Project Football / Mbed 2 deprecated MPU9250IOT

Veloc

Dependencies:   mbed

main.cpp@0:3af3f05e8f7d, 2018-11-02 (annotated)

Committer:
kong4580
Date:
Fri Nov 02 05:58:27 2018 +0000
Revision:
0:3af3f05e8f7d
Child:
1:44a18ed16bae
Mannual Calibate Press button before upload code

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kong4580 0:3af3f05e8f7d 1 /* MPU9250 Basic Example Code
kong4580 0:3af3f05e8f7d 2 by: Kris Winer
kong4580 0:3af3f05e8f7d 3 date: April 1, 2014
kong4580 0:3af3f05e8f7d 4 license: Beerware - Use this code however you'd like. If you
kong4580 0:3af3f05e8f7d 5 find it useful you can buy me a beer some time.
kong4580 0:3af3f05e8f7d 6
kong4580 0:3af3f05e8f7d 7 Demonstrate basic MPU-9250 functionality including parameterizing the register addresses, initializing the sensor,
kong4580 0:3af3f05e8f7d 8 getting properly scaled accelerometer, gyroscope, and magnetometer data out. Added display functions to
kong4580 0:3af3f05e8f7d 9 allow display to on breadboard monitor. Addition of 9 DoF sensor fusion using open source Madgwick and
kong4580 0:3af3f05e8f7d 10 Mahony filter algorithms. Sketch runs on the 3.3 V 8 MHz Pro Mini and the Teensy 3.1.
kong4580 0:3af3f05e8f7d 11
kong4580 0:3af3f05e8f7d 12 SDA and SCL should have external pull-up resistors (to 3.3V).
kong4580 0:3af3f05e8f7d 13 10k resistors are on the EMSENSR-9250 breakout board.
kong4580 0:3af3f05e8f7d 14
kong4580 0:3af3f05e8f7d 15 Hardware setup:
kong4580 0:3af3f05e8f7d 16 MPU9250 Breakout --------- Arduino
kong4580 0:3af3f05e8f7d 17 VDD ---------------------- 3.3V
kong4580 0:3af3f05e8f7d 18 VDDI --------------------- 3.3V
kong4580 0:3af3f05e8f7d 19 SDA ----------------------- A4
kong4580 0:3af3f05e8f7d 20 SCL ----------------------- A5
kong4580 0:3af3f05e8f7d 21 GND ---------------------- GND
kong4580 0:3af3f05e8f7d 22
kong4580 0:3af3f05e8f7d 23 Note: The MPU9250 is an I2C sensor and uses the Arduino Wire library.
kong4580 0:3af3f05e8f7d 24 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.
kong4580 0:3af3f05e8f7d 25 We have disabled the internal pull-ups used by the Wire library in the Wire.h/twi.c utility file.
kong4580 0:3af3f05e8f7d 26 We are also using the 400 kHz fast I2C mode by setting the TWI_FREQ to 400000L /twi.h utility file.
