Diff: src/Cortex-M4-M3/FilteringFunctions/arm_lms_norm_init_q31.c

Revision:

0:1014af42efd9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Cortex-M4-M3/FilteringFunctions/arm_lms_norm_init_q31.c	Thu Mar 10 15:07:50 2011 +0000
@@ -0,0 +1,100 @@
+/*-----------------------------------------------------------------------------  
+* Copyright (C) 2010 ARM Limited. All rights reserved.  
+*  
+* $Date:        29. November 2010  
+* $Revision: 	V1.0.3  
+*  
+* Project: 	    CMSIS DSP Library  
+* Title:        arm_lms_norm_init_q31.c  
+*  
+* Description:  Q31 NLMS initialization function.  
+*  
+* Target Processor: Cortex-M4/Cortex-M3
+*  
+* Version 1.0.3 2010/11/29 
+*    Re-organized the CMSIS folders and updated documentation.  
+*   
+* Version 1.0.2 2010/11/11  
+*    Documentation updated.   
+*  
+* Version 1.0.1 2010/10/05   
+*    Production release and review comments incorporated.  
+*  
+* Version 1.0.0 2010/09/20   
+*    Production release and review comments incorporated  
+*  
+* Version 0.0.7  2010/06/10   
+*    Misra-C changes done  
+* ---------------------------------------------------------------------------*/ 
+ 
+#include "arm_math.h" 
+#include "arm_common_tables.h" 
+ 
+/**  
+ * @addtogroup LMS_NORM  
+ * @{  
+ */ 
+ 
+  /**  
+   * @brief Initialization function for Q31 normalized LMS filter.  
+   * @param[in] *S points to an instance of the Q31 normalized LMS filter structure.  
+   * @param[in] numTaps  number of filter coefficients.  
+   * @param[in] *pCoeffs points to coefficient buffer.  
+   * @param[in] *pState points to state buffer.  
+   * @param[in] mu step size that controls filter coefficient updates.  
+   * @param[in] blockSize number of samples to process.  
+   * @param[in] postShift bit shift applied to coefficients.  
+   * @return none.  
+ *  
+ * <b>Description:</b>  
+ * \par  
+ * <code>pCoeffs</code> points to the array of filter coefficients stored in time reversed order:  
+ * <pre>  
+ *    {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]}  
+ * </pre>  
+ * The initial filter coefficients serve as a starting point for the adaptive filter.  
+ * <code>pState</code> points to an array of length <code>numTaps+blockSize-1</code> samples,  
+ * where <code>blockSize</code> is the number of input samples processed by each call to <code>arm_lms_norm_q31()</code>.  
+ */ 
+ 
+void arm_lms_norm_init_q31( 
+  arm_lms_norm_instance_q31 * S, 
+  uint16_t numTaps, 
+  q31_t * pCoeffs, 
+  q31_t * pState, 
+  q31_t mu, 
+  uint32_t blockSize, 
+  uint8_t postShift) 
+{ 
+  /* Assign filter taps */ 
+  S->numTaps = numTaps; 
+ 
+  /* Assign coefficient pointer */ 
+  S->pCoeffs = pCoeffs; 
+ 
+  /* Clear state buffer and size is always blockSize + numTaps - 1  */ 
+  memset(pState, 0, (numTaps + (blockSize - 1u)) * sizeof(q31_t)); 
+ 
+  /* Assign post Shift value applied to coefficients */ 
+  S->postShift = postShift; 
+ 
+  /* Assign state pointer */ 
+  S->pState = pState; 
+ 
+  /* Assign Step size value */ 
+  S->mu = mu; 
+ 
+  /* Initialize reciprocal pointer table */ 
+  S->recipTable = (q31_t*)armRecipTableQ31; 
+ 
+  /* Initialise Energy to zero */ 
+  S->energy = 0; 
+ 
+  /* Initialise x0 to zero */ 
+  S->x0 = 0; 
+ 
+} 
+ 
+/**  
+ * @} end of LMS_NORM group  
+ */