Marco Mayer
/
Queue
Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
Diff: MPU9250.h
- Revision:
- 1:b36bbc1c6d27
- Parent:
- 0:6bf0743ece18
- Child:
- 2:c7897a3f5f11
--- a/MPU9250.h Sat Mar 28 15:28:19 2020 +0000
+++ b/MPU9250.h Sat Apr 11 08:15:48 2020 +0000
@@ -1,10 +1,10 @@
#ifndef MPU9250_H
#define MPU9250_H
-
+
#include "mbed.h"
#include "math.h"
-
-// See also MPU-9250 Register Map and Descriptions, Revision 4.0, RM-MPU-9250A-00, Rev. 1.4, 9/9/2013 for registers not listed in
+
+// See also MPU-9250 Register Map and Descriptions, Revision 4.0, RM-MPU-9250A-00, Rev. 1.4, 9/9/2013 for registers not listed in
// above document; the MPU9250 and MPU9150 are virtually identical but the latter has a different register map
//
//Magnetometer Registers
@@ -26,22 +26,13 @@
#define AK8963_ASAY 0x11 // Fuse ROM y-axis sensitivity adjustment value
#define AK8963_ASAZ 0x12 // Fuse ROM z-axis sensitivity adjustment value
-#define SELF_TEST_X_GYRO 0x00
-#define SELF_TEST_Y_GYRO 0x01
+#define SELF_TEST_X_GYRO 0x00
+#define SELF_TEST_Y_GYRO 0x01
#define SELF_TEST_Z_GYRO 0x02
-
-/*#define X_FINE_GAIN 0x03 // [7:0] fine gain
-#define Y_FINE_GAIN 0x04
-#define Z_FINE_GAIN 0x05
-#define XA_OFFSET_H 0x06 // User-defined trim values for accelerometer
-#define XA_OFFSET_L_TC 0x07
-#define YA_OFFSET_H 0x08
-#define YA_OFFSET_L_TC 0x09
-#define ZA_OFFSET_H 0x0A
-#define ZA_OFFSET_L_TC 0x0B */
+#define GRAVITATION 9.80665
#define SELF_TEST_X_ACCEL 0x0D
-#define SELF_TEST_Y_ACCEL 0x0E
+#define SELF_TEST_Y_ACCEL 0x0E
#define SELF_TEST_Z_ACCEL 0x0F
#define SELF_TEST_A 0x10
@@ -57,15 +48,15 @@
#define GYRO_CONFIG 0x1B
#define ACCEL_CONFIG 0x1C
#define ACCEL_CONFIG2 0x1D
-#define LP_ACCEL_ODR 0x1E
-#define WOM_THR 0x1F
+#define LP_ACCEL_ODR 0x1E
+#define WOM_THR 0x1F
#define MOT_DUR 0x20 // Duration counter threshold for motion interrupt generation, 1 kHz rate, LSB = 1 ms
#define ZMOT_THR 0x21 // Zero-motion detection threshold bits [7:0]
#define ZRMOT_DUR 0x22 // Duration counter threshold for zero motion interrupt generation, 16 Hz rate, LSB = 64 ms
#define FIFO_EN 0x23
-#define I2C_MST_CTRL 0x24
+#define I2C_MST_CTRL 0x24
#define I2C_SLV0_ADDR 0x25
#define I2C_SLV0_REG 0x26
#define I2C_SLV0_CTRL 0x27
@@ -141,7 +132,7 @@
#define DMP_RW_PNT 0x6E // Set read/write pointer to a specific start address in specified DMP bank
#define DMP_REG 0x6F // Register in DMP from which to read or to which to write
#define DMP_REG_1 0x70
-#define DMP_REG_2 0x71
+#define DMP_REG_2 0x71
#define FIFO_COUNTH 0x72
#define FIFO_COUNTL 0x73
#define FIFO_R_W 0x74
@@ -153,7 +144,7 @@
#define ZA_OFFSET_H 0x7D
#define ZA_OFFSET_L 0x7E
-// Using the MSENSR-9250 breakout board, ADO is set to 0
+// Using the MSENSR-9250 breakout board, ADO is set to 0
// Seven-bit device address is 110100 for ADO = 0 and 110101 for ADO = 1
//mbed uses the eight-bit device address, so shift seven-bit addresses left by one!
