00001 /*----------------------------------------------------------------------------- 00002 * Copyright (C) 2010 ARM Limited. All rights reserved. 00003 * 00004 * $Date: 15. July 2011 00005 * $Revision: V1.0.10 00006 * 00007 * Project: CMSIS DSP Library 00008 * Title: arm_fir_interpolate_init_q31.c 00009 * 00010 * Description: Q31 FIR interpolator initialization function 00011 * 00012 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 00013 * 00014 * Version 1.0.10 2011/7/15 00015 * Big Endian support added and Merged M0 and M3/M4 Source code. 00016 * 00017 * Version 1.0.3 2010/11/29 00018 * Re-organized the CMSIS folders and updated documentation. 00019 * 00020 * Version 1.0.2 2010/11/11 00021 * Documentation updated. 00022 * 00023 * Version 1.0.1 2010/10/05 00024 * Production release and review comments incorporated. 00025 * 00026 * Version 1.0.0 2010/09/20 00027 * Production release and review comments incorporated 00028 * 00029 * Version 0.0.7 2010/06/10 00030 * Misra-C changes done 00031 * ---------------------------------------------------------------------------*/ 00032 00033 #include "arm_math.h" 00034 00069 arm_status arm_fir_interpolate_init_q31( 00070 arm_fir_interpolate_instance_q31 * S, 00071 uint8_t L, 00072 uint16_t numTaps, 00073 q31_t * pCoeffs, 00074 q31_t * pState, 00075 uint32_t blockSize) 00076 { 00077 arm_status status; 00078 00079 /* The filter length must be a multiple of the interpolation factor */ 00080 if((numTaps % L) != 0u) 00081 { 00082 /* Set status as ARM_MATH_LENGTH_ERROR */ 00083 status = ARM_MATH_LENGTH_ERROR; 00084 } 00085 else 00086 { 00087 00088 /* Assign coefficient pointer */ 00089 S->pCoeffs = pCoeffs; 00090 00091 /* Assign Interpolation factor */ 00092 S->L = L; 00093 00094 /* Assign polyPhaseLength */ 00095 S->phaseLength = numTaps / L; 00096 00097 /* Clear state buffer and size of buffer is always phaseLength + blockSize - 1 */ 00098 memset(pState, 0, 00099 (blockSize + ((uint32_t) S->phaseLength - 1u)) * sizeof(q31_t)); 00100 00101 /* Assign state pointer */ 00102 S->pState = pState; 00103 00104 status = ARM_MATH_SUCCESS; 00105 } 00106 00107 return (status); 00108 00109 } 00110