tom dunigan
MPU9250 test with polling or ISR
Diff: main.cpp
- Revision:
- 1:0158e4d78423
- Parent:
- 0:31cc139b7d1e
--- a/main.cpp Sat Sep 10 14:15:19 2016 +0000
+++ b/main.cpp Mon Nov 19 11:58:46 2018 +0000
@@ -1,17 +1,17 @@
/* MPU9250 Basic Example Code
by: Kris Winer
date: April 1, 2014
- license: Beerware - Use this code however you'd like. If you
+ license: Beerware - Use this code however you'd like. If you
find it useful you can buy me a beer some time.
-
- Demonstrate basic MPU-9250 functionality including parameterizing the register addresses, initializing the sensor,
- getting properly scaled accelerometer, gyroscope, and magnetometer data out. Added display functions to
- allow display to on breadboard monitor. Addition of 9 DoF sensor fusion using open source Madgwick and
+
+ Demonstrate basic MPU-9250 functionality including parameterizing the register addresses, initializing the sensor,
+ getting properly scaled accelerometer, gyroscope, and magnetometer data out. Added display functions to
+ allow display to on breadboard monitor. Addition of 9 DoF sensor fusion using open source Madgwick and
Mahony filter algorithms. Sketch runs on the 3.3 V 8 MHz Pro Mini and the Teensy 3.1.
-
+
SDA and SCL should have external pull-up resistors (to 3.3V).
10k resistors are on the EMSENSR-9250 breakout board.
-
+
Hardware setup:
MPU9250 Breakout --------- Arduino
VDD ---------------------- 3.3V
@@ -19,14 +19,14 @@
SDA ----------------------- A4
SCL ----------------------- A5
GND ---------------------- GND
-
- Note: The MPU9250 is an I2C sensor and uses the Arduino Wire library.
+
+ Note: The MPU9250 is an I2C sensor and uses the Arduino Wire library.
Because the sensor is not 5V tolerant, we are using a 3.3 V 8 MHz Pro Mini or a 3.3 V Teensy 3.1.
We have disabled the internal pull-ups used by the Wire library in the Wire.h/twi.c utility file.
We are also using the 400 kHz fast I2C mode by setting the TWI_FREQ to 400000L /twi.h utility file.
*/
-
-//#include "ST_F401_84MHZ.h"
+
+//#include "ST_F401_84MHZ.h"
//F401_init84 myinit(0);
#include "mbed.h"
#include "MPU9250.h"
@@ -35,70 +35,69 @@
float sum = 0;
uint32_t sumCount = 0;
- MPU9250 mpu9250;
-
- Timer t;
+MPU9250 mpu9250;
- Serial pc(USBTX, USBRX); // tx, rx
+Timer t;
+
+Serial pc(USBTX, USBRX); // tx, rx
volatile bool newData = false;
InterruptIn isrPin(D12); //k64 D12 dragon PD_0
-void mpuisr() {
+void mpuisr()
+{
newData=true;
}
-
+
int main()
{
- pc.baud(9600);
+ pc.baud(9600);
+
+ //Set up I2C
+ i2c.frequency(400000); // use fast (400 kHz) I2C
+
+ pc.printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);
+
+ t.start();
+ isrPin.rise(&mpuisr);
- //Set up I2C
- i2c.frequency(400000); // use fast (400 kHz) I2C
-
- pc.printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);
-
- t.start();
- isrPin.rise(&mpuisr);
-
- // Read the WHO_AM_I register, this is a good test of communication
- uint8_t whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
- pc.printf("I AM 0x%x\n\r", whoami); pc.printf("I SHOULD BE 0x71\n\r");
-
- if (whoami == 0x71) // WHO_AM_I should always be 0x68
- {
- pc.printf("MPU9250 is online...\n\r");
- wait(1);
+ // Read the WHO_AM_I register, this is a good test of communication
+ uint8_t whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
+ pc.printf("I AM 0x%x\n\r", whoami);
+ pc.printf("I SHOULD BE 0x71\n\r");
+
+ if (whoami == 0x71) { // WHO_AM_I should always be 0x68
+ pc.printf("MPU9250 is online...\n\r");
+ wait(1);
+
-
- mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
- mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
- pc.printf("x gyro bias = %f\n\r", gyroBias[0]);
- pc.printf("y gyro bias = %f\n\r", gyroBias[1]);
- pc.printf("z gyro bias = %f\n\r", gyroBias[2]);
- pc.printf("x accel bias = %f\n\r", accelBias[0]);
- pc.printf("y accel bias = %f\n\r", accelBias[1]);
- pc.printf("z accel bias = %f\n\r", accelBias[2]);
- wait(2);
- mpu9250.initMPU9250();
- pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
- mpu9250.initAK8963(magCalibration);
- pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
- pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale));
- pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale));
- if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r");
- if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r");
- if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r");
- if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r");
- wait(2);
- }
- else
- {