#define ADO 0
@@ -161,714 +152,84 @@
#define MPU9250_ADDRESS 0x69<<1 // Device address when ADO = 1
#else
#define MPU9250_ADDRESS 0x68<<1 // Device address when ADO = 0
-#endif
+#endif
+
// Set initial input parameters
enum Ascale {
- AFS_2G = 0,
- AFS_4G,
- AFS_8G,
- AFS_16G
+ AFS_2G = 0,
+ AFS_4G,
+ AFS_8G,
+ AFS_16G
};
enum Gscale {
- GFS_250DPS = 0,
- GFS_500DPS,
- GFS_1000DPS,
- GFS_2000DPS
+ GFS_250DPS = 0,
+ GFS_500DPS,
+ GFS_1000DPS,
+ GFS_2000DPS
};
enum Mscale {
- MFS_14BITS = 0, // 0.6 mG per LSB
- MFS_16BITS // 0.15 mG per LSB
+ MFS_14BITS = 0, // 0.6 mG per LSB
+ MFS_16BITS // 0.15 mG per LSB
};
-uint8_t Ascale = AFS_2G; // AFS_2G, AFS_4G, AFS_8G, AFS_16G
-uint8_t Gscale = GFS_250DPS; // GFS_250DPS, GFS_500DPS, GFS_1000DPS, GFS_2000DPS
-uint8_t Mscale = MFS_16BITS; // MFS_14BITS or MFS_16BITS, 14-bit or 16-bit magnetometer resolution
-uint8_t Mmode = 0x06; // Either 8 Hz 0x02) or 100 Hz (0x06) magnetometer data ODR
-float aRes, gRes, mRes; // scale resolutions per LSB for the sensors
-
-//Set up I2C, (SDA,SCL)
-I2C i2c(PB_9, PB_8);
-
-DigitalOut myled(LED1);
-
-// Pin definitions
-int intPin = 12; // These can be changed, 2 and 3 are the Arduinos ext int pins
-
-int16_t accelCount[3]; // Stores the 16-bit signed accelerometer sensor output
-int16_t gyroCount[3]; // Stores the 16-bit signed gyro sensor output
-int16_t magCount[3]; // Stores the 16-bit signed magnetometer sensor output
-float magCalibration[3] = {0, 0, 0}, magbias[3] = {0, 0, 0}; // Factory mag calibration and mag bias
-float gyroBias[3] = {0, 0, 0}, accelBias[3] = {0, 0, 0}; // Bias corrections for gyro and accelerometer
-float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
-int16_t tempCount; // Stores the real internal chip temperature in degrees Celsius
-float temperature;
-float SelfTest[6];
-
-int delt_t = 0; // used to control display output rate
-int _count = 0; // used to control display output rate
-
-// parameters for 6 DoF sensor fusion calculations
-float PI = 3.14159265358979323846f;
-float GyroMeasError = PI * (60.0f / 180.0f); // gyroscope measurement error in rads/s (start at 60 deg/s), then reduce after ~10 s to 3
-float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta
-float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s)
-float zeta = sqrt(3.0f / 4.0f) * GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value
-#define Kp 2.0f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral
-#define Ki 0.0f
-
-float pitch, yaw, roll;
-float deltat = 0.0f; // integration interval for both filter schemes
-int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval // used to calculate integration interval
-float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion
-float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method
-
-class MPU9250 {
-
- protected:
-
- public:
- //===================================================================================================================
-//====== Set of useful function to access acceleratio, gyroscope, and temperature data
-//===================================================================================================================
-
- void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
-{
- char data_write[2];
- data_write[0] = subAddress;
- data_write[1] = data;
- i2c.write(address, data_write, 2, 0);
-}
-
- char readByte(uint8_t address, uint8_t subAddress)
-{
- char data[1]; // `data` will store the register data
- char data_write[1];
- data_write[0] = subAddress;
- i2c.write(address, data_write, 1, 1); // no stop
- i2c.read(address, data, 1, 0);
- return data[0];
-}
-
- void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
-{
- char data[14];
- char data_write[1];
- data_write[0] = subAddress;
- i2c.write(address, data_write, 1, 1); // no stop
- i2c.read(address, data, count, 0);
- for(int ii = 0; ii < count; ii++) {
- dest[ii] = data[ii];
- }
-}
-
-
-void getMres() {
- switch (Mscale)