kong4580 0:3af3f05e8f7d 27 */
kong4580 0:3af3f05e8f7d 28
kong4580 0:3af3f05e8f7d 29 //#include "ST_F401_84MHZ.h"
kong4580 0:3af3f05e8f7d 30 //F401_init84 myinit(0);
kong4580 0:3af3f05e8f7d 31 #include "mbed.h"
kong4580 0:3af3f05e8f7d 32 #include "MPU9250.h"
kong4580 0:3af3f05e8f7d 33
kong4580 0:3af3f05e8f7d 34 // Using NOKIA 5110 monochrome 84 x 48 pixel display
kong4580 0:3af3f05e8f7d 35 // pin 9 - Serial clock out (SCLK)
kong4580 0:3af3f05e8f7d 36 // pin 8 - Serial data out (DIN)
kong4580 0:3af3f05e8f7d 37 // pin 7 - Data/Command select (D/C)
kong4580 0:3af3f05e8f7d 38 // pin 5 - LCD chip select (CS)
kong4580 0:3af3f05e8f7d 39 // pin 6 - LCD reset (RST)
kong4580 0:3af3f05e8f7d 40 //Adafruit_PCD8544 display = Adafruit_PCD8544(9, 8, 7, 5, 6);
kong4580 0:3af3f05e8f7d 41
kong4580 0:3af3f05e8f7d 42 float sum = 0;
kong4580 0:3af3f05e8f7d 43 uint32_t sumCount = 0;
kong4580 0:3af3f05e8f7d 44 char buffer[14];
kong4580 0:3af3f05e8f7d 45
kong4580 0:3af3f05e8f7d 46 MPU9250 mpu9250;
kong4580 0:3af3f05e8f7d 47
kong4580 0:3af3f05e8f7d 48 Timer t;
kong4580 0:3af3f05e8f7d 49
kong4580 0:3af3f05e8f7d 50 Serial pc(USBTX, USBRX); // tx, rx
kong4580 0:3af3f05e8f7d 51
kong4580 0:3af3f05e8f7d 52 // VCC, SCE, RST, D/C, MOSI,S CLK, LED
kong4580 0:3af3f05e8f7d 53
kong4580 0:3af3f05e8f7d 54 DigitalIn boardbtn(USER_BUTTON);
kong4580 0:3af3f05e8f7d 55
kong4580 0:3af3f05e8f7d 56
kong4580 0:3af3f05e8f7d 57 int main()
kong4580 0:3af3f05e8f7d 58 {
kong4580 0:3af3f05e8f7d 59 pc.baud(9600);
kong4580 0:3af3f05e8f7d 60
kong4580 0:3af3f05e8f7d 61 //Set up I2C
kong4580 0:3af3f05e8f7d 62 i2c.frequency(400000); // use fast (400 kHz) I2C
kong4580 0:3af3f05e8f7d 63
kong4580 0:3af3f05e8f7d 64 // pc.printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);
kong4580 0:3af3f05e8f7d 65
kong4580 0:3af3f05e8f7d 66 t.start();
kong4580 0:3af3f05e8f7d 67
kong4580 0:3af3f05e8f7d 68
kong4580 0:3af3f05e8f7d 69
kong4580 0:3af3f05e8f7d 70
kong4580 0:3af3f05e8f7d 71 // Read the WHO_AM_I register, this is a good test of communication
kong4580 0:3af3f05e8f7d 72 uint8_t whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250); // Read WHO_AM_I register for MPU-9250
kong4580 0:3af3f05e8f7d 73 // pc.printf("I AM 0x%x\n\r", whoami);
kong4580 0:3af3f05e8f7d 74 // pc.printf("I SHOULD BE 0x71\n\r");
kong4580 0:3af3f05e8f7d 75
kong4580 0:3af3f05e8f7d 76 if (whoami == 0x71) { // WHO_AM_I should always be 0x68
kong4580 0:3af3f05e8f7d 77 // pc.printf("MPU9250 WHO_AM_I is 0x%x\n\r", whoami);
kong4580 0:3af3f05e8f7d 78 // pc.printf("MPU9250 is online...\n\r");
kong4580 0:3af3f05e8f7d 79
kong4580 0:3af3f05e8f7d 80 // sprintf(buffer, "0x%x", whoami);
kong4580 0:3af3f05e8f7d 81
kong4580 0:3af3f05e8f7d 82 wait(1);
kong4580 0:3af3f05e8f7d 83
kong4580 0:3af3f05e8f7d 84 mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
kong4580 0:3af3f05e8f7d 85 mpu9250.MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values
kong4580 0:3af3f05e8f7d 86 /* pc.printf("x-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[0]);
kong4580 0:3af3f05e8f7d 87 pc.printf("y-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[1]);
