/*----------------------------------------------------------------------------- * Copyright (C) 2010 ARM Limited. All rights reserved. * * $Date: 29. November 2010 * $Revision: V1.0.3 * * Project: CMSIS DSP Library * Title: arm_fir_init_f32.c * * Description: Floating-point 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 floating-point 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. * * Description: * \par * pCoeffs points to the array of filter coefficients stored in time reversed order: *
  
 *    {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]}  
 * 
* \par * pState points to the array of state variables. * pState is of length numTaps+blockSize-1 samples, where blockSize is the number of input samples processed by each call to arm_fir_f32(). */ void arm_fir_init_f32( arm_fir_instance_f32 * S, uint16_t numTaps, float32_t * pCoeffs, float32_t * pState, uint32_t blockSize) { /* Assign filter taps */ S->numTaps = numTaps; /* Assign coefficient pointer */ S->pCoeffs = pCoeffs; /* Clear state buffer and the size of state buffer is (blockSize + numTaps - 1) */ memset(pState, 0, (numTaps + (blockSize - 1u)) * sizeof(float32_t)); /* Assign state pointer */ S->pState = pState; } /** * @} end of FIR group */