From 4447282260be0780eb6e36f5e953bf56888a5688 Mon Sep 17 00:00:00 2001 From: px4dev Date: Sun, 6 Jan 2013 12:52:05 -0800 Subject: Integrate the interesting parts of the CMSIS 3.01 (r3p1) DSP library --- .../TransformFunctions/arm_cfft_radix2_init_q15.c | 186 +++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c (limited to 'apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c') diff --git a/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c b/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c new file mode 100644 index 000000000..86aa149b2 --- /dev/null +++ b/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c @@ -0,0 +1,186 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_cfft_radix2_init_q15.c +* +* Description: Radix-2 Decimation in Frequency Q15 FFT & IFFT 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 0.0.5 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" +#include "arm_common_tables.h" + +/** + * @ingroup groupTransforms + */ + + +/** + * @addtogroup Radix2_CFFT_CIFFT + * @{ + */ + +/** +* @brief Initialization function for the Q15 CFFT/CIFFT. +* @param[in,out] *S points to an instance of the Q15 CFFT/CIFFT structure. +* @param[in] fftLen length of the FFT. +* @param[in] ifftFlag flag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform. +* @param[in] bitReverseFlag flag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output. +* @return The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value. +* +* \par Description: +* \par +* The parameter ifftFlag controls whether a forward or inverse transform is computed. +* Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated +* \par +* The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. +* Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order. +* \par +* The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024. +* \par +* This Function also initializes Twiddle factor table pointer and Bit reversal table pointer. +*/ + +arm_status arm_cfft_radix2_init_q15( + arm_cfft_radix2_instance_q15 * S, + uint16_t fftLen, + uint8_t ifftFlag, + uint8_t bitReverseFlag) +{ + /* Initialise the default arm status */ + arm_status status = ARM_MATH_SUCCESS; + + /* Initialise the FFT length */ + S->fftLen = fftLen; + + /* Initialise the Twiddle coefficient pointer */ + S->pTwiddle = (q15_t *) twiddleCoefQ15; + /* Initialise the Flag for selection of CFFT or CIFFT */ + S->ifftFlag = ifftFlag; + /* Initialise the Flag for calculation Bit reversal or not */ + S->bitReverseFlag = bitReverseFlag; + + /* Initializations of structure parameters depending on the FFT length */ + switch (S->fftLen) + { + case 4096u: + /* Initializations of structure parameters for 4096 point FFT */ + + /* Initialise the twiddle coef modifier value */ + S->twidCoefModifier = 1u; + /* Initialise the bit reversal table modifier */ + S->bitRevFactor = 1u; + /* Initialise the bit reversal table pointer */ + S->pBitRevTable = (uint16_t *) armBitRevTable; + + break; + + case 2048u: + /* Initializations of structure parameters for 2048 point FFT */ + + /* Initialise the twiddle coef modifier value */ + S->twidCoefModifier = 2u; + /* Initialise the bit reversal table modifier */ + S->bitRevFactor = 2u; + /* Initialise the bit reversal table pointer */ + S->pBitRevTable = (uint16_t *) & armBitRevTable[1]; + + break; + + case 1024u: + /* Initializations of structure parameters for 1024 point FFT */ + S->twidCoefModifier = 4u; + S->bitRevFactor = 4u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[3]; + + break; + + case 512u: + /* Initializations of structure parameters for 512 point FFT */ + S->twidCoefModifier = 8u; + S->bitRevFactor = 8u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[7]; + + break; + + case 256u: + /* Initializations of structure parameters for 256 point FFT */ + S->twidCoefModifier = 16u; + S->bitRevFactor = 16u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[15]; + + break; + + case 128u: + /* Initializations of structure parameters for 128 point FFT */ + S->twidCoefModifier = 32u; + S->bitRevFactor = 32u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[31]; + + break; + + case 64u: + /* Initializations of structure parameters for 64 point FFT */ + S->twidCoefModifier = 64u; + S->bitRevFactor = 64u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[63]; + + break; + + case 32u: + /* Initializations of structure parameters for 32 point FFT */ + S->twidCoefModifier = 128u; + S->bitRevFactor = 128u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[127]; + + break; + + case 16u: + /* Initializations of structure parameters for 16 point FFT */ + S->twidCoefModifier = 256u; + S->bitRevFactor = 256u; + S->pBitRevTable = (uint16_t *) & armBitRevTable[255]; + + break; + + default: + /* Reporting argument error if fftSize is not valid value */ + status = ARM_MATH_ARGUMENT_ERROR; + break; + } + + return (status); +} + +/** + * @} end of Radix2_CFFT_CIFFT group + */ -- cgit v1.2.3