Marco Mayer / Mbed OS Queue

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main.cpp@0:6bf0743ece18, 2020-03-28 (annotated)

Committer:
demayer
Date:
Sat Mar 28 15:28:19 2020 +0000
Revision:
0:6bf0743ece18
Child:
1:b36bbc1c6d27
IMU Thread with an event-queue running parallel to handle tasks like a 5 times blinking LED. Button with interrupt detected.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
demayer 0:6bf0743ece18 1 #include "mbed.h"
demayer 0:6bf0743ece18 2 #include "mbed_events.h"
demayer 0:6bf0743ece18 3 #include "MPU9250.h"
demayer 0:6bf0743ece18 4
demayer 0:6bf0743ece18 5 DigitalOut led1(LED1);
demayer 0:6bf0743ece18 6 InterruptIn sw(USER_BUTTON);
demayer 0:6bf0743ece18 7
demayer 0:6bf0743ece18 8 Thread eventthread;
demayer 0:6bf0743ece18 9 Thread imuthread;
demayer 0:6bf0743ece18 10 bool read_imu_isrunning;
demayer 0:6bf0743ece18 11
demayer 0:6bf0743ece18 12
demayer 0:6bf0743ece18 13 // Pin defines
demayer 0:6bf0743ece18 14 DigitalOut led_green(D4);
demayer 0:6bf0743ece18 15
demayer 0:6bf0743ece18 16 //-----------------------------------------------------
demayer 0:6bf0743ece18 17 //IMU
demayer 0:6bf0743ece18 18 float sum = 0;
demayer 0:6bf0743ece18 19 uint32_t sumCount = 0;
demayer 0:6bf0743ece18 20 char buffer[14];
demayer 0:6bf0743ece18 21
demayer 0:6bf0743ece18 22 MPU9250 mpu9250;
demayer 0:6bf0743ece18 23 Timer t;
demayer 0:6bf0743ece18 24 Serial pc(USBTX, USBRX); // tx, rx
demayer 0:6bf0743ece18 25 //-----------------------------------------------------
demayer 0:6bf0743ece18 26
demayer 0:6bf0743ece18 27 void rise_handler(void)
demayer 0:6bf0743ece18 28 {
demayer 0:6bf0743ece18 29 printf("rise_handler in context %p\r\n", Thread::gettid());
demayer 0:6bf0743ece18 30 // Toggle LED
demayer 0:6bf0743ece18 31 led1 = !led1;
demayer 0:6bf0743ece18 32 for (int i = 0; i<10; i++) {
demayer 0:6bf0743ece18 33 led_green = !led_green;
demayer 0:6bf0743ece18 34 wait(0.5);
demayer 0:6bf0743ece18 35 }
demayer 0:6bf0743ece18 36 }
demayer 0:6bf0743ece18 37
demayer 0:6bf0743ece18 38 void fall_handler(void)
demayer 0:6bf0743ece18 39 {
demayer 0:6bf0743ece18 40 printf("fall_handler in context %p\r\n", Thread::gettid());
demayer 0:6bf0743ece18 41 // Toggle LED
demayer 0:6bf0743ece18 42 led1 = !led1;
demayer 0:6bf0743ece18 43 }
demayer 0:6bf0743ece18 44
demayer 0:6bf0743ece18 45 void readIMU()
demayer 0:6bf0743ece18 46 {
demayer 0:6bf0743ece18 47 while(read_imu_isrunning) {
demayer 0:6bf0743ece18 48 pc.printf("in thread readIMU\n\r");
demayer 0:6bf0743ece18 49 // If intPin goes high, all data registers have new data
demayer 0:6bf0743ece18 50 if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
demayer 0:6bf0743ece18 51
demayer 0:6bf0743ece18 52 mpu9250.readAccelData(accelCount); // Read the x/y/z adc values
demayer 0:6bf0743ece18 53 // Now we'll calculate the accleration value into actual g's
demayer 0:6bf0743ece18 54 ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
demayer 0:6bf0743ece18 55 ay = (float)accelCount[1]*aRes - accelBias[1];
demayer 0:6bf0743ece18 56 az = (float)accelCount[2]*aRes - accelBias[2];
demayer 0:6bf0743ece18 57
demayer 0:6bf0743ece18 58 mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values
demayer 0:6bf0743ece18 59 // Calculate the gyro value into actual degrees per second
demayer 0:6bf0743ece18 60 gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
demayer 0:6bf0743ece18 61 gy = (float)gyroCount[1]*gRes - gyroBias[1];
demayer 0:6bf0743ece18 62 gz = (float)gyroCount[2]*gRes - gyroBias[2];
demayer 0:6bf0743ece18 63
demayer 0:6bf0743ece18 64 mpu9250.readMagData(magCount); // Read the x/y/z adc values
demayer 0:6bf0743ece18 65 // Calculate the magnetometer values in milliGauss
