void MyCDCBasicTasks()
{
    if( USBUSARTIsTxTrfReady() == true)
    {
        uint8_t i,j,k;
        uint8_t numBytesRead;
        unsigned char FIN[5][20];
        double X1,X2,X3;
        numBytesRead = getsUSBUSART(readBuffer, sizeof(readBuffer));

        if(numBytesRead > 0)
        {
            j=0;k=0;
            for(i=0;i5){j=4;}
                    k=0;
                }
                else
                {
                    FIN[j][k]=readBuffer[i];
                    k++;if(k>20){k=19;}
                }
            }
            if(FIN[0][0]=='A' && FIN[0][1]=='A' && FIN[0][2]==0)
            {
                X1=atof((const char *)FIN[1]);
                X2=atof((const char *)FIN[2]);
                X3=X1+X2;

                sprintf(writeBuffer,"%.2f + %.2f = %.2f\r\n",X1,X2,X3);
                numBytesRead = strlen(writeBuffer);
                putUSBUSART(writeBuffer,numBytesRead);
            }
        }
    }
    CDCTxService();
}