00001 /* ---------------------------------------------------------------------- 00002 * Copyright (C) 2010 ARM Limited. All rights reserved. 00003 * 00004 * $Date: 29. November 2010 00005 * $Revision: V1.0.3 00006 * 00007 * Project: CMSIS DSP Library 00008 * Title: arm_fir_init_q15.c 00009 * 00010 * Description: Q15 FIR filter initialization function. 00011 * 00012 * Target Processor: Cortex-M4/Cortex-M3 00013 * 00014 * Version 1.0.3 2010/11/29 00015 * Re-organized the CMSIS folders and updated documentation. 00016 * 00017 * Version 1.0.2 2010/11/11 00018 * Documentation updated. 00019 * 00020 * Version 1.0.1 2010/10/05 00021 * Production release and review comments incorporated. 00022 * 00023 * Version 1.0.0 2010/09/20 00024 * Production release and review comments incorporated. 00025 * 00026 * Version 0.0.5 2010/04/26 00027 * incorporated review comments and updated with latest CMSIS layer 00028 * 00029 * Version 0.0.3 2010/03/10 00030 * Initial version 00031 * ------------------------------------------------------------------- */ 00032 00033 #include "arm_math.h" 00034 00082 arm_status arm_fir_init_q15( 00083 arm_fir_instance_q15 * S, 00084 uint16_t numTaps, 00085 q15_t * pCoeffs, 00086 q15_t * pState, 00087 uint32_t blockSize) 00088 { 00089 arm_status status; 00090 00091 /* The Number of filter coefficients in the filter must be even and at least 4 */ 00092 if((numTaps < 4u) || (numTaps & 0x1u)) 00093 { 00094 status = ARM_MATH_ARGUMENT_ERROR; 00095 } 00096 else 00097 { 00098 /* Assign filter taps */ 00099 S->numTaps = numTaps; 00100 00101 /* Assign coefficient pointer */ 00102 S->pCoeffs = pCoeffs; 00103 00104 /* Clear the state buffer. The size is always (blockSize + numTaps - 1) */ 00105 memset(pState, 0, (numTaps + (blockSize - 1u)) * sizeof(q15_t)); 00106 00107 /* Assign state pointer */ 00108 S->pState = pState; 00109 00110 status = ARM_MATH_SUCCESS; 00111 } 00112 00113 return (status); 00114 } 00115