A quick and dirty demo of the Xadow M0 acceleromoeter values displayed on the Xadow OLED 0.96" (using the SSD1308 128x64 OLED Driver with I2C interface library).

Dependencies:   mbed SSD1308_128x64_I2C_opt XadowGPS BMP180 ADXL345_I2C MPU9250 USBDevice

Revision:
5:50051611b5bd
Parent:
2:7abdbccdf0c8
Child:
7:4931dbfbc042
--- a/main.cpp	Sun Jan 10 18:22:26 2016 +0000
+++ b/main.cpp	Tue Jun 12 08:23:33 2018 +0000
@@ -3,8 +3,10 @@
 
 #include "ADXL345_I2C.h"
 #include "SSD1308.h"
+#include "MPU9250.h"
+#include "BMP180.h"
 
-//#define DEBUG
+#define DEBUG
 
 #ifdef DEBUG
 #include "USBSerial.h"                       // To use USB virtual serial, a driver is needed, check http://mbed.org/handbook/USBSerial
@@ -20,6 +22,13 @@
 // Xhadow - OLED 128x64 is connected with I2C
 I2C i2c(P0_5, P0_4);    // SDA, SCL
 SSD1308 oled = SSD1308(i2c, SSD1308_SA0);
+SSD1308 oled2 = SSD1308(i2c, SSD1308_SA1);
+
+// MPU9250 9DOF IMU - accelerometer, gyroscope, magnetometer access class
+MPU9250 mpu9250(i2c);
+
+// BMP180 pressure and temperature sensor access class
+BMP180 bmp180(&i2c);
 
 AnalogIn AD00(P0_11);
 AnalogIn AD01(P0_12);
@@ -37,6 +46,246 @@
     Bus3V3En = !Bus3V3En;
 }
 