kong4580 0:3af3f05e8f7d 88 pc.printf("z-axis self test: acceleration trim within : %f % of factory value\n\r", SelfTest[2]);
kong4580 0:3af3f05e8f7d 89 pc.printf("x-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[3]);
kong4580 0:3af3f05e8f7d 90 pc.printf("y-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[4]);
kong4580 0:3af3f05e8f7d 91 pc.printf("z-axis self test: gyration trim within : %f % of factory value\n\r", SelfTest[5]);*/
kong4580 0:3af3f05e8f7d 92 if(boardbtn==0){
kong4580 0:3af3f05e8f7d 93 // wait(2);
kong4580 0:3af3f05e8f7d 94 mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers
kong4580 0:3af3f05e8f7d 95 pc.printf("x gyro bias = %f\n\r", gyroBias[0]);
kong4580 0:3af3f05e8f7d 96 pc.printf("y gyro bias = %f\n\r", gyroBias[1]);
kong4580 0:3af3f05e8f7d 97 pc.printf("z gyro bias = %f\n\r", gyroBias[2]);
kong4580 0:3af3f05e8f7d 98 pc.printf("x accel bias = %f\n\r", accelBias[0]);
kong4580 0:3af3f05e8f7d 99 pc.printf("y accel bias = %f\n\r", accelBias[1]);
kong4580 0:3af3f05e8f7d 100 pc.printf("z accel bias = %f\n\r", accelBias[2]);
kong4580 0:3af3f05e8f7d 101 wait(2);
kong4580 0:3af3f05e8f7d 102
kong4580 0:3af3f05e8f7d 103 ///*
kong4580 0:3af3f05e8f7d 104 // -----------------------------------------------------------------
kong4580 0:3af3f05e8f7d 105 }else{
kong4580 0:3af3f05e8f7d 106 gyroBias[0]=-1.244275;
kong4580 0:3af3f05e8f7d 107 gyroBias[1]=0.122137;
kong4580 0:3af3f05e8f7d 108 gyroBias[2]=-0.717557;
kong4580 0:3af3f05e8f7d 109 accelBias[0]=0.007996; // For Manual Calibate with button
kong4580 0:3af3f05e8f7d 110 accelBias[1]=0.021240;
kong4580 0:3af3f05e8f7d 111 accelBias[2]=-0.020508;
kong4580 0:3af3f05e8f7d 112 }
kong4580 0:3af3f05e8f7d 113 //------------------------------------------------------------------
kong4580 0:3af3f05e8f7d 114 //*/
kong4580 0:3af3f05e8f7d 115 mpu9250.initMPU9250();
kong4580 0:3af3f05e8f7d 116 // pc.printf("MPU9250 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
kong4580 0:3af3f05e8f7d 117 mpu9250.initAK8963(magCalibration);
kong4580 0:3af3f05e8f7d 118 /* pc.printf("AK8963 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
kong4580 0:3af3f05e8f7d 119 pc.printf("Accelerometer full-scale range = %f g\n\r", 2.0f*(float)(1<<Ascale));
kong4580 0:3af3f05e8f7d 120 pc.printf("Gyroscope full-scale range = %f deg/s\n\r", 250.0f*(float)(1<<Gscale));
kong4580 0:3af3f05e8f7d 121 if(Mscale == 0) pc.printf("Magnetometer resolution = 14 bits\n\r");
kong4580 0:3af3f05e8f7d 122 if(Mscale == 1) pc.printf("Magnetometer resolution = 16 bits\n\r");
kong4580 0:3af3f05e8f7d 123 if(Mmode == 2) pc.printf("Magnetometer ODR = 8 Hz\n\r");
kong4580 0:3af3f05e8f7d 124 if(Mmode == 6) pc.printf("Magnetometer ODR = 100 Hz\n\r");
kong4580 0:3af3f05e8f7d 125 wait(1);
kong4580 0:3af3f05e8f7d 126 */
kong4580 0:3af3f05e8f7d 127 } else {
kong4580 0:3af3f05e8f7d 128 pc.printf("Could not connect to MPU9250: \n\r");
kong4580 0:3af3f05e8f7d 129 pc.printf("%#x \n", whoami);
kong4580 0:3af3f05e8f7d 130
kong4580 0:3af3f05e8f7d 131
kong4580 0:3af3f05e8f7d 132 sprintf(buffer, "WHO_AM_I 0x%x", whoami);
kong4580 0:3af3f05e8f7d 133
kong4580 0:3af3f05e8f7d 134
