050_RA_I2C_SLV2_CTRL 0x2D #define MPU6050_RA_I2C_SLV3_ADDR 0x2E #define MPU6050_RA_I2C_SLV3_REG 0x2F #define MPU6050_RA_I2C_SLV3_CTRL 0x30 #define MPU6050_RA_I2C_SLV4_ADDR 0x31 #define MPU6050_RA_I2C_SLV4_REG 0x32 #define MPU6050_RA_I2C_SLV4_DO 0x33 #define MPU6050_RA_I2C_SLV4_CTRL 0x34 #define MPU6050_RA_I2C_SLV4_DI 0x35 #define MPU6050_RA_I2C_MST_STATUS 0x36 #define MPU6050_RA_INT_PIN_CFG 0x37 #define MPU6050_RA_INT_ENABLE 0x38 #define MPU6050_RA_DMP_INT_STATUS 0x39 #define MPU6050_RA_INT_STATUS 0x3A #define MPU6050_RA_ACCEL_XOUT_H 0x3B #define MPU6050_RA_ACCEL_XOUT_L 0x3C #define MPU6050_RA_ACCEL_YOUT_H 0x3D #define MPU6050_RA_ACCEL_YOUT_L 0x3E #define MPU6050_RA_ACCEL_ZOUT_H 0x3F #define MPU6050_RA_ACCEL_ZOUT_L 0x40 #define MPU6050_RA_TEMP_OUT_H 0x41 #define MPU6050_RA_TEMP_OUT_L 0x42 #define MPU6050_RA_GYRO_XOUT_H 0x43 #define MPU6050_RA_GYRO_XOUT_L 0x44 #define MPU6050_RA_GYRO_YOUT_H 0x45 #define MPU6050_RA_GYRO_YOUT_L 0x46 #define MPU6050_RA_GYRO_ZOUT_H 0x47 #define MPU6050_RA_GYRO_ZOUT_L 0x48 #define MPU6050_RA_EXT_SENS_DATA_00 0x49 #define MPU6050_RA_EXT_SENS_DATA_01 0x4A #define MPU6050_RA_EXT_SENS_DATA_02 0x4B #define MPU6050_RA_EXT_SENS_DATA_03 0x4C #define MPU6050_RA_EXT_SENS_DATA_04 0x4D #define MPU6050_RA_EXT_SENS_DATA_05 0x4E #define MPU6050_RA_EXT_SENS_DATA_06 0x4F #define MPU6050_RA_EXT_SENS_DATA_07 0x50 #define MPU6050_RA_EXT_SENS_DATA_08 0x51 #define MPU6050_RA_EXT_SENS_DATA_09 0x52 #define MPU6050_RA_EXT_SENS_DATA_10 0x53 #define MPU6050_RA_EXT_SENS_DATA_11 0x54 #define MPU6050_RA_EXT_SENS_DATA_12 0x55 #define MPU6050_RA_EXT_SENS_DATA_13 0x56 #define MPU6050_RA_EXT_SENS_DATA_14 0x57 #define MPU6050_RA_EXT_SENS_DATA_15 0x58 #define MPU6050_RA_EXT_SENS_DATA_16 0x59 #define MPU6050_RA_EXT_SENS_DATA_17 0x5A #define MPU6050_RA_EXT_SENS_DATA_18 0x5B #define MPU6050_RA_EXT_SENS_DATA_19 0x5C #define MPU6050_RA_EXT_SENS_DATA_20 0x5D #define MPU6050_RA_EXT_SENS_DATA_21 0x5E #define MPU6050_RA_EXT_SENS_DATA_22 0x5F #define MPU6050_RA_EXT_SENS_DATA_23 0x60 #define MPU6050_RA_MOT_DETECT_STATUS 0x61 #define MPU6050_RA_I2C_SLV0_DO 0x63 #define MPU6050_RA_I2C_SLV1_DO 0x64 #define MPU6050_RA_I2C_SLV2_DO 0x65 #define MPU6050_RA_I2C_SLV3_DO 0x66 #define MPU6050_RA_I2C_MST_DELAY_CTRL 0x67 #define MPU6050_RA_SIGNAL_PATH_RESET 0x68 #define MPU6050_RA_MOT_DETECT_CTRL 0x69 #define MPU6050_RA_USER_CTRL 0x6A #define MPU6050_RA_PWR_MGMT_1 0x6B #define MPU6050_RA_PWR_MGMT_2 0x6C #define MPU6050_RA_BANK_SEL 0x6D #define MPU6050_RA_MEM_START_ADDR 0x6E #define MPU6050_RA_MEM_R_W 0x6F #define MPU6050_RA_DMP_CFG_1 0x70 #define MPU6050_RA_DMP_CFG_2 0x71 #define MPU6050_RA_FIFO_COUNTH 0x72 #define MPU6050_RA_FIFO_COUNTL 0x73 #define MPU6050_RA_FIFO_R_W 0x74 #define MPU6050_RA_WHO_AM_I 0x75 #define MPU6050_SELF_TEST_XA_1_BIT 0x07 #define MPU6050_SELF_TEST_XA_1_LENGTH 0x03 #define MPU6050_SELF_TEST_XA_2_BIT 0x05 #define MPU6050_SELF_TEST_XA_2_LENGTH 0x02 #define MPU6050_SELF_TEST_YA_1_BIT 0x07 #define MPU6050_SELF_TEST_YA_1_LENGTH 0x03 #define MPU6050_SELF_TEST_YA_2_BIT 0x03 #define MPU6050_SELF_TEST_YA_2_LENGTH 0x02 #define MPU6050_SELF_TEST_ZA_1_BIT 0x07 #define MPU6050_SELF_TEST_ZA_1_LENGTH 0x03 #define MPU6050_SELF_TEST_ZA_2_BIT 0x01 #define MPU6050_SELF_TEST_ZA_2_LENGTH 0x02 #define MPU6050_SELF_TEST_XG_1_BIT 0x04 #define MPU6050_SELF_TEST_XG_1_LENGTH 0x05 #define MPU6050_SELF_TEST_YG_1_BIT 0x04 #define MPU6050_SELF_TEST_YG_1_LENGTH 0x05 #define MPU6050_SELF_TEST_ZG_1_BIT 0x04 #define MPU6050_SELF_TEST_ZG_1_LENGTH 0x05 #define MPU6050_TC_PWR_MODE_BIT 7 #define MPU6050_TC_OFFSET_BIT 6 #define MPU6050_TC_OFFSET_LENGTH 6 #define MPU6050_TC_OTP_BNK_VLD_BIT 0 #define MPU6050_VDDIO_LEVEL_VLOGIC 0 #define MPU6050_VDDIO_LEVEL_VDD 1 #define MPU6050_CFG_EXT_SYNC_SET_BIT 5 #define MPU6050_CFG_EXT_SYNC_SET_LENGTH 3 #define MPU6050_CFG_DLPF_CFG_BIT 2 #define MPU6050_CFG_DLPF_CFG_LENGTH 3 #define MPU6050_EXT_SYNC_DISABLED 0x0 #define MPU6050_EXT_SYNC_TEMP_OUT_L 0x1 #define MPU6050_EXT_SYNC_GYRO_XOUT_L 0x2 #define MPU6050_EXT_SYNC_GYRO_YOUT_L 0x3 #define MPU6050_EXT_SYNC_GYRO_ZOUT_L 0x4 #define MPU6050_EXT_SYNC_ACCEL_XOUT_L 0x5 #define MPU6050_EXT_SYNC_ACCEL_YOUT_L 0x6 #define MPU6050_EXT_SYNC_ACCEL_ZOUT_L 0x7 #define MPU6050_DLPF_BW_256 0x00 #define MPU6050_DLPF_BW_188 0x01 #define MPU6050_DLPF_BW_98 0x02 #define MPU6050_DLPF_BW_42 0x03 #define MPU6050_DLPF_BW_20 