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Diffstat (limited to 'apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_f32.c')
-rw-r--r-- | apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_f32.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_f32.c b/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_f32.c new file mode 100644 index 000000000..a41ed25d2 --- /dev/null +++ b/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_init_f32.c @@ -0,0 +1,198 @@ +/* ----------------------------------------------------------------------
+* Copyright (C) 2010 ARM Limited. All rights reserved.
+*
+* $Date: 15. February 2012
+* $Revision: V1.1.0
+*
+* Project: CMSIS DSP Library
+* Title: arm_cfft_radix4_init_f32.c
+*
+* Description: Radix-4 Decimation in Frequency Floating-point CFFT & CIFFT 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 1.0.3 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 floating-point CFFT/CIFFT.
+* @param[in,out] *S points to an instance of the floating-point 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_f32(
+ arm_cfft_radix2_instance_f32 * 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 = (float32_t *) twiddleCoef;
+
+ /* 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;
+ /* Initialise the 1/fftLen Value */
+ S->onebyfftLen = 0.000244140625;
+ 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];
+ /* Initialise the 1/fftLen Value */
+ S->onebyfftLen = 0.00048828125;
+ break;
+
+ case 1024u:
+ /* Initializations of structure parameters for 1024 point FFT */
+
+ /* Initialise the twiddle coef modifier value */
+ S->twidCoefModifier = 4u;
+ /* Initialise the bit reversal table modifier */
+ S->bitRevFactor = 4u;
+ /* Initialise the bit reversal table pointer */
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[3];
+ /* Initialise the 1/fftLen Value */
+ S->onebyfftLen = 0.0009765625f;
+ break;
+
+ case 512u:
+ /* Initializations of structure parameters for 512 point FFT */
+
+ /* Initialise the twiddle coef modifier value */
+ S->twidCoefModifier = 8u;
+ /* Initialise the bit reversal table modifier */
+ S->bitRevFactor = 8u;
+ /* Initialise the bit reversal table pointer */
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[7];
+ /* Initialise the 1/fftLen Value */
+ S->onebyfftLen = 0.001953125;
+ break;
+
+ case 256u:
+ /* Initializations of structure parameters for 256 point FFT */
+ S->twidCoefModifier = 16u;
+ S->bitRevFactor = 16u;
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[15];
+ S->onebyfftLen = 0.00390625f;
+ break;
+
+ case 128u:
+ /* Initializations of structure parameters for 128 point FFT */
+ S->twidCoefModifier = 32u;
+ S->bitRevFactor = 32u;
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[31];
+ S->onebyfftLen = 0.0078125;
+ break;
+
+ case 64u:
+ /* Initializations of structure parameters for 64 point FFT */
+ S->twidCoefModifier = 64u;
+ S->bitRevFactor = 64u;
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[63];
+ S->onebyfftLen = 0.015625f;
+ break;
+
+ case 32u:
+ /* Initializations of structure parameters for 64 point FFT */
+ S->twidCoefModifier = 128u;
+ S->bitRevFactor = 128u;
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[127];
+ S->onebyfftLen = 0.03125;
+ break;
+
+ case 16u:
+ /* Initializations of structure parameters for 16 point FFT */
+ S->twidCoefModifier = 256u;
+ S->bitRevFactor = 256u;
+ S->pBitRevTable = (uint16_t *) & armBitRevTable[255];
+ S->onebyfftLen = 0.0625f;
+ 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
+ */
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