kong4580 0:3af3f05e8f7d 135 while(1) ; // Loop forever if communication doesn't happen
kong4580 0:3af3f05e8f7d 136
kong4580 0:3af3f05e8f7d 137 }
kong4580 0:3af3f05e8f7d 138
kong4580 0:3af3f05e8f7d 139 mpu9250.getAres(); // Get accelerometer sensitivity
kong4580 0:3af3f05e8f7d 140 mpu9250.getGres(); // Get gyro sensitivity
kong4580 0:3af3f05e8f7d 141 mpu9250.getMres(); // Get magnetometer sensitivity
kong4580 0:3af3f05e8f7d 142 // pc.printf("Accelerometer sensitivity is %f LSB/g \n\r", 1.0f/aRes);
kong4580 0:3af3f05e8f7d 143 // pc.printf("Gyroscope sensitivity is %f LSB/deg/s \n\r", 1.0f/gRes);
kong4580 0:3af3f05e8f7d 144 // pc.printf("Magnetometer sensitivity is %f LSB/G \n\r", 1.0f/mRes);
kong4580 0:3af3f05e8f7d 145 magbias[0] = +470.; // User environmental x-axis correction in milliGauss, should be automatically calculated
kong4580 0:3af3f05e8f7d 146 magbias[1] = +120.; // User environmental x-axis correction in milliGauss
kong4580 0:3af3f05e8f7d 147 magbias[2] = +125.; // User environmental x-axis correction in milliGauss
kong4580 0:3af3f05e8f7d 148
kong4580 0:3af3f05e8f7d 149 while(1) {
kong4580 0:3af3f05e8f7d 150
kong4580 0:3af3f05e8f7d 151 // If intPin goes high, all data registers have new data
kong4580 0:3af3f05e8f7d 152 if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) { // On interrupt, check if data ready interrupt
kong4580 0:3af3f05e8f7d 153
kong4580 0:3af3f05e8f7d 154 mpu9250.readAccelData(accelCount); // Read the x/y/z adc values
kong4580 0:3af3f05e8f7d 155 // Now we'll calculate the accleration value into actual g's
kong4580 0:3af3f05e8f7d 156 ax = (float)accelCount[0]*aRes - accelBias[0]; // get actual g value, this depends on scale being set
kong4580 0:3af3f05e8f7d 157 ay = (float)accelCount[1]*aRes - accelBias[1];
kong4580 0:3af3f05e8f7d 158 az = (float)accelCount[2]*aRes - accelBias[2];
kong4580 0:3af3f05e8f7d 159
kong4580 0:3af3f05e8f7d 160 mpu9250.readGyroData(gyroCount); // Read the x/y/z adc values
kong4580 0:3af3f05e8f7d 161 // Calculate the gyro value into actual degrees per second
kong4580 0:3af3f05e8f7d 162 gx = (float)gyroCount[0]*gRes - gyroBias[0]; // get actual gyro value, this depends on scale being set
kong4580 0:3af3f05e8f7d 163 gy = (float)gyroCount[1]*gRes - gyroBias[1];
kong4580 0:3af3f05e8f7d 164 gz = (float)gyroCount[2]*gRes - gyroBias[2];
kong4580 0:3af3f05e8f7d 165
kong4580 0:3af3f05e8f7d 166 mpu9250.readMagData(magCount); // Read the x/y/z adc values
kong4580 0:3af3f05e8f7d 167 // Calculate the magnetometer values in milliGauss
kong4580 0:3af3f05e8f7d 168 // Include factory calibration per data sheet and user environmental corrections
kong4580 0:3af3f05e8f7d 169 mx = (float)magCount[0]*mRes*magCalibration[0] - magbias[0]; // get actual magnetometer value, this depends on scale being set
kong4580 0:3af3f05e8f7d 170 my = (float)magCount[1]*mRes*magCalibration[1] - magbias[1];
kong4580 0:3af3f05e8f7d 171 mz = (float)magCount[2]*mRes*magCalibration[2] - magbias[2];
kong4580 0:3af3f05e8f7d 172 }
kong4580 0:3af3f05e8f7d 173
kong4580 0:3af3f05e8f7d 174 Now = t.read_us();
kong4580 0:3af3f05e8f7d 175 deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
