[参考译文] CCS/TM4C123GH6PM：ARM_FFT_BIM_Example_F32代码：如何实现 bin 到 frequency 的转换？

#include "arm_math.h"

#include "arm_const_structs.h"


#define TEST_LENGTH_SAples 2048


/*--------------------------------------

* FFT Bin 的外部输入和输出缓冲器声明示例

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extern float32_ttestInput_F32_10kHz[test_length_samples]；

静态 float32_tTestOutput[test_length_samples/2]；


/*--------------------------------------

* FFT Bin 示例的全局变量

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uint32_t fftSize = 1024；

uint32_t ifftFlag = 0；

uint32_t doBitReverse = 1；


/*二进制八进制总能量最大值时的参考指数*/

uint32_t refIndex = 213、 testIndex = 0；


/*----------------------------------------------

*最大幅度 FFT Bin 测试

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int32_t main(空)

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ARM_STATUS状态；

float32_t maxValue；


状态= ARM_MATH_SUCCESS；


/*通过 CFFT/CIFFT 模块处理数据*/

ARM_CFFT_F32(&ARM_CFFT_SR_F32_len1024、 testInput_F32_10kHz、 ifftFlag、 doBitReverse)；


/*通过的复数幅度模块处理数据

计算每个区间的幅度*/

arm_cmplx_mag_F32(testInput_F32_10kHz、 TestOutput、 fftSize)；


/*计算 maxValue 并返回相应的 bin 值*/

arm_max_F32(TestOutput、 fftSize、&maxValue、&testIndex)；


if (testIndex ！= refIndex)

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状态= ARM_MATH_TEST_FAILURE；

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/*----------------------------------------------

**如果信号未通过通过通过检查，则在此环路。

**这表示测试失败

**-------------------------------------- *


if (status！= ARM_MATH_SUCCESS)

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while (1)；

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while (1)；/* main 函数不返回*/

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