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Diffstat (limited to 'platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c')
| -rw-r--r-- | platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c b/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c new file mode 100644 index 0000000..210a317 --- /dev/null +++ b/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_q15.c @@ -0,0 +1,189 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2014 ARM Limited. All rights reserved. +* +* $Date: 31. July 2014 +* $Revision: V1.4.4 +* +* 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 +* +* Redistribution and use in source and binary forms, with or without +* modification, are permitted provided that the following conditions +* are met: +* - Redistributions of source code must retain the above copyright +* notice, this list of conditions and the following disclaimer. +* - Redistributions in binary form must reproduce the above copyright +* notice, this list of conditions and the following disclaimer in +* the documentation and/or other materials provided with the +* distribution. +* - Neither the name of ARM LIMITED nor the names of its contributors +* may be used to endorse or promote products derived from this +* software without specific prior written permission. +* +* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +* POSSIBILITY OF SUCH DAMAGE. +* -------------------------------------------------------------------- */ + +#include "arm_math.h" +#include "arm_common_tables.h" + +/** + * @ingroup groupTransforms + */ + + +/** + * @addtogroup ComplexFFT + * @{ + */ + +/** +* @brief Initialization function for the Q15 CFFT/CIFFT. +* @deprecated Do not use this function. It has been superseded by \ref arm_cfft_q15 and will be removed +* @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 <code>fftLen</code> is not a supported value. +* +* \par Description: +* \par +* The parameter <code>ifftFlag</code> controls whether a forward or inverse transform is computed. +* Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated +* \par +* The parameter <code>bitReverseFlag</code> 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 <code>fftLen</code> 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 *) twiddleCoef_4096_q15; + /* 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 ComplexFFT group + */ |