kong4580 0:3af3f05e8f7d 176 lastUpdate = Now;
kong4580 0:3af3f05e8f7d 177
kong4580 0:3af3f05e8f7d 178 sum += deltat;
kong4580 0:3af3f05e8f7d 179 sumCount++;
kong4580 0:3af3f05e8f7d 180
kong4580 0:3af3f05e8f7d 181 // if(lastUpdate - firstUpdate > 10000000.0f) {
kong4580 0:3af3f05e8f7d 182 // beta = 0.04; // decrease filter gain after stabilized
kong4580 0:3af3f05e8f7d 183 // zeta = 0.015; // increasey bias drift gain after stabilized
kong4580 0:3af3f05e8f7d 184 // }
kong4580 0:3af3f05e8f7d 185
kong4580 0:3af3f05e8f7d 186 // Pass gyro rate as rad/s
kong4580 0:3af3f05e8f7d 187 // mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
kong4580 0:3af3f05e8f7d 188 mpu9250.MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
kong4580 0:3af3f05e8f7d 189
kong4580 0:3af3f05e8f7d 190 // Serial print and/or display at 0.5 s rate independent of data rates
kong4580 0:3af3f05e8f7d 191 delt_t = t.read_ms() - count;
kong4580 0:3af3f05e8f7d 192 if (delt_t > 100) { // update LCD once per half-second independent of read rate
kong4580 0:3af3f05e8f7d 193
kong4580 0:3af3f05e8f7d 194 //pc.printf("ax = %f", 1000*ax);
kong4580 0:3af3f05e8f7d 195 //pc.printf(" ay = %f", 1000*ay);
kong4580 0:3af3f05e8f7d 196 // pc.printf(" az = %f mg\n\r", 1000*az);
kong4580 0:3af3f05e8f7d 197
kong4580 0:3af3f05e8f7d 198 // pc.printf("gx = %f", gx);
kong4580 0:3af3f05e8f7d 199 // pc.printf(" gy = %f", gy);
kong4580 0:3af3f05e8f7d 200 // pc.printf(" gz = %f deg/s\n\r", gz);
kong4580 0:3af3f05e8f7d 201
kong4580 0:3af3f05e8f7d 202 // pc.printf("gx = %f", mx);
kong4580 0:3af3f05e8f7d 203 // pc.printf(" gy = %f", my);
kong4580 0:3af3f05e8f7d 204 // pc.printf(" gz = %f mG\n\r", mz);
kong4580 0:3af3f05e8f7d 205
kong4580 0:3af3f05e8f7d 206 tempCount = mpu9250.readTempData(); // Read the adc values
kong4580 0:3af3f05e8f7d 207 temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade
kong4580 0:3af3f05e8f7d 208 // pc.printf(" temperature = %f C\n\r", temperature);
kong4580 0:3af3f05e8f7d 209 //
kong4580 0:3af3f05e8f7d 210 // pc.printf("q0 = %f\n\r", q[0]);
kong4580 0:3af3f05e8f7d 211 // pc.printf("q1 = %f\n\r", q[1]);
kong4580 0:3af3f05e8f7d 212 // pc.printf("q2 = %f\n\r", q[2]);
kong4580 0:3af3f05e8f7d 213 // pc.printf("q3 = %f\n\r", q[3]);
kong4580 0:3af3f05e8f7d 214
kong4580 0:3af3f05e8f7d 215 /* lcd.clear();
kong4580 0:3af3f05e8f7d 216 lcd.printString("MPU9250", 0, 0);
kong4580 0:3af3f05e8f7d 217 lcd.printString("x y z", 0, 1);
kong4580 0:3af3f05e8f7d 218 sprintf(buffer, "%d %d %d mg", (int)(1000.0f*ax), (int)(1000.0f*ay), (int)(1000.0f*az));
kong4580 0:3af3f05e8f7d 219 lcd.printString(buffer, 0, 2);
kong4580 0:3af3f05e8f7d 220 sprintf(buffer, "%d %d %d deg/s", (int)gx, (int)gy, (int)gz);
kong4580 0:3af3f05e8f7d 221 lcd.printString(buffer, 0, 3);
kong4580 0:3af3f05e8f7d 222 sprintf(buffer, "%d %d %d mG", (int)mx, (int)my, (int)mz);
kong4580 0:3af3f05e8f7d 223 lcd.printString(buffer, 0, 4);
kong4580 0:3af3f05e8f7d 224 */
kong4580 0:3af3f05e8f7d 225 // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
kong4580 0:3af3f05e8f7d 226 // In this coordinate system, the positive z-axis is down toward Earth.