- {
- // Possible magnetometer scales (and their register bit settings) are:
- // 14 bit resolution (0) and 16 bit resolution (1)
- case MFS_14BITS:
- mRes = 10.0*4219.0/8190.0; // Proper scale to return milliGauss
- break;
- case MFS_16BITS:
- mRes = 10.0*4219.0/32760.0; // Proper scale to return milliGauss
- break;
- }
-}
+typedef struct {
+ float ax;
+ float ay;
+ float az;
+}accData_t;
-void getGres() {
- switch (Gscale)
- {
- // Possible gyro scales (and their register bit settings) are:
- // 250 DPS (00), 500 DPS (01), 1000 DPS (10), and 2000 DPS (11).
- // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
- case GFS_250DPS:
- gRes = 250.0/32768.0;
- break;
- case GFS_500DPS:
- gRes = 500.0/32768.0;
- break;
- case GFS_1000DPS:
- gRes = 1000.0/32768.0;
- break;
- case GFS_2000DPS:
- gRes = 2000.0/32768.0;
- break;
- }
-}
-
-
-void getAres() {
- switch (Ascale)
- {
- // Possible accelerometer scales (and their register bit settings) are:
- // 2 Gs (00), 4 Gs (01), 8 Gs (10), and 16 Gs (11).
- // Here's a bit of an algorith to calculate DPS/(ADC tick) based on that 2-bit value:
- case AFS_2G:
- aRes = 2.0/32768.0;
- break;
- case AFS_4G:
- aRes = 4.0/32768.0;
- break;
- case AFS_8G:
- aRes = 8.0/32768.0;
- break;
- case AFS_16G:
- aRes = 16.0/32768.0;
- break;
- }
-}
-
-
-void readAccelData(int16_t * destination)
-{
- uint8_t rawData[6]; // x/y/z accel register data stored here
- readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
- destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
- destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
- destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
-}
-
-void readGyroData(int16_t * destination)
-{
- uint8_t rawData[6]; // x/y/z gyro register data stored here
- readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
- destination[0] = (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
- destination[1] = (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
- destination[2] = (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
-}
-
-void readMagData(int16_t * destination)
-{
- uint8_t rawData[7]; // x/y/z gyro register data, ST2 register stored here, must read ST2 at end of data acquisition
- if(readByte(AK8963_ADDRESS, AK8963_ST1) & 0x01) { // wait for magnetometer data ready bit to be set
- readBytes(AK8963_ADDRESS, AK8963_XOUT_L, 7, &rawData[0]); // Read the six raw data and ST2 registers sequentially into data array
- uint8_t c = rawData[6]; // End data read by reading ST2 register
- if(!(c & 0x08)) { // Check if magnetic sensor overflow set, if not then report data
- destination[0] = (int16_t)(((int16_t)rawData[1] << 8) | rawData[0]); // Turn the MSB and LSB into a signed 16-bit value
- destination[1] = (int16_t)(((int16_t)rawData[3] << 8) | rawData[2]) ; // Data stored as little Endian
- destination[2] = (int16_t)(((int16_t)rawData[5] << 8) | rawData[4]) ;
- }
- }
-}
-
-int16_t readTempData()
-{
- uint8_t rawData[2]; // x/y/z gyro register data stored here
- readBytes(MPU9250_ADDRESS, TEMP_OUT_H, 2, &rawData[0]); // Read the two raw data registers sequentially into data array
- return (int16_t)(((int16_t)rawData[0]) << 8 | rawData[1]) ; // Turn the MSB and LSB into a 16-bit value
-}
-
-
-void resetMPU9250() {
- // reset device
- writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
- wait(0.1);
- }
-
- void initAK8963(float * destination)
-{
- // First extract the factory calibration for each magnetometer axis
- uint8_t rawData[3]; // x/y/z gyro calibration data stored here
- writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
- wait(0.01);
- writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x0F); // Enter Fuse ROM access mode
- wait(0.01);
- readBytes(AK8963_ADDRESS, AK8963_ASAX, 3, &rawData[0]); // Read the x-, y-, and z-axis calibration values
- destination[0] = (float)(rawData[0] - 128)/256.0f + 1.0f; // Return x-axis sensitivity adjustment values, etc.