demayer 0:6bf0743ece18 66 // Include factory calibration per data sheet and user environmental corrections
demayer 0:6bf0743ece18 67 mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; // get actual magnetometer value, this depends on scale being set
demayer 0:6bf0743ece18 68 my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1];
demayer 0:6bf0743ece18 69 mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2];
demayer 0:6bf0743ece18 70 }
demayer 0:6bf0743ece18 71
demayer 0:6bf0743ece18 72 Now = t.read_us();
demayer 0:6bf0743ece18 73 deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
demayer 0:6bf0743ece18 74 lastUpdate = Now;
demayer 0:6bf0743ece18 75
demayer 0:6bf0743ece18 76 sum += deltat;
demayer 0:6bf0743ece18 77 sumCount++;
demayer 0:6bf0743ece18 78
demayer 0:6bf0743ece18 79 // if(lastUpdate - firstUpdate > 10000000.0f) {
demayer 0:6bf0743ece18 80 // beta = 0.04; // decrease filter gain after stabilized
demayer 0:6bf0743ece18 81 // zeta = 0.015; // increasey bias drift gain after stabilized
demayer 0:6bf0743ece18 82 // }
demayer 0:6bf0743ece18 83
demayer 0:6bf0743ece18 84 // Pass gyro rate as rad/s
demayer 0:6bf0743ece18 85 mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
demayer 0:6bf0743ece18 86 //mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
demayer 0:6bf0743ece18 87
demayer 0:6bf0743ece18 88 // Serial print and/or display at 0.5 s rate independent of data rates
demayer 0:6bf0743ece18 89 delt_t = t.read_ms() - _count;
demayer 0:6bf0743ece18 90 if (delt_t > 50) { // update LCD once per half-second independent of read rate
demayer 0:6bf0743ece18 91
demayer 0:6bf0743ece18 92 /*pc.printf("ax = %f", 1000*ax);
demayer 0:6bf0743ece18 93 pc.printf(" ay = %f", 1000*ay);
demayer 0:6bf0743ece18 94 pc.printf(" az = %f mg\n\r", 1000*az);
demayer 0:6bf0743ece18 95
demayer 0:6bf0743ece18 96 pc.printf("gx = %f", gx);
demayer 0:6bf0743ece18 97 pc.printf(" gy = %f", gy);
demayer 0:6bf0743ece18 98 pc.printf(" gz = %f deg/s\n\r", gz);
demayer 0:6bf0743ece18 99
demayer 0:6bf0743ece18 100 pc.printf("gx = %f", mx);
demayer 0:6bf0743ece18 101 pc.printf(" gy = %f", my);
demayer 0:6bf0743ece18 102 pc.printf(" gz = %f mG\n\r", mz);*/
demayer 0:6bf0743ece18 103
demayer 0:6bf0743ece18 104 tempCount = mpu9250.readTempData(); // Read the adc values
demayer 0:6bf0743ece18 105 temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade
demayer 0:6bf0743ece18 106 //pc.printf(" temperature = %f C\n\r", temperature);
demayer 0:6bf0743ece18 107
demayer 0:6bf0743ece18 108 /*pc.printf("q0 = %f\n\r", q[0]);
demayer 0:6bf0743ece18 109 pc.printf("q1 = %f\n\r", q[1]);
demayer 0:6bf0743ece18 110 pc.printf("q2 = %f\n\r", q[2]);
demayer 0:6bf0743ece18 111 pc.printf("q3 = %f\n\r", q[3]);*/
demayer 0:6bf0743ece18 112
demayer 0:6bf0743ece18 113 /* lcd.clear();
demayer 0:6bf0743ece18 114 lcd.printString("MPU9250", 0, 0);
demayer 0:6bf0743ece18 115 lcd.printString("x y z", 0, 1);
demayer 0:6bf0743ece18 116 sprintf(buffer, "%d %d %d mg", (int)(1000.0f*ax), (int)(1000.0f*ay), (int)(1000.0f*az));
demayer 0:6bf0743ece18 117 lcd.printString(buffer, 0, 2);
demayer 0:6bf0743ece18 118 sprintf(buffer, "%d %d %d deg/s", (int)gx, (int)gy, (int)gz);
demayer 0:6bf0743ece18 119 lcd.printString(buffer, 0, 3);
demayer 0:6bf0743ece18 120 sprintf(buffer, "%d %d %d mG", (int)mx, (int)my, (int)mz);
demayer 0:6bf0743ece18 121 lcd.printString(buffer, 0, 4);
demayer 0:6bf0743ece18 122 */
demayer 0:6bf0743ece18 123 // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
demayer 0:6bf0743ece18 124 // In this coordinate system, the positive z-axis is down toward Earth.
demayer 0:6bf0743ece18 125 // 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.