+void MPU9250Test()
+{
+    Timer t;
+    float sum = 0;
+    uint32_t sumCount = 0;
+
+    char buffer[14];
+
+    uint8_t whoami;
+    
+  //___ Set up I2C: use fast (400 kHz) I2C ___
+  i2c.frequency(400000);  
+  
+    wait(10); // to allow terminal to cooect on PC
+  
+  while(1) {
+    if (bmp180.init() != 0) {
+      LOG("Error communicating with BMP180r\n");
+    } else {
+      LOG("Initialized BMP180r\n");
+      break;
+    }
+    wait(1);
+  }
+  
+  LOG("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);
+  
+  t.start(); // Timer ON
+  
+  // Read the WHO_AM_I register, this is a good test of communication
+  whoami = mpu9250.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250);
+  
+  LOG("I AM 0x%x\r\n", whoami); LOG("I SHOULD BE 0x71\r\n");
+  if (I2Cstate != 0) // error on I2C
+    LOG("I2C failure while reading WHO_AM_I register");
+  
+  if (whoami == 0x71) // WHO_AM_I should always be 0x71
+  {  
+    LOG("MPU9250 WHO_AM_I is 0x%x\r\n", whoami);
+    LOG("MPU9250 is online...\r\n");
+    sprintf(buffer, "0x%x", whoami);
+    wait(1);
+    
+    mpu9250.resetMPU9250(); // Reset registers to default in preparation for device calibration
+    
+    mpu9250.MPU9250SelfTest(SelfTest); // Start by performing self test and reporting values (accelerometer and gyroscope self test)
+    LOG("x-axis self test: acceleration trim within : %f % of factory value\r\n", SelfTest[0]);
+    LOG("y-axis self test: acceleration trim within : %f % of factory value\r\n", SelfTest[1]);
+    LOG("z-axis self test: acceleration trim within : %f % of factory value\r\n", SelfTest[2]);
+    LOG("x-axis self test: gyration trim within : %f % of factory value\r\n", SelfTest[3]);
+    LOG("y-axis self test: gyration trim within : %f % of factory value\r\n", SelfTest[4]);
+    LOG("z-axis self test: gyration trim within : %f % of factory value\r\n", SelfTest[5]);
+    
+    mpu9250.calibrateMPU9250(gyroBias, accelBias); // Calibrate gyro and accelerometer, load biases in bias registers  
+    LOG("x gyro bias = %f\r\n", gyroBias[0]);
+    LOG("y gyro bias = %f\r\n", gyroBias[1]);
+    LOG("z gyro bias = %f\r\n", gyroBias[2]);
+    LOG("x accel bias = %f\r\n", accelBias[0]);
+    LOG("y accel bias = %f\r\n", accelBias[1]);
+    LOG("z accel bias = %f\r\n", accelBias[2]);
+    wait(2);
+    
+    // Initialize device for active mode read of acclerometer, gyroscope, and temperature
+    mpu9250.initMPU9250();
+    LOG("MPU9250 initialized for active data mode....\r\n");
+    
+    // Initialize device for active mode read of magnetometer, 16 bit resolution, 100Hz.
+    mpu9250.initAK8963(magCalibration);
+    LOG("AK8963 initialized for active data mode....\r\n");
+    LOG("Accelerometer full-scale range = %f  g\r\n", 2.0f*(float)(1<<Ascale));
+    LOG("Gyroscope full-scale range = %f  deg/s\r\n", 250.0f*(float)(1<<Gscale));
+    if(Mscale == 0) LOG("Magnetometer resolution = 14  bits\r\n");
+    if(Mscale == 1) LOG("Magnetometer resolution = 16  bits\r\n");
+    if(Mmode == 2) LOG("Magnetometer ODR = 8 Hz\r\n");
+    if(Mmode == 6) LOG("Magnetometer ODR = 100 Hz\r\n");
+    wait(1);
+   }
+   
+   else // Connection failure
+   {
+    LOG("Could not connect to MPU9250: \r\n");
+    LOG("%#x \n",  whoami);    
+    sprintf(buffer, "WHO_AM_I 0x%x", whoami);
+    while(1) ; // Loop forever if communication doesn't happen
+    }
+  
+    mpu9250.getAres(); // Get accelerometer sensitivity
+    mpu9250.getGres(); // Get gyro sensitivity
+    mpu9250.getMres(); // Get magnetometer sensitivity
+    LOG("Accelerometer sensitivity is %f LSB/g \r\n", 1.0f/aRes);
+    LOG("Gyroscope sensitivity is %f LSB/deg/s \r\n", 1.0f/gRes);
+    LOG("Magnetometer sensitivity is %f LSB/G \r\n", 1.0f/mRes);
+    magbias[0] = +470.;  // User environmental x-axis correction in milliGauss, should be automatically calculated
+    magbias[1] = +120.;  // User environmental x-axis correction in milliGauss
+    magbias[2] = +125.;  // User environmental x-axis correction in milliGauss
+    
+    while(1) {
+      
+        // If intPin goes high, all data registers have new data
+        if(mpu9250.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01) {  // On interrupt, check if data ready interrupt
+              
+            mpu9250.readAccelData(accelCount);  // Read the x/y/z adc values   
+            // Now we'll calculate the accleration value into actual g's
+            if (I2Cstate != 0) //error on I2C
+                LOG("I2C error ocurred while reading accelerometer data. I2Cstate = %d \r\n", I2Cstate);
+            else{ // I2C read or write ok