- destination[1] = (float)(rawData[1] - 128)/256.0f + 1.0f;
- destination[2] = (float)(rawData[2] - 128)/256.0f + 1.0f;
- writeByte(AK8963_ADDRESS, AK8963_CNTL, 0x00); // Power down magnetometer
- wait(0.01);
- // Configure the magnetometer for continuous read and highest resolution
- // set Mscale bit 4 to 1 (0) to enable 16 (14) bit resolution in CNTL register,
- // and enable continuous mode data acquisition Mmode (bits [3:0]), 0010 for 8 Hz and 0110 for 100 Hz sample rates
- writeByte(AK8963_ADDRESS, AK8963_CNTL, Mscale << 4 | Mmode); // Set magnetometer data resolution and sample ODR
- wait(0.01);
-}
+class MPU9250 {
-void initMPU9250()
-{
- // Initialize MPU9250 device
- // wake up device
- writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Clear sleep mode bit (6), enable all sensors
- wait(0.1); // Delay 100 ms for PLL to get established on x-axis gyro; should check for PLL ready interrupt
-
- // get stable time source
- writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01); // Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
+public:
+ //------------------------------------------------------------------------------
+ // Function prototypes
- // Configure Gyro and Accelerometer
- // Disable FSYNC and set accelerometer and gyro bandwidth to 44 and 42 Hz, respectively;
- // DLPF_CFG = bits 2:0 = 010; this sets the sample rate at 1 kHz for both
- // Maximum delay is 4.9 ms which is just over a 200 Hz maximum rate
- writeByte(MPU9250_ADDRESS, CONFIG, 0x03);
-
- // Set sample rate = gyroscope output rate/(1 + SMPLRT_DIV)
- writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x04); // Use a 200 Hz rate; the same rate set in CONFIG above
-
- // Set gyroscope full scale range
- // Range selects FS_SEL and AFS_SEL are 0 - 3, so 2-bit values are left-shifted into positions 4:3
- uint8_t c = readByte(MPU9250_ADDRESS, GYRO_CONFIG);
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, c | Gscale << 3); // Set full scale range for the gyro
-
- // Set accelerometer configuration
- c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG);
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0xE0); // Clear self-test bits [7:5]
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c & ~0x18); // Clear AFS bits [4:3]
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, c | Ascale << 3); // Set full scale range for the accelerometer
-
- // Set accelerometer sample rate configuration
- // It is possible to get a 4 kHz sample rate from the accelerometer by choosing 1 for
- // accel_fchoice_b bit [3]; in this case the bandwidth is 1.13 kHz
- c = readByte(MPU9250_ADDRESS, ACCEL_CONFIG2);
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c & ~0x0F); // Clear accel_fchoice_b (bit 3) and A_DLPFG (bits [2:0])
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, c | 0x03); // Set accelerometer rate to 1 kHz and bandwidth to 41 Hz
-
- // The accelerometer, gyro, and thermometer are set to 1 kHz sample rates,
- // but all these rates are further reduced by a factor of 5 to 200 Hz because of the SMPLRT_DIV setting
+ void writeByte(uint8_t address, uint8_t subAddress, uint8_t data);
- // Configure Interrupts and Bypass Enable
- // Set interrupt pin active high, push-pull, and clear on read of INT_STATUS, enable I2C_BYPASS_EN so additional chips
- // can join the I2C bus and all can be controlled by the Arduino as master
- writeByte(MPU9250_ADDRESS, INT_PIN_CFG, 0x22);
- writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x01); // Enable data ready (bit 0) interrupt