- pc.printf("Could not connect to MPU9250: \n\r");
- pc.printf("%#x \n", whoami);
+ mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
+ mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
+ pc.printf("x gyro bias = %f\n\r", gyroBias[0]);
+ pc.printf("y gyro bias = %f\n\r", gyroBias[1]);
+ pc.printf("z gyro bias = %f\n\r", gyroBias[2]);
+ pc.printf("x accel bias = %f\n\r", accelBias[0]);
+ pc.printf("y accel bias = %f\n\r", accelBias[1]);
+ pc.printf("z accel bias = %f\n\r", accelBias[2]);
+ wait(2);
+ mpu9250.initMPU9250();
+ pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
+ mpu9250.initAK8963(magCalibration);
+ pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
+ pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale));
+ pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale));
+ if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r");
+ if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r");
+ if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r");
+ if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r");
+ wait(2);
+ } else {
+ pc.printf("Could not connect to MPU9250: \n\r");
+ pc.printf("%#x \n", whoami);
-
- while(1) ; // Loop forever if communication doesn't happen
+
+ while(1) ; // Loop forever if communication doesn't happen
}
mpu9250.getAres(); // Get accelerometer sensitivity
@@ -111,109 +110,109 @@
magbias[1] = +120.; // User environmental x-axis correction in milliGauss
magbias[2] = +125.; // User environmental x-axis correction in milliGauss
- while(1) {
- static int readycnt=0;
- // If intPin goes high, all data registers have new data
-
+ while(1) {
+ static int readycnt=0;
+ // If intPin goes high, all data registers have new data
+
#if USE_ISR
- if(newData) {
- newData=false;
- mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS); //? need this with ISR
+ if(newData) {
+ newData=false;
+ mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS); //? need this with ISR
#else
- if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
+ if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
#endif
- readycnt++;
- mpu9250.readAccelData(accelCount); // Read the x/y/z adc values
- // Now we'll calculate the accleration value into actual g's
- ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
- ay = (float)accelCount[1]*aRes - accelBias[1];
- az = (float)accelCount[2]*aRes - accelBias[2];
-
- mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values
- // Calculate the gyro value into actual degrees per second
- gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
- gy = (float)gyroCount[1]*gRes - gyroBias[1];
- gz = (float)gyroCount[2]*gRes - gyroBias[2];
-
- mpu9250.readMagData(magCount); // Read the x/y/z adc values
- // Calculate the magnetometer values in milliGauss
- // Include factory calibration per data sheet and user environmental corrections
- mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; // get actual magnetometer value, this depends on scale being set
- my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1];
- mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2];
- }
-
- Now = t.read_us();
- deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
- lastUpdate = Now;
-
- sum += deltat;
- sumCount++;
-
+ readycnt++;
+ mpu9250.readAccelData(accelCount); // Read the x/y/z adc values
+ // Now we'll calculate the accleration value into actual g's
+ ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
+ ay = (float)accelCount[1]*aRes - accelBias[1];
+ az = (float)accelCount[2]*aRes - accelBias[2];
+
+ mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values
+ // Calculate the gyro value into actual degrees per second
+ gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
+ gy = (float)gyroCount[1]*gRes - gyroBias[1];
+ gz = (float)gyroCount[2]*gRes - gyroBias[2];
+
+ mpu9250.readMagData(magCount); // Read the x/y/z adc values
+ // Calculate the magnetometer values in milliGauss
+ // Include factory calibration per data sheet and user environmental corrections
+ mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; // get actual magnetometer value, this depends on scale being set
+ my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1];
+ mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2];
+ }
+
+ Now = t.read_us();
+ deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
+ lastUpdate = Now;
+
+ sum += deltat;
+ sumCount++;
+
// if(lastUpdate - firstUpdate > 10000000.0f) {
// beta = 0.04; // decrease filter gain after stabilized
