CMSIS DSP library
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Diff: cmsis_dsp/FilteringFunctions/arm_iir_lattice_init_q15.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/FilteringFunctions/arm_iir_lattice_init_q15.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,86 @@ +/*----------------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_iir_lattice_init_q15.c +* +* Description: Q15 IIR lattice filter initialization function. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* Version 1.0.10 2011/7/15 +* Big Endian support added and Merged M0 and M3/M4 Source code. +* +* 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" + +/** + * @ingroup groupFilters + */ + +/** + * @addtogroup IIR_Lattice + * @{ + */ + + /** + * @brief Initialization function for the Q15 IIR lattice filter. + * @param[in] *S points to an instance of the Q15 IIR lattice structure. + * @param[in] numStages number of stages in the filter. + * @param[in] *pkCoeffs points to reflection coefficient buffer. The array is of length numStages. + * @param[in] *pvCoeffs points to ladder coefficient buffer. The array is of length numStages+1. + * @param[in] *pState points to state buffer. The array is of length numStages+blockSize. + * @param[in] blockSize number of samples to process per call. + * @return none. + */ + +void arm_iir_lattice_init_q15( + arm_iir_lattice_instance_q15 * S, + uint16_t numStages, + q15_t * pkCoeffs, + q15_t * pvCoeffs, + q15_t * pState, + uint32_t blockSize) +{ + /* Assign filter taps */ + S->numStages = numStages; + + /* Assign reflection coefficient pointer */ + S->pkCoeffs = pkCoeffs; + + /* Assign ladder coefficient pointer */ + S->pvCoeffs = pvCoeffs; + + /* Clear state buffer and size is always blockSize + numStages */ + memset(pState, 0, (numStages + blockSize) * sizeof(q15_t)); + + /* Assign state pointer */ + S->pState = pState; + + +} + +/** + * @} end of IIR_Lattice group + */