kong4580 0:3af3f05e8f7d 227 // 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.
kong4580 0:3af3f05e8f7d 228 // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
kong4580 0:3af3f05e8f7d 229 // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
kong4580 0:3af3f05e8f7d 230 // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
kong4580 0:3af3f05e8f7d 231 // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be
kong4580 0:3af3f05e8f7d 232 // applied in the correct order which for this configuration is yaw, pitch, and then roll.
kong4580 0:3af3f05e8f7d 233 // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
kong4580 0:3af3f05e8f7d 234 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]);
kong4580 0:3af3f05e8f7d 235 pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
kong4580 0:3af3f05e8f7d 236 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]);
kong4580 0:3af3f05e8f7d 237 pitch *= 180.0f / PI;
kong4580 0:3af3f05e8f7d 238 yaw *= 180.0f / PI;
kong4580 0:3af3f05e8f7d 239 yaw -= 85.0f; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04
kong4580 0:3af3f05e8f7d 240 roll *= 180.0f / PI;
kong4580 0:3af3f05e8f7d 241
kong4580 0:3af3f05e8f7d 242 pc.printf("Yaw, Pitch, Roll: %f %f %f\n\r", yaw, pitch, roll);
kong4580 0:3af3f05e8f7d 243 // pc.printf("average rate = %f\n\r", (float) sumCount/sum);
kong4580 0:3af3f05e8f7d 244 // sprintf(buffer, "YPR: %f %f %f", yaw, pitch, roll);
kong4580 0:3af3f05e8f7d 245 // lcd.printString(buffer, 0, 4);
kong4580 0:3af3f05e8f7d 246 // sprintf(buffer, "rate = %f", (float) sumCount/sum);
kong4580 0:3af3f05e8f7d 247 // lcd.printString(buffer, 0, 5);
kong4580 0:3af3f05e8f7d 248
kong4580 0:3af3f05e8f7d 249 myled= !myled;
kong4580 0:3af3f05e8f7d 250 count = t.read_ms();
kong4580 0:3af3f05e8f7d 251
kong4580 0:3af3f05e8f7d 252 if(count > 1<<21) {
kong4580 0:3af3f05e8f7d 253 t.start(); // start the timer over again if ~30 minutes has passed
kong4580 0:3af3f05e8f7d 254 count = 0;
kong4580 0:3af3f05e8f7d 255 deltat= 0;
kong4580 0:3af3f05e8f7d 256 lastUpdate = t.read_us();
kong4580 0:3af3f05e8f7d 257 }
kong4580 0:3af3f05e8f7d 258 sum = 0;
kong4580 0:3af3f05e8f7d 259 sumCount = 0;
kong4580 0:3af3f05e8f7d 260 }
kong4580 0:3af3f05e8f7d 261 }
kong4580 0:3af3f05e8f7d 262
kong4580 0:3af3f05e8f7d 263 }