0x04 #define MPU6050_DLPF_BW_10 0x05 #define MPU6050_DLPF_BW_5 0x06 #define MPU6050_GCONFIG_FS_SEL_BIT 4 #define MPU6050_GCONFIG_FS_SEL_LENGTH 2 #define MPU6050_GYRO_FS_250 0x00 #define MPU6050_GYRO_FS_500 0x01 #define MPU6050_GYRO_FS_1000 0x02 #define MPU6050_GYRO_FS_2000 0x03 #define MPU6050_ACONFIG_XA_ST_BIT 7 #define MPU6050_ACONFIG_YA_ST_BIT 6 #define MPU6050_ACONFIG_ZA_ST_BIT 5 #define MPU6050_ACONFIG_AFS_SEL_BIT 4 #define MPU6050_ACONFIG_AFS_SEL_LENGTH 2 #define MPU6050_ACONFIG_ACCEL_HPF_BIT 2 #define MPU6050_ACONFIG_ACCEL_HPF_LENGTH 3 #define MPU6050_ACCEL_FS_2 0x00 #define MPU6050_ACCEL_FS_4 0x01 #define MPU6050_ACCEL_FS_8 0x02 #define MPU6050_ACCEL_FS_16 0x03 #define MPU6050_DHPF_RESET 0x00 #define MPU6050_DHPF_5 0x01 #define MPU6050_DHPF_2P5 0x02 #define MPU6050_DHPF_1P25 0x03 #define MPU6050_DHPF_0P63 0x04 #define MPU6050_DHPF_HOLD 0x07 #define MPU6050_TEMP_FIFO_EN_BIT 7 #define MPU6050_XG_FIFO_EN_BIT 6 #define MPU6050_YG_FIFO_EN_BIT 5 #define MPU6050_ZG_FIFO_EN_BIT 4 #define MPU6050_ACCEL_FIFO_EN_BIT 3 #define MPU6050_SLV2_FIFO_EN_BIT 2 #define MPU6050_SLV1_FIFO_EN_BIT 1 #define MPU6050_SLV0_FIFO_EN_BIT 0 #define MPU6050_MULT_MST_EN_BIT 7 #define MPU6050_WAIT_FOR_ES_BIT 6 #define MPU6050_SLV_3_FIFO_EN_BIT 5 #define MPU6050_I2C_MST_P_NSR_BIT 4 #define MPU6050_I2C_MST_CLK_BIT 3 #define MPU6050_I2C_MST_CLK_LENGTH 4 #define MPU6050_CLOCK_DIV_348 0x0 #define MPU6050_CLOCK_DIV_333 0x1 #define MPU6050_CLOCK_DIV_320 0x2 #define MPU6050_CLOCK_DIV_308 0x3 #define MPU6050_CLOCK_DIV_296 0x4 #define MPU6050_CLOCK_DIV_286 0x5 #define MPU6050_CLOCK_DIV_276 0x6 #define MPU6050_CLOCK_DIV_267 0x7 #define MPU6050_CLOCK_DIV_258 0x8 #define MPU6050_CLOCK_DIV_500 0x9 #define MPU6050_CLOCK_DIV_471 0xA #define MPU6050_CLOCK_DIV_444 0xB #define MPU6050_CLOCK_DIV_421 0xC #define MPU6050_CLOCK_DIV_400 0xD #define MPU6050_CLOCK_DIV_381 0xE #define MPU6050_CLOCK_DIV_364 0xF #define MPU6050_I2C_SLV_RW_BIT 7 #define MPU6050_I2C_SLV_ADDR_BIT 6 #define MPU6050_I2C_SLV_ADDR_LENGTH 7 #define MPU6050_I2C_SLV_EN_BIT 7 #define MPU6050_I2C_SLV_BYTE_SW_BIT 6 #define MPU6050_I2C_SLV_REG_DIS_BIT 5 #define MPU6050_I2C_SLV_GRP_BIT 4 #define MPU6050_I2C_SLV_LEN_BIT 3 #define MPU6050_I2C_SLV_LEN_LENGTH 4 #define MPU6050_I2C_SLV4_RW_BIT 7 #define MPU6050_I2C_SLV4_ADDR_BIT 6 #define MPU6050_I2C_SLV4_ADDR_LENGTH 7 #define MPU6050_I2C_SLV4_EN_BIT 7 #define MPU6050_I2C_SLV4_INT_EN_BIT 6 #define MPU6050_I2C_SLV4_REG_DIS_BIT 5 #define MPU6050_I2C_SLV4_MST_DLY_BIT 4 #define MPU6050_I2C_SLV4_MST_DLY_LENGTH 5 #define MPU6050_MST_PASS_THROUGH_BIT 7 #define MPU6050_MST_I2C_SLV4_DONE_BIT 6 #define MPU6050_MST_I2C_LOST_ARB_BIT 5 #define MPU6050_MST_I2C_SLV4_NACK_BIT 4 #define MPU6050_MST_I2C_SLV3_NACK_BIT 3 #define MPU6050_MST_I2C_SLV2_NACK_BIT 2 #define MPU6050_MST_I2C_SLV1_NACK_BIT 1 #define MPU6050_MST_I2C_SLV0_NACK_BIT 0 #define MPU6050_INTCFG_INT_LEVEL_BIT 7 #define MPU6050_INTCFG_INT_OPEN_BIT 6 #define MPU6050_INTCFG_LATCH_INT_EN_BIT 5 #define MPU6050_INTCFG_INT_RD_CLEAR_BIT 4 #define MPU6050_INTCFG_FSYNC_INT_LEVEL_BIT 3 #define MPU6050_INTCFG_FSYNC_INT_EN_BIT 2 #define MPU6050_INTCFG_I2C_BYPASS_EN_BIT 1 #define MPU6050_INTCFG_CLKOUT_EN_BIT 0 #define MPU6050_INTMODE_ACTIVEHIGH 0x00 #define MPU6050_INTMODE_ACTIVELOW 0x01 #define MPU6050_INTDRV_PUSHPULL 0x00 #define MPU6050_INTDRV_OPENDRAIN 0x01 #define MPU6050_INTLATCH_50USPULSE 0x00 #define MPU6050_INTLATCH_WAITCLEAR 0x01 #define MPU6050_INTCLEAR_STATUSREAD 0x00 #define MPU6050_INTCLEAR_ANYREAD 0x01 #define MPU6050_INTERRUPT_FF_BIT 7 #define MPU6050_INTERRUPT_MOT_BIT 6 #define MPU6050_INTERRUPT_ZMOT_BIT 5 #define MPU6050_INTERRUPT_FIFO_OFLOW_BIT 4 #define MPU6050_INTERRUPT_I2C_MST_INT_BIT 3 #define MPU6050_INTERRUPT_PLL_RDY_INT_BIT 2 #define MPU6050_INTERRUPT_DMP_INT_BIT 1 #define MPU6050_INTERRUPT_DATA_RDY_BIT 0 // TODO: figure out what these actually do // UMPL source code is not very obivous #define MPU6050_DMPINT_5_BIT 5 #define MPU6050_DMPINT_4_BIT 4 #define MPU6050_DMPINT_3_BIT 3 #define MPU6050_DMPINT_2_BIT 2 #define MPU6050_DMPINT_1_BIT 1 #define MPU6050_DMPINT_0_BIT 0 #define MPU6050_MOTION_MOT_XNEG_BIT 7 #define MPU6050_MOTION_MOT_XPOS_BIT 6 #define MPU6050_MOTION_MOT_YNEG_BIT 5 #define MPU6050_MOTION_MOT_YPOS_BIT 4 #define MPU6050_MOTION_MOT_ZNEG_BIT 3 #define MPU6050_MOTION_MOT_ZPOS_BIT 2 #define