1 /*-----------------------------------------------------------------------------
2 * Copyright (C) 2010 ARM Limited. All rights reserved.
7 * Project: CMSIS DSP Library
8 * Title: arm_iir_lattice_init_q15.c
10 * Description: Q15 IIR lattice filter initialization function.
12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
14 * Version 1.0.10 2011/7/15
15 * Big Endian support added and Merged M0 and M3/M4 Source code.
17 * Version 1.0.3 2010/11/29
18 * Re-organized the CMSIS folders and updated documentation.
20 * Version 1.0.2 2010/11/11
21 * Documentation updated.
23 * Version 1.0.1 2010/10/05
24 * Production release and review comments incorporated.
26 * Version 1.0.0 2010/09/20
27 * Production release and review comments incorporated
29 * Version 0.0.7 2010/06/10
30 * Misra-C changes done
31 * ---------------------------------------------------------------------------*/
36 * @ingroup groupFilters
40 * @addtogroup IIR_Lattice
45 * @brief Initialization function for the Q15 IIR lattice filter.
46 * @param[in] *S points to an instance of the Q15 IIR lattice structure.
47 * @param[in] numStages number of stages in the filter.
48 * @param[in] *pkCoeffs points to reflection coefficient buffer. The array is of length numStages.
49 * @param[in] *pvCoeffs points to ladder coefficient buffer. The array is of length numStages+1.
50 * @param[in] *pState points to state buffer. The array is of length numStages+blockSize.
51 * @param[in] blockSize number of samples to process per call.
55 void arm_iir_lattice_init_q15(
56 arm_iir_lattice_instance_q15 * S,
63 /* Assign filter taps */
64 S->numStages = numStages;
66 /* Assign reflection coefficient pointer */
67 S->pkCoeffs = pkCoeffs;
69 /* Assign ladder coefficient pointer */
70 S->pvCoeffs = pvCoeffs;
72 /* Clear state buffer and size is always blockSize + numStages */
73 memset(pState, 0, (numStages + blockSize) * sizeof(q15_t));
75 /* Assign state pointer */
82 * @} end of IIR_Lattice group