-}
+ char readByte(uint8_t address, uint8_t subAddress);
-// 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 calibrateMPU9250(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(MPU9250_ADDRESS, PWR_MGMT_1, 0x80); // Write a one to bit 7 reset bit; toggle reset device
- wait(0.1);
-
-// get stable time source
-// Set clock source to be PLL with x-axis gyroscope reference, bits 2:0 = 001
- writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x01);
- writeByte(MPU9250_ADDRESS, PWR_MGMT_2, 0x00);
- wait(0.2);
-
-// Configure device for bias calculation
- writeByte(MPU9250_ADDRESS, INT_ENABLE, 0x00); // Disable all interrupts
- writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable FIFO
- writeByte(MPU9250_ADDRESS, PWR_MGMT_1, 0x00); // Turn on internal clock source
- writeByte(MPU9250_ADDRESS, I2C_MST_CTRL, 0x00); // Disable I2C master
- writeByte(MPU9250_ADDRESS, USER_CTRL, 0x00); // Disable FIFO and I2C master modes
- writeByte(MPU9250_ADDRESS, USER_CTRL, 0x0C); // Reset FIFO and DMP
- wait(0.015);
-
-// Configure MPU9250 gyro and accelerometer for bias calculation
- writeByte(MPU9250_ADDRESS, CONFIG, 0x01); // Set low-pass filter to 188 Hz
- writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set sample rate to 1 kHz
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00); // Set gyro full-scale to 250 degrees per second, maximum sensitivity
- writeByte(MPU9250_ADDRESS, 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
+ void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest);
-// Configure FIFO to capture accelerometer and gyro data for bias calculation
- writeByte(MPU9250_ADDRESS, USER_CTRL, 0x40); // Enable FIFO
- writeByte(MPU9250_ADDRESS, FIFO_EN, 0x78); // Enable gyro and accelerometer sensors for FIFO (max size 512 bytes in MPU-9250)
- wait(0.04); // accumulate 40 samples in 80 milliseconds = 480 bytes
-
-// At end of sample accumulation, turn off FIFO sensor read
- writeByte(MPU9250_ADDRESS, FIFO_EN, 0x00); // Disable gyro and accelerometer sensors for FIFO
- readBytes(MPU9250_ADDRESS, 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
+ void getMres();
- for (ii = 0; ii < packet_count; ii++) {
- int16_t accel_temp[3] = {0, 0, 0}, gyro_temp[3] = {0, 0, 0};
- readBytes(MPU9250_ADDRESS, 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;
+ void getGres();
-/// Push gyro biases to hardware registers
-/* writeByte(MPU9250_ADDRESS, XG_OFFSET_H, data[0]);
- writeByte(MPU9250_ADDRESS, XG_OFFSET_L, data[1]);
- writeByte(MPU9250_ADDRESS, YG_OFFSET_H, data[2]);
- writeByte(MPU9250_ADDRESS, YG_OFFSET_L, data[3]);
- writeByte(MPU9250_ADDRESS, ZG_OFFSET_H, data[4]);
- writeByte(MPU9250_ADDRESS, ZG_OFFSET_L, 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;
+ void getAres();
-// 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(MPU9250_ADDRESS, XA_OFFSET_H, 2, &data[0]); // Read factory accelerometer trim values
- accel_bias_reg[0] = (int16_t) ((int16_t)data[0] << 8) | data[1];
- readBytes(MPU9250_ADDRESS, YA_OFFSET_H, 2, &data[0]);
- accel_bias_reg[1] = (int16_t) ((int16_t)data[0] << 8) | data[1];
- readBytes(MPU9250_ADDRESS, ZA_OFFSET_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
- }
+ void readAccelData(int16_t * destination);
- // 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
-
-// Apparently this is not working for the acceleration biases in the MPU-9250
-// Are we handling the temperature correction bit properly?