MPU6050_MOTION_MOT_ZRMOT_BIT 0 #define MPU6050_DELAYCTRL_DELAY_ES_SHADOW_BIT 7 #define MPU6050_DELAYCTRL_I2C_SLV4_DLY_EN_BIT 4 #define MPU6050_DELAYCTRL_I2C_SLV3_DLY_EN_BIT 3 #define MPU6050_DELAYCTRL_I2C_SLV2_DLY_EN_BIT 2 #define MPU6050_DELAYCTRL_I2C_SLV1_DLY_EN_BIT 1 #define MPU6050_DELAYCTRL_I2C_SLV0_DLY_EN_BIT 0 #define MPU6050_PATHRESET_GYRO_RESET_BIT 2 #define MPU6050_PATHRESET_ACCEL_RESET_BIT 1 #define MPU6050_PATHRESET_TEMP_RESET_BIT 0 #define MPU6050_DETECT_ACCEL_ON_DELAY_BIT 5 #define MPU6050_DETECT_ACCEL_ON_DELAY_LENGTH 2 #define MPU6050_DETECT_FF_COUNT_BIT 3 #define MPU6050_DETECT_FF_COUNT_LENGTH 2 #define MPU6050_DETECT_MOT_COUNT_BIT 1 #define MPU6050_DETECT_MOT_COUNT_LENGTH 2 #define MPU6050_DETECT_DECREMENT_RESET 0x0 #define MPU6050_DETECT_DECREMENT_1 0x1 #define MPU6050_DETECT_DECREMENT_2 0x2 #define MPU6050_DETECT_DECREMENT_4 0x3 #define MPU6050_USERCTRL_DMP_EN_BIT 7 #define MPU6050_USERCTRL_FIFO_EN_BIT 6 #define MPU6050_USERCTRL_I2C_MST_EN_BIT 5 #define MPU6050_USERCTRL_I2C_IF_DIS_BIT 4 #define MPU6050_USERCTRL_DMP_RESET_BIT 3 #define MPU6050_USERCTRL_FIFO_RESET_BIT 2 #define MPU6050_USERCTRL_I2C_MST_RESET_BIT 1 #define MPU6050_USERCTRL_SIG_COND_RESET_BIT 0 #define MPU6050_PWR1_DEVICE_RESET_BIT 7 #define MPU6050_PWR1_SLEEP_BIT 6 #define MPU6050_PWR1_CYCLE_BIT 5 #define MPU6050_PWR1_TEMP_DIS_BIT 3 #define MPU6050_PWR1_CLKSEL_BIT 2 #define MPU6050_PWR1_CLKSEL_LENGTH 3 #define MPU6050_CLOCK_INTERNAL 0x00 #define MPU6050_CLOCK_PLL_XGYRO 0x01 #define MPU6050_CLOCK_PLL_YGYRO 0x02 #define MPU6050_CLOCK_PLL_ZGYRO 0x03 #define MPU6050_CLOCK_PLL_EXT32K 0x04 #define MPU6050_CLOCK_PLL_EXT19M 0x05 #define MPU6050_CLOCK_KEEP_RESET 0x07 #define MPU6050_PWR2_LP_WAKE_CTRL_BIT 7 #define MPU6050_PWR2_LP_WAKE_CTRL_LENGTH 2 #define MPU6050_PWR2_STBY_XA_BIT 5 #define MPU6050_PWR2_STBY_YA_BIT 4 #define MPU6050_PWR2_STBY_ZA_BIT 3 #define MPU6050_PWR2_STBY_XG_BIT 2 #define MPU6050_PWR2_STBY_YG_BIT 1 #define MPU6050_PWR2_STBY_ZG_BIT 0 #define MPU6050_WAKE_FREQ_1P25 0x0 #define MPU6050_WAKE_FREQ_2P5 0x1 #define MPU6050_WAKE_FREQ_5 0x2 #define MPU6050_WAKE_FREQ_10 0x3 #define MPU6050_BANKSEL_PRFTCH_EN_BIT 6 #define MPU6050_BANKSEL_CFG_USER_BANK_BIT 5 #define MPU6050_BANKSEL_MEM_SEL_BIT 4 #define MPU6050_BANKSEL_MEM_SEL_LENGTH 5 #define MPU6050_WHO_AM_I_BIT 6 #define MPU6050_WHO_AM_I_LENGTH 6 #define MPU6050_DMP_MEMORY_BANKS 8 #define MPU6050_DMP_MEMORY_BANK_SIZE 256 #define MPU6050_DMP_MEMORY_CHUNK_SIZE 16 // For Quaternion function #define twoKpDef (2.0f * 0.5f) // 2 * proportional gain #define twoKiDef (2.0f * 0.0f) // 2 * integral gain // Transform raw data of accelerometer & gyroscope #define MPU6050_AXOFFSET -208 #define MPU6050_AYOFFSET 417 #define MPU6050_AZOFFSET 93 //#define MPU6050_AXOFFSET 0 //#define MPU6050_AYOFFSET 0 //#define MPU6050_AZOFFSET 0 //#define MPU6050_AXGAIN 16384.0 // AFS_SEL = 0, +/-2g, MPU6050_ACCEL_FS_2 //#define MPU6050_AYGAIN 16384.0 // AFS_SEL = 0, +/-2g, MPU6050_ACCEL_FS_2 //#define MPU6050_AZGAIN 16384.0 // AFS_SEL = 0, +/-2g, MPU6050_ACCEL_FS_2 //#define MPU6050_AXGAIN 8192.0 // AFS_SEL = 1, +/-4g, MPU6050_ACCEL_FS_4 //#define MPU6050_AYGAIN 8192.0 // AFS_SEL = 1, +/-4g, MPU6050_ACCEL_FS_4 //#define MPU6050_AZGAIN 8192.0 // AFS_SEL = 1, +/-4g, MPU6050_ACCEL_FS_4 #define MPU6050_AXGAIN 4096.0 // AFS_SEL = 2, +/-8g, MPU6050_ACCEL_FS_8 #define MPU6050_AYGAIN 4096.0 // AFS_SEL = 2, +/-8g, MPU6050_ACCEL_FS_8 #define MPU6050_AZGAIN 4096.0 // AFS_SEL = 2, +/-8g, MPU6050_ACCEL_FS_8 //#define MPU6050_AXGAIN 2048.0 // AFS_SEL = 3, +/-16g, MPU6050_ACCEL_FS_16 //#define MPU6050_AYGAIN 2048.0 // AFS_SEL = 3, +/-16g, MPU6050_ACCEL_FS_16 //#define MPU6050_AZGAIN 2048.0 // AFS_SEL = 3, +/-16g, MPU6050_ACCEL_FS_16 #define MPU6050_GXOFFSET 0 #define MPU6050_GYOFFSET 2 #define MPU6050_GZOFFSET 3 //#define MPU6050_GXOFFSET 0 //#define MPU6050_GYOFFSET 0 //#define MPU6050_GZOFFSET 0 //#define MPU6050_GXGAIN 131.072 // FS_SEL = 0, +/-250degree/s, MPU6050_GYRO_FS_250 //#define MPU6050_GYGAIN 131.072 // FS_SEL = 0, +/-250degree/s, MPU6050_GYRO_FS_250 //#define MPU6050_GZGAIN 131.072 // FS_SEL = 0, +/-250degree/s, MPU6050_GYRO_FS_250 //#define MPU6050_GXGAIN 65.536 // FS_SEL = 1, +/-500degree/s, MPU6050_GYRO_FS_500 //#define MPU6050_GYGAIN 65.536 // FS_SEL = 1, +/-500degree/s, MPU6050_GYRO_FS_500 //#define MPU6050_GZGAIN 65.536 // FS_SEL = 