DSP-FFT and binning for FPB-Ra0E1

#include "hal_data.h"

#include <../ra/arm/CMSIS-DSP/include/dsp/transform_functions.h>



FSP_CPP_HEADER

void R_BSP_WarmStart(bsp_warm_start_event_t event);

FSP_CPP_FOOTER



/*******************************************************************************************************************//**

* main() is generated by the RA Configuration editor and is used to generate threads if an RTOS is used. This function

* is called by main() when no RTOS is used.

**********************************************************************************************************************/

void hal_entry(void)

{

/* TODO: add your own code here */



/*

* CMSIS FFT

*/

#define SAMPLE_BUFFER_LENGTH 4096

#define SAMPLE_BUFFER_LENGTH_HALF (SAMPLE_BUFFER_LENGTH/2)

#define SAMPLING_RATE 48000



float32_t fft_input[SAMPLE_BUFFER_LENGTH];

float32_t fft_output[SAMPLE_BUFFER_LENGTH];

float32_t fft_power[SAMPLE_BUFFER_LENGTH_HALF];



uint8_t ifftFlag = 0;

float frequency_resolution = (float)SAMPLING_RATE / (float)SAMPLE_BUFFER_LENGTH;




/* write signal to array */

for (int i = 0; i < SAMPLE_BUFFER_LENGTH; i++) {

float32_t r = (float32_t)i/ (float32_t)SAMPLING_RATE;

r *= 3.14159265359 * 2;

r *= 880; // frequency in Hz

float s = sin(r) + sin(r * 4) * 0.5 + sin(r * 3) * 0.25;

fft_input = s;

}



/* analyze signal */

arm_rfft_fast_instance_f32 fft;

arm_rfft_fast_init_f32(&fft, (uint16_t)SAMPLE_BUFFER_LENGTH);

arm_rfft_fast_f32(&fft, fft_input, fft_output, ifftFlag);

arm_cmplx_mag_f32(fft_output, fft_power, (uint32_t)SAMPLE_BUFFER_LENGTH_HALF);

for (int i = 1; i < SAMPLE_BUFFER_LENGTH_HALF; i++) {

//Serial.printf("%i\tfrq: %.1f\tenergy %.6f\r\n", i, i * frequency_resolution, fft_power);

// APP_PRINT("\r\n %i\tfrq: %.1f\tenergy %.6f \r\n", i, i * frequency_resolution, fft_power);

}



/* find dominant frequency */

float32_t maxValue;

uint32_t maxIndex;

arm_max_f32(fft_power, SAMPLE_BUFFER_LENGTH_HALF, &maxValue, &maxIndex);

// Serial.printf("\r\n");

// Serial.printf("max power: %f\r\n", maxValue);

// Serial.printf("max index: %i\r\n", maxIndex);

// Serial.printf("frequency: %f\r\n", (maxIndex * frequency_resolution));

// APP_PRINT("\r\n max power: %f\r\n", maxValue);

// APP_PRINT("\r\n max index: %i\r\n", maxIndex);

// APP_PRINT("\r\n frequency: %f\r\n", (maxIndex * frequency_resolution));




#if BSP_TZ_SECURE_BUILD

/* Enter non-secure code */

R_BSP_NonSecureEnter();

#endif

}



/*******************************************************************************************************************//**

* This function is called at various points during the startup process. This implementation uses the event that is

* called right before main() to set up the pins.

*

* [USER=120004]@Param[/USER][in] event Where at in the start up process the code is currently at

**********************************************************************************************************************/

void R_BSP_WarmStart(bsp_warm_start_event_t event)

{

if (BSP_WARM_START_RESET == event)

{

#if BSP_FEATURE_FLASH_LP_VERSION != 0



/* Enable reading from data flash. */

R_FACI_LP->DFLCTL = 1U;



/* Would normally have to wait tDSTOP(6us) for data flash recovery. Placing the enable here, before clock and

* C runtime initialization, should negate the need for a delay since the initialization will typically take more than 6us. */

#endif

}



if (BSP_WARM_START_POST_C == event)

{

/* C runtime environment and system clocks are setup. */



/* Configure pins. */

R_IOPORT_Open (&IOPORT_CFG_CTRL, &IOPORT_CFG_NAME);



#if BSP_CFG_SDRAM_ENABLED



/* Setup SDRAM and initialize it. Must configure pins first. */

R_BSP_SdramInit(true);

#endif

}

}