+                I2Cstate = 1;
+                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
+            if (I2Cstate != 0) //error on I2C
+                LOG("I2C error ocurred while reading gyrometer data. I2Cstate = %d \r\n", I2Cstate);
+            else{ // I2C read or write ok
+                I2Cstate = 1;
+                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
+            if (I2Cstate != 0) //error on I2C
+                LOG("I2C error ocurred while reading magnetometer data. I2Cstate = %d \r\n", I2Cstate);
+            else{ // I2C read or write ok
+                I2Cstate = 1;
+                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];
+            }
+                       
+            mpu9250.getCompassOrientation(orientation);
+        }
+   
+        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++;
+    
+        // Pass gyro rate as rad/s
+        // mpu9250.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f,  my,  mx, mz);
+        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 1.5 s rate independent of data rates
+        delt_t = t.read_ms() - count;
+        if (delt_t > 1500) { // update LCD once per half-second independent of read rate
+            LOG("ax = %f", 1000*ax);
+            LOG(" ay = %f", 1000*ay);
+            LOG(" az = %f  mg\r\n", 1000*az);
+            LOG("gx = %f", gx);
+            LOG(" gy = %f", gy);
+            LOG(" gz = %f  deg/s\r\n", gz);
+            LOG("mx = %f", mx); 
+            LOG(" my = %f", my); 
+            LOG(" mz = %f  mG\r\n", mz);
+            
+
+            tempCount = mpu9250.readTempData();  // Read the adc values
+            if (I2Cstate != 0) //error on I2C
+                LOG("I2C error ocurred while reading sensor temp. I2Cstate = %d \r\n", I2Cstate);
+            else{ // I2C read or write ok                
+                I2Cstate = 1;
+                temperature = ((float) tempCount) / 333.87f + 21.0f; // Temperature in degrees Centigrade
+                LOG(" temperature = %f  C\r\n", temperature);
+            }
+            LOG("q0 = %f\r\n", q[0]);
+            LOG("q1 = %f\r\n", q[1]);
+            LOG("q2 = %f\r\n", q[2]);
+            LOG("q3 = %f\r\n", q[3]);
+            
+            LOG("Compass orientation: %f\r\n", orientation[0]);
+    
+            
+            
+            
+            // 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;
+
+            
+            LOG("Yaw, Pitch, Roll: %f %f %f\r\n", yaw, pitch, roll);
+            LOG("average rate = %f\r\n", (float) sumCount/sum);
+            
+            
+    
+            myled= !myled;
+            count = t.read_ms(); 
+
+            if(count > 1<<21) {
+                t.start(); // start the timer over again if ~30 minutes has passed
+                count = 0;
+                deltat= 0;
+                lastUpdate = t.read_us();
+            }
+        sum = 0;
+        sumCount = 0; 
+
+    //BMP180        
+            bmp180.startTemperature();
+            wait_ms(5);     // Wait for conversion to complete
+            float temp;
+            if(bmp180.getTemperature(&temp) != 0) {
+                LOG("Error getting temperature\n");
+                continue;
+            }
+     
+            bmp180.startPressure(BMP180::ULTRA_LOW_POWER);
+            wait_ms(10);    // Wait for conversion to complete
+            int pressure;
+            if(bmp180.getPressure(&pressure) != 0) {
+                LOG("Error getting pressure\n");
+                continue;
+            }
+     
+            LOG("Pressure = %d Pa Temperature = %f C\r\n", pressure, temp);
+
+        }
+    }
+}
+
 int main()
 {
     int readings[MAX_ACC_AXIS] = {0, 0, 0};
@@ -47,9 +296,31 @@
     
     test_int.rise(test_pin_int);
 
+    MPU9250Test();
+
     LOG("Starting ADXL345 test...\n");
     LOG("Device ID is: 0x%02x\n", accelerometer.getDeviceID());
 
+/* // Simple OLED speed test
+    oled.fillDisplay(0xAA);
+    oled.writeBigChar(1,0,'6');
+
+    uint8_t cnt=0;
+    int cycl=0;
+    while(1){
+        snprintf(display_buf, sizeof(display_buf), "%5i", cnt++);
+        oled.writeString(0, 0, display_buf);
+        if (0==cnt) {
+            ++cycl;
+            snprintf(display_buf, sizeof(display_buf), "%5i", cycl);
+            oled.writeString(1, 0, display_buf);
+        }
+    }
+*/
+    oled2.writeString(0, 0, "OLED 2:");
+    oled2.writeString(1, 0, "GEEKCREIT");
+    oled2.writeString(2, 0, "Banggood 0x7A");
+
     oled.writeString(0, 0, "Accelerometer:");
     oled.writeString(1, 0, "  Curr  Min  Max");