1, +/-500degree/s, MPU6050_GYRO_FS_500 //#define MPU6050_GXGAIN 32.768 // FS_SEL = 2, +/-1000degree/s, MPU6050_GYRO_FS_1000 //#define MPU6050_GYGAIN 32.768 // FS_SEL = 2, +/-1000degree/s, MPU6050_GYRO_FS_1000 //#define MPU6050_GZGAIN 32.768 // FS_SEL = 2, +/-1000degree/s, MPU6050_GYRO_FS_1000 #define MPU6050_GXGAIN 16.384 // FS_SEL = 3, +/-2000degree/s, MPU6050_GYRO_FS_2000 #define MPU6050_GYGAIN 16.384 // FS_SEL = 3, +/-2000degree/s, MPU6050_GYRO_FS_2000 #define MPU6050_GZGAIN 16.384 // FS_SEL = 3, +/-2000degree/s, MPU6050_GYRO_FS_2000 // Blinking LED #define LED_PIN 22 // For Blinking LED #define SDA 0 #define SCL 4 //--------------------------------------------------------------------------------------------------- // Variable definitions volatile float twoKp = twoKpDef; // 2 * proportional gain (Kp) volatile float twoKi = twoKiDef; // 2 * integral gain (Ki) volatile float q0 = 1.0f, q1 = 0.0f, q2 = 0.0f, q3 = 0.0f; // quaternion of sensor frame relative to auxiliary frame volatile float integralFBx = 0.0f, integralFBy = 0.0f, integralFBz = 0.0f; // integral error terms scaled by Ki long sampling_timer; int16_t AcX, AcY, AcZ, Tmp, GyX, GyY, GyZ; float axg, ayg, azg, gxrs, gyrs, gzrs; float roll, pitch, yaw; float SelfTest[6]; float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer float sampleFreq = 0.0f; // integration interval for both filter schemes uint32_t lastUpdate = 0, firstUpdate = 0; // used to calculate integration interval uint32_t Now = 0; // used to calculate integration interval bool blinkState = false; // LED Bliking for Pin13 void setup() { Wire.begin(SDA, SCL, 400000); Serial.begin(115200); // Self Test MPU6050SelfTest(SelfTest); // Calibrate MPU6050 //calibrateMPU6050(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers // Initialize MPU6050 MPU6050_Init(); // Configure LED for output pinMode(LED_PIN, OUTPUT); // Sampling Timer sampling_timer = micros(); } void loop() { // Get raw data mpu6050_GetData(); // Update raw data to Quaternion form mpu6050_updateQuaternion(); Now = micros(); sampleFreq = (1000000.0f / (Now - lastUpdate)); // set integration time by time elapsed since last filter update lastUpdate = Now; //compute data MahonyAHRSupdateIMU(gxrs, gyrs, gzrs, axg, ayg, azg); // Value of Roll, Pitch, Yaw mpu6050_getRollPitchYaw(); // Print Roll, Pitch, Yaw to Serial Monitor Serial.print(roll); Serial.print("\t"); Serial.print(pitch); Serial.print("\t"); Serial.println(yaw); // Sampling Timer //while(micros() - sampling_timer < 3950); // //sampling_timer = micros(); //Reset the sampling timer // Blink LED to indicate activity blinkState = !blinkState; digitalWrite(LED_PIN, blinkState); } void MPU6050_Init(){ // MPU6050 Initializing & Reset writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_PWR_MGMT_1, 0x00); // set to zero (wakes up the MPU-6050) // MPU6050 Clock Type writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_PWR_MGMT_1, 0x01); // Selection Clock 'PLL with X axis gyroscope reference' // MPU6050 Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV) for DMP //writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_SMPLRT_DIV, 0x00); // Default is 1KHz // example 0x04 is 200Hz // MPU6050 Gyroscope Configuration Setting /* Wire.write(0x00); // FS_SEL=0, Full Scale Range = +/- 250 [degree/sec] Wire.write(0x08); // FS_SEL=1, Full Scale Range = +/- 500 [degree/sec] Wire.write(0x10); // FS_SEL=2, Full Scale Range = +/- 1000 [degree/sec] Wire.write(0x18); // FS_SEL=3, Full Scale Range = +/- 2000 [degree/sec] */ writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_GYRO_CONFIG, 0x18); // FS_SEL=3 // MPU6050 Accelerometer Configuration Setting /* Wire.write(0x00); // AFS_SEL=0, Full Scale Range = +/- 2 [g] Wire.write(0x08); // AFS_SEL=1, Full Scale Range = +/- 4 [g] Wire.write(0x10); // AFS_SEL=2, Full Scale Range = +/- 8 [g] Wire.write(0x18); // AFS_SEL=3, Full Scale Range = +/- 10 [g] */ writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ACCEL_CONFIG, 0x10); // AFS_SEL=2 // MPU6050 DLPF(Digital Low Pass Filter) /*Wire.write(0x00); // Accel BW 260Hz, Delay 0ms / Gyro BW 256Hz, Delay 0.98ms, Fs 8KHz Wire.write(0x01); // Accel BW 184Hz, Delay 2ms / Gyro BW 188Hz, Delay 1.9ms, Fs 1KHz Wire.write(0x02); // Accel BW 94Hz, Delay 3ms / Gyro BW 98Hz, Delay 2.8ms, Fs 1KHz Wire.write(0x03); // Accel