-// Push accelerometer biases to hardware registers
-/* writeByte(MPU9250_ADDRESS, XA_OFFSET_H, data[0]);
- writeByte(MPU9250_ADDRESS, XA_OFFSET_L, data[1]);
- writeByte(MPU9250_ADDRESS, YA_OFFSET_H, data[2]);
- writeByte(MPU9250_ADDRESS, YA_OFFSET_L, data[3]);
- writeByte(MPU9250_ADDRESS, ZA_OFFSET_H, data[4]);
- writeByte(MPU9250_ADDRESS, ZA_OFFSET_L, 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;
-}
-
+ void readGyroData(int16_t * destination);
-// Accelerometer and gyroscope self test; check calibration wrt factory settings
-void MPU9250SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
-{
- uint8_t rawData[6] = {0, 0, 0, 0, 0, 0};
- uint8_t selfTest[6];
- int16_t gAvg[3], aAvg[3], aSTAvg[3], gSTAvg[3];
- float factoryTrim[6];
- uint8_t FS = 0;
-
- writeByte(MPU9250_ADDRESS, SMPLRT_DIV, 0x00); // Set gyro sample rate to 1 kHz
- writeByte(MPU9250_ADDRESS, CONFIG, 0x02); // Set gyro sample rate to 1 kHz and DLPF to 92 Hz
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 1<<FS); // Set full scale range for the gyro to 250 dps
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG2, 0x02); // Set accelerometer rate to 1 kHz and bandwidth to 92 Hz
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 1<<FS); // Set full scale range for the accelerometer to 2 g
+ void readMagData(int16_t * destination);
- for( int ii = 0; ii < 200; ii++) { // get average current values of gyro and acclerometer
-
- readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
- aAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
- aAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
- aAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
-
- readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
- gAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
- gAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
- gAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
- }
-
- for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average current readings
- aAvg[ii] /= 200;
- gAvg[ii] /= 200;
- }
-
-// Configure the accelerometer for self-test
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0xE0); // Enable self test on all three axes and set accelerometer range to +/- 2 g
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0xE0); // Enable self test on all three axes and set gyro range to +/- 250 degrees/s
- wait(0.025); // Delay a while to let the device stabilize
+ int16_t readTempData();
- for( int ii = 0; ii < 200; ii++) { // get average self-test values of gyro and acclerometer
-
- readBytes(MPU9250_ADDRESS, ACCEL_XOUT_H, 6, &rawData[0]); // Read the six raw data registers into data array
- aSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
- aSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
- aSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
-
- readBytes(MPU9250_ADDRESS, GYRO_XOUT_H, 6, &rawData[0]); // Read the six raw data registers sequentially into data array
- gSTAvg[0] += (int16_t)(((int16_t)rawData[0] << 8) | rawData[1]) ; // Turn the MSB and LSB into a signed 16-bit value
- gSTAvg[1] += (int16_t)(((int16_t)rawData[2] << 8) | rawData[3]) ;
- gSTAvg[2] += (int16_t)(((int16_t)rawData[4] << 8) | rawData[5]) ;
- }
-
- for (int ii =0; ii < 3; ii++) { // Get average of 200 values and store as average self-test readings
- aSTAvg[ii] /= 200;
- gSTAvg[ii] /= 200;
- }
-
- // Configure the gyro and accelerometer for normal operation
- writeByte(MPU9250_ADDRESS, ACCEL_CONFIG, 0x00);
- writeByte(MPU9250_ADDRESS, GYRO_CONFIG, 0x00);
- wait(0.025); // Delay a while to let the device stabilize
-
- // Retrieve accelerometer and gyro factory Self-Test Code from USR_Reg
- selfTest[0] = readByte(MPU9250_ADDRESS, SELF_TEST_X_ACCEL); // X-axis accel self-test results
- selfTest[1] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_ACCEL); // Y-axis accel self-test results
- selfTest[2] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_ACCEL); // Z-axis accel self-test results
- selfTest[3] = readByte(MPU9250_ADDRESS, SELF_TEST_X_GYRO); // X-axis gyro self-test results
- selfTest[4] = readByte(MPU9250_ADDRESS, SELF_TEST_Y_GYRO); // Y-axis gyro self-test results
- selfTest[5] = readByte(MPU9250_ADDRESS, SELF_TEST_Z_GYRO); // Z-axis gyro self-test results
+ void resetMPU9250();
- // Retrieve factory self-test value from self-test code reads
