Diff: src/Cortex-M4-M3/FilteringFunctions/arm_fir_init_q31.c

Revision:

0:1014af42efd9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Cortex-M4-M3/FilteringFunctions/arm_fir_init_q31.c	Thu Mar 10 15:07:50 2011 +0000
@@ -0,0 +1,88 @@
+/* ----------------------------------------------------------------------  
+* Copyright (C) 2010 ARM Limited. All rights reserved.  
+*  
+* $Date:        29. November 2010  
+* $Revision: 	V1.0.3  
+*  
+* Project: 	    CMSIS DSP Library  
+* Title:	    arm_fir_init_q31.c  
+*  
+* Description:	Q31 FIR filter 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 0.0.5  2010/04/26   
+* 	 incorporated review comments and updated with latest CMSIS layer  
+*  
+* Version 0.0.3  2010/03/10   
+*    Initial version  
+* -------------------------------------------------------------------- */ 
+ 
+#include "arm_math.h" 
+ 
+/**  
+ * @ingroup groupFilters  
+ */ 
+ 
+/**  
+ * @addtogroup FIR  
+ * @{  
+ */ 
+ 
+/**  
+ * @details  
+ *  
+ * @param[in,out] *S points to an instance of the Q31 FIR filter structure.  
+ * @param[in] 	  numTaps  Number of filter coefficients in the filter.  
+ * @param[in] 	  *pCoeffs points to the filter coefficients buffer.  
+ * @param[in] 	  *pState points to the state buffer.  
+ * @param[in] 	  blockSize number of samples that are processed per call.  
+ * @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>  
+ * \par  
+ * <code>pState</code> points to the array of state variables.  
+ * <code>pState</code> is 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_fir_q31()</code>.  
+ */ 
+ 
+void arm_fir_init_q31( 
+  arm_fir_instance_q31 * S, 
+  uint16_t numTaps, 
+  q31_t * pCoeffs, 
+  q31_t * pState, 
+  uint32_t blockSize) 
+{ 
+  /* Assign filter taps */ 
+  S->numTaps = numTaps; 
+ 
+  /* Assign coefficient pointer */ 
+  S->pCoeffs = pCoeffs; 
+ 
+  /* Clear state buffer and state array size is (blockSize + numTaps - 1) */ 
+  memset(pState, 0, (blockSize + ((uint32_t) numTaps - 1u)) * sizeof(q31_t)); 
+ 
+  /* Assign state pointer */ 
+  S->pState = pState; 
+ 
+} 
+ 
+/**  
+ * @} end of FIR group  
+ */