An example program that decodes the data returned from the MPU9150 DMP

Dependencies:   CMSIS_DSP_401 MPU9150_DMP QuaternionMath mbed

Fork of MPU9150_Example by Chris Pepper

main.cpp

Committer:
Hagrass
Date:
2015-08-11
Revision:
1:b213291e5a51
Parent:
0:9f2982964a48

File content as of revision 1:b213291e5a51:

#include "MPU9150.h"
#include "Quaternion.h"

Serial debug(USBTX, USBRX);
MPU9150 imu(p27, p28, p15);

DigitalOut led(LED1);

char buffer[200];

int main(){
    debug.baud(115200);
    
    if(imu.isReady()){
        debug.printf("MPU9150 is ready\r\n");
    } else {
        debug.printf("MPU9150 initialisation failure\r\n");
    }
    
    imu.initialiseDMP();

    Timer timer;
    timer.start();

    imu.setFifoReset(true);    
    imu.setDMPEnabled(true);    
    
    Quaternion q1;
    
    while(true){
        
    wait(1);
    

        if(imu.getFifoCount() >= 48){
            imu.getFifoBuffer(buffer,  48);
            led = !led;
        }
        q1.decode(buffer);
    //    wait(1.1);
        if(timer.read_ms() >50){
            timer.reset();
           
           //This is the format of the data in the fifo, 
           /* ================================================================================================ *
             | Default MotionApps v4.1 48-byte FIFO packet structure:                                           |
             |                                                                                                  |
             | [QUAT W][      ][QUAT X][      ][QUAT Y][      ][QUAT Z][      ][GYRO X][      ][GYRO Y][      ] |
             |   0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  |
             |                                                                                                  |
             | [GYRO Z][      ][MAG X ][MAG Y ][MAG Z ][ACC X ][      ][ACC Y ][      ][ACC Z ][      ][      ] |
             |  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  |
             * ================================================================================================ */
             
            /*
            debug.printf("%d, %d, %d\r\n",  (int32_t)(((int32_t)buffer[34] << 24) + ((int32_t)buffer[35] << 16) + ((int32_t)buffer[36] << 8) + (int32_t)buffer[37]), 
                                            (int32_t)(((int32_t)buffer[38] << 24) + ((int32_t)buffer[39] << 16) + ((int32_t)buffer[40] << 8) + (int32_t)buffer[41]), 
                                            (int32_t)(((int32_t)buffer[42] << 24) + ((int32_t)buffer[43] << 16) + ((int32_t)buffer[44] << 8) + (int32_t)buffer[45]));
                                                
            debug.printf("%d, %d, %d\r\n",  (int32_t)(((int32_t)buffer[16] << 24) + ((int32_t)buffer[17] << 16) + ((int32_t)buffer[18] << 8) + (int32_t)buffer[19]),
                                            (int32_t)(((int32_t)buffer[20] << 24) + ((int32_t)buffer[21] << 16) + ((int32_t)buffer[22] << 8) + (int32_t)buffer[23]),
                                            (int32_t)(((int32_t)buffer[24] << 24) + ((int32_t)buffer[25] << 16) + ((int32_t)buffer[26] << 8) + (int32_t)buffer[27]));
                                            
            debug.printf("%d, %d, %d\r\n",  (int16_t)(buffer[29] << 8) + buffer[28], 
                                            (int16_t)(buffer[31] << 8) + buffer[30], 
                                            (int16_t)(buffer[33] << 8) + buffer[32]);
                                            
            debug.printf("%f, %f, %f, %f\r\n", 
                (float)((((int32_t)buffer[0] << 24) + ((int32_t)buffer[1] << 16) + ((int32_t)buffer[2] << 8) + buffer[3]))* (1.0 / (1<<30)),
                (float)((((int32_t)buffer[4] << 24) + ((int32_t)buffer[5] << 16) + ((int32_t)buffer[6] << 8) + buffer[7]))* (1.0 / (1<<30)),
                (float)((((int32_t)buffer[8] << 24) + ((int32_t)buffer[9] << 16) + ((int32_t)buffer[10] << 8) + buffer[11]))* (1.0 / (1<<30)),
                (float)((((int32_t)buffer[12] << 24) + ((int32_t)buffer[13] << 16) + ((int32_t)buffer[14] << 8) + buffer[15]))* (1.0 / (1<<30)));
            */
                //wait(0.01); 
            
            debug.printf("w:%f, v.x:%f, v.y:%f, v.z:%f\r\n", q1.w, q1.v.x, q1.v.y, q1.v.z);
imu.setFifoReset(true);    
    imu.setDMPEnabled(true);

            //TeaPot Demo Packet for MotionFit SDK
            /*
            debug.putc('$'); //packet start
            debug.putc((char)2); //assume packet type constant
            debug.putc((char)0); //count seems unused
            for(int i = 0; i < 16; i++){ //16 bytes for 4 32bit floats
                debug.putc((char)(buffer[i]));
            }
            for(int i = 0; i < 5; i++){ //no idea, padded with 0
                debug.putc((char)0);
            }
            */
        
        }   
   
  }
}