Diff: ControllerFunctions/arm_sin_cos_q31.c

Revision:

0:3d9c67d97d6f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ControllerFunctions/arm_sin_cos_q31.c	Mon Jul 28 15:03:15 2014 +0000
@@ -0,0 +1,122 @@
+/* ----------------------------------------------------------------------    
+* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
+*    
+* $Date:        12. March 2014
+* $Revision: 	V1.4.3
+*    
+* Project: 	    CMSIS DSP Library    
+* Title:		arm_sin_cos_q31.c    
+*    
+* Description:	Cosine & Sine calculation for Q31 values.   
+*    
+* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
+*  
+* Redistribution and use in source and binary forms, with or without 
+* modification, are permitted provided that the following conditions
+* are met:
+*   - Redistributions of source code must retain the above copyright
+*     notice, this list of conditions and the following disclaimer.
+*   - Redistributions in binary form must reproduce the above copyright
+*     notice, this list of conditions and the following disclaimer in
+*     the documentation and/or other materials provided with the 
+*     distribution.
+*   - Neither the name of ARM LIMITED nor the names of its contributors
+*     may be used to endorse or promote products derived from this
+*     software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
+* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+* POSSIBILITY OF SUCH DAMAGE.    
+* -------------------------------------------------------------------- */
+
+#include "arm_math.h"
+#include "arm_common_tables.h"
+
+/**    
+ * @ingroup groupController    
+ */
+
+ /**    
+ * @addtogroup SinCos    
+ * @{    
+ */
+
+/**    
+ * @brief  Q31 sin_cos function.   
+ * @param[in]  theta    scaled input value in degrees    
+ * @param[out] *pSinVal points to the processed sine output.    
+ * @param[out] *pCosVal points to the processed cosine output.    
+ * @return none.   
+ *    
+ * The Q31 input value is in the range [-1 0.999999] and is mapped to a degree value in the range [-180 179].   
+ *    
+ */
+
+void arm_sin_cos_q31(
+  q31_t theta,
+  q31_t * pSinVal,
+  q31_t * pCosVal)
+{
+  q31_t fract;                                 /* Temporary variables for input, output */
+  uint16_t indexS, indexC;                     /* Index variable */
+  q31_t f1, f2, d1, d2;                        /* Two nearest output values */
+  q31_t Dn, Df;
+  q63_t temp;
+  
+  /* Calculate the nearest index */
+  indexS = (uint32_t)theta >> CONTROLLER_Q31_SHIFT;
+  indexC = (indexS + 128) & 0x1ff;
+
+  /* Calculation of fractional value */
+  fract = (theta - (indexS << CONTROLLER_Q31_SHIFT)) << 8;
+  
+  /* Read two nearest values of input value from the cos & sin tables */
+  f1 = sinTable_q31[indexC+0];
+  f2 = sinTable_q31[indexC+1];
+  d1 = -sinTable_q31[indexS+0];
+  d2 = -sinTable_q31[indexS+1];
+
+  Dn = 0x1921FB5; // delta between the two points (fixed), in this case 2*pi/FAST_MATH_TABLE_SIZE
+  Df = f2 - f1; // delta between the values of the functions
+  temp = Dn*((q63_t)d1 + d2);
+  temp = temp - ((q63_t)Df << 32);
+  temp = (q63_t)fract*(temp >> 31);
+  temp = temp + ((3*(q63_t)Df << 31) - (d2 + ((q63_t)d1 << 1))*Dn);
+  temp = (q63_t)fract*(temp >> 31);
+  temp = temp + (q63_t)d1*Dn;
+  temp = (q63_t)fract*(temp >> 31);
+
+  /* Calculation of cosine value */
+  *pCosVal = clip_q63_to_q31((temp >> 31) + (q63_t)f1);
+  
+  /* Read two nearest values of input value from the cos & sin tables */
+  f1 = sinTable_q31[indexS+0];
+  f2 = sinTable_q31[indexS+1];
+  d1 = sinTable_q31[indexC+0];
+  d2 = sinTable_q31[indexC+1];
+
+  Df = f2 - f1; // delta between the values of the functions
+  temp = Dn*((q63_t)d1 + d2);
+  temp = temp - ((q63_t)Df << 32);
+  temp = (q63_t)fract*(temp >> 31);
+  temp = temp + ((3*(q63_t)Df << 31) - (d2 + ((q63_t)d1 << 1))*Dn);
+  temp = (q63_t)fract*(temp >> 31);
+  temp = temp + (q63_t)d1*Dn;
+  temp = (q63_t)fract*(temp >> 31);
+  
+  /* Calculation of sine value */
+  *pSinVal = clip_q63_to_q31((temp >> 31) + (q63_t)f1);
+}
+
+/**    
+ * @} end of SinCos group    
+ */