BW 44Hz, Delay 4.9ms / Gyro BW 42Hz, Delay 4.8ms, Fs 1KHz Wire.write(0x04); // Accel BW 21Hz, Delay 8.5ms / Gyro BW 20Hz, Delay 8.3ms, Fs 1KHz Wire.write(0x05); // Accel BW 10Hz, Delay 13.8ms / Gyro BW 10Hz, Delay 13.4ms, Fs 1KHz Wire.write(0x06); // Accel BW 5Hz, Delay 19ms / Gyro BW 5Hz, Delay 18.6ms, Fs 1KHz */ writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_CONFIG, 0x00); //Accel BW 260Hz, Delay 0ms / Gyro BW 256Hz, Delay 0.98ms, Fs 8KHz } void mpu6050_GetData() { uint8_t data_org[14]; // original data of accelerometer and gyro readBytes(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ACCEL_XOUT_H, 14, &data_org[0]); AcX = data_org[0] << 8 | data_org[1]; // 0x3B (ACCEL_XOUT_H) & 0x3C (ACCEL_XOUT_L) AcY = data_org[2] << 8 | data_org[3]; // 0x3D (ACCEL_YOUT_H) & 0x3E (ACCEL_YOUT_L) AcZ = data_org[4] << 8 | data_org[5]; // 0x3F (ACCEL_ZOUT_H) & 0x40 (ACCEL_ZOUT_L) Tmp = data_org[6] << 8 | data_org[7]; // 0x41 (TEMP_OUT_H) & 0x42 (TEMP_OUT_L) GyX = data_org[8] << 8 | data_org[9]; // 0x43 (GYRO_XOUT_H) & 0x44 (GYRO_XOUT_L) GyY = data_org[10] << 8 | data_org[11]; // 0x45 (GYRO_YOUT_H) & 0x46 (GYRO_YOUT_L) GyZ = data_org[12] << 8 | data_org[13]; // 0x47 (GYRO_ZOUT_H) & 0x48 (GYRO_ZOUT_L) } void mpu6050_updateQuaternion() { axg = (float)(AcX - MPU6050_AXOFFSET) / MPU6050_AXGAIN; ayg = (float)(AcY - MPU6050_AYOFFSET) / MPU6050_AYGAIN; azg = (float)(AcZ - MPU6050_AZOFFSET) / MPU6050_AZGAIN; gxrs = (float)(GyX - MPU6050_GXOFFSET) / MPU6050_GXGAIN * 0.01745329; //degree to radians gyrs = (float)(GyY - MPU6050_GYOFFSET) / MPU6050_GYGAIN * 0.01745329; //degree to radians gzrs = (float)(GyZ - MPU6050_GZOFFSET) / MPU6050_GZGAIN * 0.01745329; //degree to radians // Degree to Radians Pi / 180 = 0.01745329 0.01745329251994329576923690768489 } void MahonyAHRSupdateIMU(float gx, float gy, float gz, float ax, float ay, float az) { float norm; float halfvx, halfvy, halfvz; float halfex, halfey, halfez; float qa, qb, qc; // Compute feedback only if accelerometer measurement valid (avoids NaN in accelerometer normalisation) if(!((ax == 0.0f) && (ay == 0.0f) && (az == 0.0f))) { // Normalise accelerometer measurement norm = sqrt(ax * ax + ay * ay + az * az); ax /= norm; ay /= norm; az /= norm; // Estimated direction of gravity and vector perpendicular to magnetic flux halfvx = q1 * q3 - q0 * q2; halfvy = q0 * q1 + q2 * q3; halfvz = q0 * q0 - 0.5f + q3 * q3; // Error is sum of cross product between estimated and measured direction of gravity halfex = (ay * halfvz - az * halfvy); halfey = (az * halfvx - ax * halfvz); halfez = (ax * halfvy - ay * halfvx); // Compute and apply integral feedback if enabled if(twoKi > 0.0f) { integralFBx += twoKi * halfex * (1.0f / sampleFreq); // integral error scaled by Ki integralFBy += twoKi * halfey * (1.0f / sampleFreq); integralFBz += twoKi * halfez * (1.0f / sampleFreq); gx += integralFBx; // apply integral feedback gy += integralFBy; gz += integralFBz; } else { integralFBx = 0.0f; // prevent integral windup integralFBy = 0.0f; integralFBz = 0.0f; } // Apply proportional feedback gx += twoKp * halfex; gy += twoKp * halfey; gz += twoKp * halfez; } // Integrate rate of change of quaternion gx *= (0.5f * (1.0f / sampleFreq)); // pre-multiply common factors gy *= (0.5f * (1.0f / sampleFreq)); gz *= (0.5f * (1.0f / sampleFreq)); qa = q0; qb = q1; qc = q2; q0 += (-qb * gx - qc * gy - q3 * gz); q1 += (qa * gx + qc * gz - q3 * gy); q2 += (qa * gy - qb * gz + q3 * gx); q3 += (qa * gz + qb * gy - qc * gx); // Normalise quaternion norm = sqrt(q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3); q0 /= norm; q1 /= norm; q2 /= norm; q3 /= norm; } void mpu6050_getRollPitchYaw() { // yaw = atan2(2*q1*q2 - 2*q0*q3, 2*q0*q0 + 2*q1*q1 - 1) * 57.29577951; // pitch = -asin(2*q1*q3 + 2*q0*q2) * 57.29577951; // roll = atan2(2*q2*q3 - 2*q0*q1, 2*q0*q0 + 2*q3*q3 - 1) * 57.29577951; // roll = atan2(2*q0*q1 + 2*q2*q3, 1 - 2*q1*q1 - 2*q2*q2) * 57.29577951; // pitch = asin(2*q0*q2 - 2*q3*q1) * 57.29577951; // yaw = atan2(2*q0*q3 + 2*q1*q2, 1 - 2*q2*q2 - 2*q3*q3) * 57.29577951; yaw = -atan2(2.0f * (q1 * q2 + q0 * q3), q0 * q0 + q1 * q1 - q2 * q2 - q3 * q3) * 57.29577951; pitch = asin(2.0f * (q1 * q3 - q0 * q2)) * 57.29577951; roll = atan2(2.0f * (q0 * q1 + q2 * q3), q0 * q0 - q1 * q1 - q2 * q2 + q3 * q3) * 57.29577951; } void