- factoryTrim[0] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[0] - 1.0) )); // FT[Xa] factory trim calculation
- factoryTrim[1] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[1] - 1.0) )); // FT[Ya] factory trim calculation
- factoryTrim[2] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[2] - 1.0) )); // FT[Za] factory trim calculation
- factoryTrim[3] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[3] - 1.0) )); // FT[Xg] factory trim calculation
- factoryTrim[4] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[4] - 1.0) )); // FT[Yg] factory trim calculation
- factoryTrim[5] = (float)(2620/1<<FS)*(pow( 1.01 , ((float)selfTest[5] - 1.0) )); // FT[Zg] factory trim calculation
-
- // Report results as a ratio of (STR - FT)/FT; the change from Factory Trim of the Self-Test Response
- // To get percent, must multiply by 100
- for (int i = 0; i < 3; i++) {
- destination[i] = 100.0*((float)(aSTAvg[i] - aAvg[i]))/factoryTrim[i]; // Report percent differences
- destination[i+3] = 100.0*((float)(gSTAvg[i] - gAvg[i]))/factoryTrim[i+3]; // Report percent differences
- }
-
-}
+ void initAK8963(float * destination);
-
+ void initMPU9250();
-// Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
-// (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
-// which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
-// device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
-// The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
-// but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
- void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
- {
- float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
- float norm;
- float hx, hy, _2bx, _2bz;
- float s1, s2, s3, s4;
- float qDot1, qDot2, qDot3, qDot4;
+ void calibrateMPU9250(float * dest1, float * dest2);
- // Auxiliary variables to avoid repeated arithmetic
- float _2q1mx;
- float _2q1my;
- float _2q1mz;
- float _2q2mx;
- float _4bx;
- float _4bz;
- float _2q1 = 2.0f * q1;
- float _2q2 = 2.0f * q2;
- float _2q3 = 2.0f * q3;
- float _2q4 = 2.0f * q4;
- float _2q1q3 = 2.0f * q1 * q3;
- float _2q3q4 = 2.0f * q3 * q4;
- float q1q1 = q1 * q1;
- float q1q2 = q1 * q2;
- float q1q3 = q1 * q3;
- float q1q4 = q1 * q4;
- float q2q2 = q2 * q2;
- float q2q3 = q2 * q3;
- float q2q4 = q2 * q4;
- float q3q3 = q3 * q3;
- float q3q4 = q3 * q4;
- float q4q4 = q4 * q4;
+ void MPU9250SelfTest(float * destination);
- // Normalise accelerometer measurement
- norm = sqrt(ax * ax + ay * ay + az * az);
- if (norm == 0.0f) return; // handle NaN
- norm = 1.0f/norm;
- ax *= norm;
- ay *= norm;
- az *= norm;
-
- // Normalise magnetometer measurement
- norm = sqrt(mx * mx + my * my + mz * mz);
- if (norm == 0.0f) return; // handle NaN
- norm = 1.0f/norm;
- mx *= norm;
- my *= norm;
- mz *= norm;
-
- // Reference direction of Earth's magnetic field
- _2q1mx = 2.0f * q1 * mx;
- _2q1my = 2.0f * q1 * my;
- _2q1mz = 2.0f * q1 * mz;
- _2q2mx = 2.0f * q2 * mx;
- hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
- hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
- _2bx = sqrt(hx * hx + hy * hy);
- _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
- _4bx = 2.0f * _2bx;
- _4bz = 2.0f * _2bz;
+ void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz);
- // Gradient decent algorithm corrective step
- s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
- s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
- s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
- s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
- norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude
- norm = 1.0f/norm;
- s1 *= norm;
- s2 *= norm;
- s3 *= norm;
- s4 *= norm;
-
- // Compute rate of change of quaternion
- qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
- qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
- qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
- qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
-
- // Integrate to yield quaternion
- q1 += qDot1 * deltat;
- q2 += qDot2 * deltat;
- q3 += qDot3 * deltat;
- q4 += qDot4 * deltat;
- norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion
- norm = 1.0f/norm;
- q[0] = q1 * norm;
- q[1] = q2 * norm;
- q[2] = q3 * norm;
- q[3] = q4 * norm;
-
- }
-
-
-
- // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
- // measured ones.