// zeta = 0.015; // increasey bias drift gain after stabilized
- // }
-
- // Pass gyro rate as rad/s
- uint32_t us = t.read_us();
- mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
- us = t.read_us()-us;
- // mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
+// }
+
+ // Pass gyro rate as rad/s
+ uint32_t us = t.read_us();
+ mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
+ us = t.read_us()-us;
+// mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
- // Serial print and/or display at 0.5 s rate independent of data rates
- delt_t = t.read_ms() - count;
- if (delt_t > 500) { // update LCD once per half-second independent of read rate
- pc.printf("readycnt %d us %d\n",readycnt,us);
- readycnt=0;
- pc.printf("ax = %f", 1000*ax);
- pc.printf(" ay = %f", 1000*ay);
- pc.printf(" az = %f mg\n\r", 1000*az);
+ // Serial print and/or display at 0.5 s rate independent of data rates
+ delt_t = t.read_ms() - count;
+ if (delt_t > 500) { // update LCD once per half-second independent of read rate
+ pc.printf("readycnt %d us %d\n",readycnt,us);
+ readycnt=0;
+ pc.printf("ax = %f", 1000*ax);
+ pc.printf(" ay = %f", 1000*ay);
+ pc.printf(" az = %f mg\n\r", 1000*az);
+
+ pc.printf("gx = %f", gx);
+ pc.printf(" gy = %f", gy);
+ pc.printf(" gz = %f deg/s\n\r", gz);
+
+ pc.printf("gx = %f", mx);
+ pc.printf(" gy = %f", my);
+ pc.printf(" gz = %f mG\n\r", mz);
+
+ tempCount = mpu9250.readTempData(); // Read the adc values
+ temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade
+ pc.printf("temperature = %f C\n\r", temperature);
- pc.printf("gx = %f", gx);
- pc.printf(" gy = %f", gy);
- pc.printf(" gz = %f deg/s\n\r", gz);
-
- pc.printf("gx = %f", mx);
- pc.printf(" gy = %f", my);
- pc.printf(" gz = %f mG\n\r", mz);
-
- tempCount = mpu9250.readTempData(); // Read the adc values
- temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade
- pc.printf("temperature = %f C\n\r", temperature);
-
- pc.printf("q0 = %f\n\r", q[0]);
- pc.printf("q1 = %f\n\r", q[1]);
- pc.printf("q2 = %f\n\r", q[2]);
- pc.printf("q3 = %f\n\r", q[3]);
+ pc.printf("q0 = %f\n\r", q[0]);
+ pc.printf("q1 = %f\n\r", q[1]);
+ pc.printf("q2 = %f\n\r", q[2]);
+ pc.printf("q3 = %f\n\r", q[3]);
+
+
-
-
- // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
- // In this coordinate system, the positive z-axis is down toward Earth.
- // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise.
- // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
- // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
- // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
- // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be
- // applied in the correct order which for this configuration is yaw, pitch, and then roll.
- // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
- yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]);
- pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
- roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]);
- pitch *= 180.0f / PI;
- yaw *= 180.0f / PI;
- yaw -= 13.8f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04
- roll *= 180.0f / PI;
+ // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
+ // In this coordinate system, the positive z-axis is down toward Earth.
+ // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise.
+ // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
+ // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
+ // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
+ // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be
+ // applied in the correct order which for this configuration is yaw, pitch, and then roll.
+ // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
+ yaw = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]);
+ pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
+ roll = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]);
+ pitch *= 180.0f / PI;
+ yaw *= 180.0f / PI;
+ yaw -= 13.8f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04
+ roll *= 180.0f / PI;
- pc.printf("Yaw, Pitch, Roll: %f %f %f\n\r", yaw, pitch, roll);
- pc.printf("average rate = %f\n\r", (float) sumCount/sum);
-
- myled= !myled;
- count = t.read_ms();
- sum = 0;
- sumCount = 0;
-}
-}
-
- }
\ No newline at end of file
+ pc.printf("Yaw, Pitch, Roll: %f %f %f\n\r", yaw, pitch, roll);
+ pc.printf("average rate = %f\n\r", (float) sumCount/sum);
+
+ myled= !myled;
+ count = t.read_ms();
+ sum = 0;
+ sumCount = 0;
+ }
+ }
+
+}
\ No newline at end of file