writeByte(uint8_t address, uint8_t subAddress, uint8_t data) { Wire.beginTransmission(address); // Initialize the Tx buffer Wire.write(subAddress); // Put slave register address in Tx buffer Wire.write(data); // Put data in Tx buffer Wire.endTransmission(); // Send the Tx buffer } // Accelerometer and gyroscope self test; check calibration wrt factory settings void MPU6050SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass { uint8_t rawData[4]; uint8_t selfTest[6]; float factoryTrim[6]; // Configure the accelerometer for self-test writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ACCEL_CONFIG, 0xF0); // Enable self test on all three axes and set accelerometer range to +/- 8 g writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s delay(250); // Delay a while to let the device execute the self-test rawData[0] = readByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_SELF_TEST_X); // X-axis self-test results rawData[1] = readByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_SELF_TEST_Y); // Y-axis self-test results rawData[2] = readByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_SELF_TEST_Z); // Z-axis self-test results rawData[3] = readByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_SELF_TEST_A); // Mixed-axis self-test results // Extract the acceleration test results first selfTest[0] = (rawData[0] >> 3) | (rawData[3] & 0x30) >> 4 ; // XA_TEST result is a five-bit unsigned integer selfTest[1] = (rawData[1] >> 3) | (rawData[3] & 0x0C) >> 2 ; // YA_TEST result is a five-bit unsigned integer selfTest[2] = (rawData[2] >> 3) | (rawData[3] & 0x03) ; // ZA_TEST result is a five-bit unsigned integer // Extract the gyration test results first selfTest[3] = rawData[0] & 0x1F ; // XG_TEST result is a five-bit unsigned integer selfTest[4] = rawData[1] & 0x1F ; // YG_TEST result is a five-bit unsigned integer selfTest[5] = rawData[2] & 0x1F ; // ZG_TEST result is a five-bit unsigned integer // Process results to allow final comparison with factory set values factoryTrim[0] = (4096.0*0.34)*(pow( (0.92/0.34) , (((float)selfTest[0] - 1.0)/30.0))); // FT[Xa] factory trim calculation factoryTrim[1] = (4096.0*0.34)*(pow( (0.92/0.34) , (((float)selfTest[1] - 1.0)/30.0))); // FT[Ya] factory trim calculation factoryTrim[2] = (4096.0*0.34)*(pow( (0.92/0.34) , (((float)selfTest[2] - 1.0)/30.0))); // FT[Za] factory trim calculation factoryTrim[3] = ( 25.0*131.0)*(pow( 1.046 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation factoryTrim[4] = (-25.0*131.0)*(pow( 1.046 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation factoryTrim[5] = ( 25.0*131.0)*(pow( 1.046 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation // Output self-test results and factory trim calculation if desired // Serial.println(selfTest[0]); Serial.println(selfTest[1]); Serial.println(selfTest[2]); // Serial.println(selfTest[3]); Serial.println(selfTest[4]); Serial.println(selfTest[5]); // Serial.println(factoryTrim[0]); Serial.println(factoryTrim[1]); Serial.println(factoryTrim[2]); // Serial.println(factoryTrim[3]); Serial.println(factoryTrim[4]); Serial.println(factoryTrim[5]); // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response // To get to percent, must multiply by 100 and subtract result from 100 for (int i = 0; i < 6; i++) { destination[i] = 100.0 + 100.0*((float)selfTest[i] - factoryTrim[i])/factoryTrim[i]; // Report percent differences } } // Function which accumulates gyro and accelerometer data after device initialization. It calculates the average // of the at-rest readings and then loads the resulting offsets into accelerometer and gyro bias registers. void calibrateMPU6050(float * dest1, float * dest2) { uint8_t data[12]; // data array to hold accelerometer and gyro x, y, z, data uint16_t ii, packet_count, fifo_count; int32_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0}; // reset device, reset all registers, clear gyro and accelerometer bias registers writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device delay(100); // get stable time source // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001 writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_PWR_MGMT_1, 0x01); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_PWR_MGMT_2, 0x00); delay(200); // Configure device for bias