demayer 0:6bf0743ece18 126 // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
demayer 0:6bf0743ece18 127 // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
demayer 0:6bf0743ece18 128 // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
demayer 0:6bf0743ece18 129 // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be
demayer 0:6bf0743ece18 130 // applied in the correct order which for this configuration is yaw, pitch, and then roll.
demayer 0:6bf0743ece18 131 // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
demayer 0:6bf0743ece18 132 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]);
demayer 0:6bf0743ece18 133 pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
demayer 0:6bf0743ece18 134 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]);
demayer 0:6bf0743ece18 135 pitch *= 180.0f / PI;
demayer 0:6bf0743ece18 136 yaw *= 180.0f / PI;
demayer 0:6bf0743ece18 137 yaw -= 2.93f; // Declination at 8572 Berg TG: +2° 56'
demayer 0:6bf0743ece18 138 roll *= 180.0f / PI;
demayer 0:6bf0743ece18 139
demayer 0:6bf0743ece18 140 pc.printf("Yaw, Pitch, Roll: %f %f %f\n\r", yaw, pitch, roll);
demayer 0:6bf0743ece18 141 //pc.printf("average rate = %f\n\r", (float) sumCount/sum);
demayer 0:6bf0743ece18 142 // sprintf(buffer, "YPR: %f %f %f", yaw, pitch, roll);
demayer 0:6bf0743ece18 143 // lcd.printString(buffer, 0, 4);
demayer 0:6bf0743ece18 144 // sprintf(buffer, "rate = %f", (float) sumCount/sum);
demayer 0:6bf0743ece18 145 // lcd.printString(buffer, 0, 5);
demayer 0:6bf0743ece18 146
demayer 0:6bf0743ece18 147 myled= !myled;
demayer 0:6bf0743ece18 148 _count = t.read_ms();
demayer 0:6bf0743ece18 149
demayer 0:6bf0743ece18 150 if(_count > 1<<21) {
demayer 0:6bf0743ece18 151 t.start(); // start the timer over again if ~30 minutes has passed
demayer 0:6bf0743ece18 152 _count = 0;
demayer 0:6bf0743ece18 153 deltat= 0;
demayer 0:6bf0743ece18 154 lastUpdate = t.read_us();
demayer 0:6bf0743ece18 155 }
demayer 0:6bf0743ece18 156 sum = 0;
demayer 0:6bf0743ece18 157 sumCount = 0;
demayer 0:6bf0743ece18 158 }
demayer 0:6bf0743ece18 159 }
demayer 0:6bf0743ece18 160 }
demayer 0:6bf0743ece18 161
demayer 0:6bf0743ece18 162 void imuSetup()
demayer 0:6bf0743ece18 163 {
demayer 0:6bf0743ece18 164 read_imu_isrunning = true;
demayer 0:6bf0743ece18 165 //Set up I2C
demayer 0:6bf0743ece18 166 i2c.frequency(400000); // use fast (400 kHz) I2C
demayer 0:6bf0743ece18 167
demayer 0:6bf0743ece18 168 pc.printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);
demayer 0:6bf0743ece18 169
demayer 0:6bf0743ece18 170 t.start();
demayer 0:6bf0743ece18 171 // lcd.setBrightness(0.05);
demayer 0:6bf0743ece18 172
demayer 0:6bf0743ece18 173
demayer 0:6bf0743ece18 174 // Read the WHO_AM_I register, this is a good test of communication
demayer 0:6bf0743ece18 175 uint8_t whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
demayer 0:6bf0743ece18 176 pc.printf("I AM 0x%x\n\r", whoami);
demayer 0:6bf0743ece18 177 pc.printf("I SHOULD BE 0x71\n\r");
demayer 0:6bf0743ece18 178
demayer 0:6bf0743ece18 179 if (whoami == 0x71) { // WHO_AM_I should always be 0x68
demayer 0:6bf0743ece18 180 pc.printf("MPU9250 WHO_AM_I is 0x%x\n\r", whoami);
demayer 0:6bf0743ece18 181 pc.printf("MPU9250 is online...\n\r");
demayer 0:6bf0743ece18 182 sprintf(buffer, "0x%x", whoami);
demayer 0:6bf0743ece18 183 wait(1);
demayer 0:6bf0743ece18 184
demayer 0:6bf0743ece18 185 mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
demayer 0:6bf0743ece18 186 mpu9250.MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values
demayer 0:6bf0743ece18 187 pc.printf("x-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[0]);
demayer 0:6bf0743ece18 188 pc.printf("y-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[1]);
demayer 0:6bf0743ece18 189 pc.printf("z-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[2]);
demayer 0:6bf0743ece18 190 pc.printf("x-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[3]);
demayer 0:6bf0743ece18 191 pc.printf("y-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[4]);
