Andrew Miller
/
scoutTest
Quaternion calculations on data from PNI's SpacePoint Scout
main.cpp
- Committer:
- awmiller
- Date:
- 2013-01-02
- Revision:
- 0:5155f500559c
File content as of revision 0:5155f500559c:
#include "mbed.h" Serial pc(USBTX, USBRX); // tx, rx const int addr = 0x18; // define the I2C Address of the SpacepointRM union Quat_ci { short i[4]; char d[8]; } Quat; I2C i2c(p28, p27); // sda, scl int main() { pc.printf("Working... \n"); char cmd[1]; cmd[0] = (char) 0x31; i2c.write(addr,cmd,1); i2c.read(addr,Quat.d,8); char temp; temp = Quat.d[0]; Quat.d[0] = Quat.d[1];Quat.d[1]=temp; temp = Quat.d[2]; Quat.d[2] = Quat.d[3];Quat.d[3]=temp; temp = Quat.d[4]; Quat.d[4] = Quat.d[5];Quat.d[5]=temp; temp = Quat.d[6]; Quat.d[6] = Quat.d[7];Quat.d[7]=temp; float qx = (float)(Quat.i[0] - 32768)/32768; float qy = (float)(Quat.i[1] - 32768)/32768; float qz = (float)(Quat.i[2] - 32768)/32768; float qw = (float)(Quat.i[3] - 32768)/32768; //pc.printf("%d,%d,%d,%d \n",Quat.i[0],Quat.i[1],Quat.i[2],Quat.i[3]); pc.printf("%f,%f,%f,%f \n",qx,qy,qz,qw); float sqx = pow(qx , 2); float sqy = pow(qx , 2); float sqz = pow(qx , 2); float sqw = pow(qx , 2); float HEADING = atan2((2*((qx*qw)+(qy*qz))),(1-(2*(sqz+sqw)))); float PITCH = asin((2*((qx*qz) - (qw*qy))) ); float ROLL = atan2( (2*( (qx*qy) + (qz*qw) )) , (1-2*(sqy+sqz)) ); pc.printf("Heading: %f \n Pitch: %f \n Roll: %f \n",HEADING,PITCH,ROLL); }