calculation writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_INT_ENABLE, 0x00); // Disable all interrupts writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_FIFO_EN, 0x00); // Disable FIFO writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_PWR_MGMT_1, 0x00); // Turn on internal clock source writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_I2C_MST_CTRL, 0x00); // Disable I2C master writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_USER_CTRL, 0x00); // Disable FIFO and I2C master modes writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_USER_CTRL, 0x0C); // Reset FIFO and DMP delay(15); // Configure MPU6050 gyro and accelerometer for bias calculation writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_CONFIG, 0x01); // Set low-pass filter to 188 Hz writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ACCEL_CONFIG, 0x00); // Set accelerometer full-scale to 2 g, maximum sensitivity uint16_t gyrosensitivity = 131; // = 131 LSB/degrees/sec uint16_t accelsensitivity = 16384; // = 16384 LSB/g // Configure FIFO to capture accelerometer and gyro data for bias calculation writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_USER_CTRL, 0x40); // Enable FIFO writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 1024 bytes in MPU-6050) delay(80); // accumulate 80 samples in 80 milliseconds = 960 bytes // At end of sample accumulation, turn off FIFO sensor read writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO readBytes(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_FIFO_COUNTH, 2, &data[0]); // read FIFO sample count fifo_count = ((uint16_t)data[0] << 8) | data[1]; packet_count = fifo_count/12;// How many sets of full gyro and accelerometer data for averaging for (ii = 0; ii < packet_count; ii++) { int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0}; readBytes(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_FIFO_R_W, 12, &data[0]); // read data for averaging accel_temp[0] = (int16_t) (((int16_t)data[0] << 8) | data[1] ) ; // Form signed 16-bit integer for each sample in FIFO accel_temp[1] = (int16_t) (((int16_t)data[2] << 8) | data[3] ) ; accel_temp[2] = (int16_t) (((int16_t)data[4] << 8) | data[5] ) ; gyro_temp[0] = (int16_t) (((int16_t)data[6] << 8) | data[7] ) ; gyro_temp[1] = (int16_t) (((int16_t)data[8] << 8) | data[9] ) ; gyro_temp[2] = (int16_t) (((int16_t)data[10] << 8) | data[11]) ; accel_bias[0] += (int32_t) accel_temp[0]; // Sum individual signed 16-bit biases to get accumulated signed 32-bit biases accel_bias[1] += (int32_t) accel_temp[1]; accel_bias[2] += (int32_t) accel_temp[2]; gyro_bias[0] += (int32_t) gyro_temp[0]; gyro_bias[1] += (int32_t) gyro_temp[1]; gyro_bias[2] += (int32_t) gyro_temp[2]; } accel_bias[0] /= (int32_t) packet_count; // Normalize sums to get average count biases accel_bias[1] /= (int32_t) packet_count; accel_bias[2] /= (int32_t) packet_count; gyro_bias[0] /= (int32_t) packet_count; gyro_bias[1] /= (int32_t) packet_count; gyro_bias[2] /= (int32_t) packet_count; if(accel_bias[2] > 0L) {accel_bias[2] -= (int32_t) accelsensitivity;} // Remove gravity from the z-axis accelerometer bias calculation else {accel_bias[2] += (int32_t) accelsensitivity;} // Construct the gyro biases for push to the hardware gyro bias registers, which are reset to zero upon device startup data[0] = (-gyro_bias[0]/4 >> 8) & 0xFF; // Divide by 4 to get 32.9 LSB per deg/s to conform to expected bias input format data[1] = (-gyro_bias[0]/4) & 0xFF; // Biases are additive, so change sign on calculated average gyro biases data[2] = (-gyro_bias[1]/4 >> 8) & 0xFF; data[3] = (-gyro_bias[1]/4) & 0xFF; data[4] = (-gyro_bias[2]/4 >> 8) & 0xFF; data[5] = (-gyro_bias[2]/4) & 0xFF; // Push gyro biases to hardware registers writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_XG_OFFS_USRH, data[0]);// might not be supported in MPU6050 writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_XG_OFFS_USRL, data[1]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_YG_OFFS_USRH, data[2]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_YG_OFFS_USRL, data[3]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ZG_OFFS_USRH, data[4]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ZG_OFFS_USRL, data[5]); dest1[0] = (float) gyro_bias[0]/(float) gyrosensitivity; // construct