- void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
- {
- float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability
- float norm;
- float hx, hy, bx, bz;
- float vx, vy, vz, wx, wy, wz;
- float ex, ey, ez;
- float pa, pb, pc;
-
- // Auxiliary variables to avoid repeated arithmetic
- float q1q1 = q1 * q1;
- float q1q2 = q1 * q2;
- float q1q3 = q1 * q3;
- float q1q4 = q1 * q4;
- float q2q2 = q2 * q2;
- float q2q3 = q2 * q3;
- float q2q4 = q2 * q4;
- float q3q3 = q3 * q3;
- float q3q4 = q3 * q4;
- float q4q4 = q4 * q4;
-
- // Normalise accelerometer measurement
- norm = sqrt(ax * ax + ay * ay + az * az);
- if (norm == 0.0f) return; // handle NaN
- norm = 1.0f / norm; // use reciprocal for division
- ax *= norm;
- ay *= norm;
- az *= norm;
+ void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz);
- // Normalise magnetometer measurement
- norm = sqrt(mx * mx + my * my + mz * mz);
- if (norm == 0.0f) return; // handle NaN
- norm = 1.0f / norm; // use reciprocal for division
- mx *= norm;
- my *= norm;
- mz *= norm;
-
- // Reference direction of Earth's magnetic field
- hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
- hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
- bx = sqrt((hx * hx) + (hy * hy));
- bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
-
- // Estimated direction of gravity and magnetic field
- vx = 2.0f * (q2q4 - q1q3);
- vy = 2.0f * (q1q2 + q3q4);
- vz = q1q1 - q2q2 - q3q3 + q4q4;
- wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
- wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
- wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
+ void velocityUpdate(float ax, float ay, float az);
+
+ void readIMU();
+
+ void imuSetup();
+
+ accData_t getVelocityFromIMU();
+};
- // Error is cross product between estimated direction and measured direction of gravity
- ex = (ay * vz - az * vy) + (my * wz - mz * wy);
- ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
- ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
- if (Ki > 0.0f)
- {
- eInt[0] += ex; // accumulate integral error
- eInt[1] += ey;
- eInt[2] += ez;
- }
- else
- {
- eInt[0] = 0.0f; // prevent integral wind up
- eInt[1] = 0.0f;
- eInt[2] = 0.0f;
- }
-
- // Apply feedback terms
- gx = gx + Kp * ex + Ki * eInt[0];
- gy = gy + Kp * ey + Ki * eInt[1];
- gz = gz + Kp * ez + Ki * eInt[2];
-
- // Integrate rate of change of quaternion
- pa = q2;
- pb = q3;
- pc = q4;
- q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
- q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
- q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
- q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
-
- // Normalise quaternion
- norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
- norm = 1.0f / norm;
- q[0] = q1 * norm;
- q[1] = q2 * norm;
- q[2] = q3 * norm;
- q[3] = q4 * norm;
-
- }
- };
#endif
\ No newline at end of file