demayer 0:6bf0743ece18 192 pc.printf("z-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[5]);
demayer 0:6bf0743ece18 193 mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
demayer 0:6bf0743ece18 194 pc.printf("x gyro bias = %f\n\r", gyroBias[0]);
demayer 0:6bf0743ece18 195 pc.printf("y gyro bias = %f\n\r", gyroBias[1]);
demayer 0:6bf0743ece18 196 pc.printf("z gyro bias = %f\n\r", gyroBias[2]);
demayer 0:6bf0743ece18 197 pc.printf("x accel bias = %f\n\r", accelBias[0]);
demayer 0:6bf0743ece18 198 pc.printf("y accel bias = %f\n\r", accelBias[1]);
demayer 0:6bf0743ece18 199 pc.printf("z accel bias = %f\n\r", accelBias[2]);
demayer 0:6bf0743ece18 200 wait(2);
demayer 0:6bf0743ece18 201 mpu9250.initMPU9250();
demayer 0:6bf0743ece18 202 pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
demayer 0:6bf0743ece18 203 mpu9250.initAK8963(magCalibration);
demayer 0:6bf0743ece18 204 pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
demayer 0:6bf0743ece18 205 pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale));
demayer 0:6bf0743ece18 206 pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale));
demayer 0:6bf0743ece18 207 if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r");
demayer 0:6bf0743ece18 208 if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r");
demayer 0:6bf0743ece18 209 if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r");
demayer 0:6bf0743ece18 210 if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r");
demayer 0:6bf0743ece18 211 wait(1);
demayer 0:6bf0743ece18 212 } else {
demayer 0:6bf0743ece18 213 pc.printf("Could not connect to MPU9250: \n\r");
demayer 0:6bf0743ece18 214 pc.printf("%#x \n", whoami);
demayer 0:6bf0743ece18 215 sprintf(buffer, "WHO_AM_I 0x%x", whoami);
demayer 0:6bf0743ece18 216
demayer 0:6bf0743ece18 217 while(1) {
demayer 0:6bf0743ece18 218 // Loop forever if communication doesn't happen
demayer 0:6bf0743ece18 219 pc.printf("commication not happening\n\r");
demayer 0:6bf0743ece18 220 }
demayer 0:6bf0743ece18 221 }
demayer 0:6bf0743ece18 222
demayer 0:6bf0743ece18 223 mpu9250.getAres(); // Get accelerometer sensitivity
demayer 0:6bf0743ece18 224 mpu9250.getGres(); // Get gyro sensitivity
demayer 0:6bf0743ece18 225 mpu9250.getMres(); // Get magnetometer sensitivity
demayer 0:6bf0743ece18 226 pc.printf("Accelerometer sensitivity is %f LSB/g \n\r", 1.0f/aRes);
demayer 0:6bf0743ece18 227 pc.printf("Gyroscope sensitivity is %f LSB/deg/s \n\r", 1.0f/gRes);
demayer 0:6bf0743ece18 228 pc.printf("Magnetometer sensitivity is %f LSB/G \n\r", 1.0f/mRes);
demayer 0:6bf0743ece18 229 magbias[0] = +470.; // User environmental x-axis correction in milliGauss, should be automatically calculated
demayer 0:6bf0743ece18 230 magbias[1] = +120.; // User environmental x-axis correction in milliGauss
demayer 0:6bf0743ece18 231 magbias[2] = +125.; // User environmental x-axis correction in milliGauss
demayer 0:6bf0743ece18 232 }
demayer 0:6bf0743ece18 233
demayer 0:6bf0743ece18 234
demayer 0:6bf0743ece18 235 int main()
demayer 0:6bf0743ece18 236 {
demayer 0:6bf0743ece18 237 pc.baud(9600);
demayer 0:6bf0743ece18 238 imuSetup();
demayer 0:6bf0743ece18 239 imuthread.start(readIMU);
demayer 0:6bf0743ece18 240
demayer 0:6bf0743ece18 241 // Request the shared queue
demayer 0:6bf0743ece18 242 EventQueue *queue = mbed_event_queue();
demayer 0:6bf0743ece18 243 printf("Starting in context %p\r\n", Thread::gettid());
demayer 0:6bf0743ece18 244
demayer 0:6bf0743ece18 245 // The 'rise' handler will execute in IRQ context
demayer 0:6bf0743ece18 246 sw.rise(queue->event(rise_handler));
demayer 0:6bf0743ece18 247 // The 'fall' handler will execute in the context of the shared queue (actually the main thread)
demayer 0:6bf0743ece18 248 sw.fall(queue->event(fall_handler));
demayer 0:6bf0743ece18 249 // Setup complete, so we now dispatch the shared queue from main
demayer 0:6bf0743ece18 250 queue->dispatch_forever();
demayer 0:6bf0743ece18 251 }