gyro bias in deg/s for later manual subtraction dest1[1] = (float) gyro_bias[1]/(float) gyrosensitivity; dest1[2] = (float) gyro_bias[2]/(float) gyrosensitivity; // Construct the accelerometer biases for push to the hardware accelerometer bias registers. These registers contain // factory trim values which must be added to the calculated accelerometer biases; on boot up these registers will hold // non-zero values. In addition, bit 0 of the lower byte must be preserved since it is used for temperature // compensation calculations. Accelerometer bias registers expect bias input as 2048 LSB per g, so that // the accelerometer biases calculated above must be divided by 8. int32_t accel_bias_reg[3] = {0, 0, 0}; // A place to hold the factory accelerometer trim biases readBytes(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_XA_OFFS_H, 2, &data[0]); // Read factory accelerometer trim values accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1]; readBytes(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_YA_OFFS_H, 2, &data[0]); accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1]; readBytes(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ZA_OFFS_H, 2, &data[0]); accel_bias_reg[2] = (int16_t) ((int16_t)data[0] << 8) | data[1]; uint32_t mask = 1uL; // Define mask for temperature compensation bit 0 of lower byte of accelerometer bias registers uint8_t mask_bit[3] = {0, 0, 0}; // Define array to hold mask bit for each accelerometer bias axis for(ii = 0; ii < 3; ii++) { if(accel_bias_reg[ii] & mask) mask_bit[ii] = 0x01; // If temperature compensation bit is set, record that fact in mask_bit } // Construct total accelerometer bias, including calculated average accelerometer bias from above accel_bias_reg[0] -= (accel_bias[0]/8); // Subtract calculated averaged accelerometer bias scaled to 2048 LSB/g (16 g full scale) accel_bias_reg[1] -= (accel_bias[1]/8); accel_bias_reg[2] -= (accel_bias[2]/8); data[0] = (accel_bias_reg[0] >> 8) & 0xFF; data[1] = (accel_bias_reg[0]) & 0xFF; data[1] = data[1] | mask_bit[0]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[2] = (accel_bias_reg[1] >> 8) & 0xFF; data[3] = (accel_bias_reg[1]) & 0xFF; data[3] = data[3] | mask_bit[1]; // preserve temperature compensation bit when writing back to accelerometer bias registers data[4] = (accel_bias_reg[2] >> 8) & 0xFF; data[5] = (accel_bias_reg[2]) & 0xFF; data[5] = data[5] | mask_bit[2]; // preserve temperature compensation bit when writing back to accelerometer bias registers // Push accelerometer biases to hardware registers writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_XA_OFFS_H, data[0]); // might not be supported in MPU6050 writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_XA_OFFS_L_TC, data[1]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_YA_OFFS_H, data[2]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_YA_OFFS_L_TC, data[3]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ZA_OFFS_H, data[4]); writeByte(MPU6050_DEFAULT_ADDRESS, MPU6050_RA_ZA_OFFS_L_TC, data[5]); // Output scaled accelerometer biases for manual subtraction in the main program dest2[0] = (float)accel_bias[0]/(float)accelsensitivity; dest2[1] = (float)accel_bias[1]/(float)accelsensitivity; dest2[2] = (float)accel_bias[2]/(float)accelsensitivity; } uint8_t readByte(uint8_t address, uint8_t subAddress) { uint8_t data; // `data` will store the register data Wire.beginTransmission(address); // Initialize the Tx buffer Wire.write(subAddress); // Put slave register address in Tx buffer Wire.endTransmission(false); // Send the Tx buffer, but send a restart to keep connection alive Wire.requestFrom(address, (uint8_t) 1); // Read one byte from slave register address data = Wire.read(); // Fill Rx buffer with result return data; // Return data read from slave register } void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest) { Wire.beginTransmission(address); // Initialize the Tx buffer Wire.write(subAddress); // Put slave register address in Tx buffer Wire.endTransmission(false); // Send the Tx buffer, but send a restart to keep connection alive uint8_t i = 0; Wire.requestFrom(address, count); // Read bytes from slave register address while (Wire.available()) { dest[i++] = Wire.read(); } // Put read results in the Rx buffer }