File content as of revision 3:cd1cb0003a3d:

// Author: Stefano Fasciani - stefanofasciani@stefanofasciani.com
// Date 7/8/2016
// FM Sinth for DISCO_F746NG and ADXL345

#include "sinth.h"

float table[TABLE_SIZE];
int16_t out_buffer[AUDIO_BLOCK_SIZE*2];
float osc_buf[AUDIO_BLOCK_SIZE/2];
__IO uint32_t  audio_out_buffer_state = BUFFER_OFFSET_NONE;
float idx_1 = 0;
float idx_2 = 0;
float filt_old_samp = 0;
static float frqTL = 0.04266666666667;
static float two_pi_48k = 1.3089969389957471826927680763665e-4;
int acc_readings[3];
int update_round = 0;

void BSP_AUDIO_OUT_TransferComplete_CallBack(void){
  audio_out_buffer_state = BUFFER_OFFSET_FULL;
  return;
}


void BSP_AUDIO_OUT_HalfTransfer_CallBack(void){
  audio_out_buffer_state = BUFFER_OFFSET_HALF;
  return;
}

uint8_t SetSysClock_PLL_HSE_200MHz()
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_OscInitTypeDef RCC_OscInitStruct;

  // Enable power clock  
  __PWR_CLK_ENABLE();
  
  // Enable HSE oscillator and activate PLL with HSE as source
  RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState            = RCC_HSE_ON; /* External xtal on OSC_IN/OSC_OUT */

  // Warning: this configuration is for a 25 MHz xtal clock only
  RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource       = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM            = 25;            // VCO input clock = 1 MHz (25 MHz / 25)
  RCC_OscInitStruct.PLL.PLLN            = 400;           // VCO output clock = 400 MHz (1 MHz * 400)
  RCC_OscInitStruct.PLL.PLLP            = RCC_PLLP_DIV2; // PLLCLK = 200 MHz (400 MHz / 2)
  RCC_OscInitStruct.PLL.PLLQ            = 8;             // USB clock = 50 MHz (400 MHz / 8)
  
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    return 0; // FAIL
  }

  // Activate the OverDrive to reach the 216 MHz Frequency
  if (HAL_PWREx_EnableOverDrive() != HAL_OK)
  {
    return 0; // FAIL
  }
  
  // Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers
  RCC_ClkInitStruct.ClockType      = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
  RCC_ClkInitStruct.SYSCLKSource   = RCC_SYSCLKSOURCE_PLLCLK; // 200 MHz
  RCC_ClkInitStruct.AHBCLKDivider  = RCC_SYSCLK_DIV1;         // 200 MHz
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;           //  50 MHz
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;           // 100 MHz
  
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_7) != HAL_OK)
  {
    return 0; // FAIL
  }
  HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSE, RCC_MCODIV_4);
  return 1; // OK
}

void sint_osc(){
    
    int i;
    float mod;
    int indexBase;
    float indexFract, value1, value2;
    
    for (i=0;i<AUDIO_BLOCK_SIZE/2;i++){
        indexBase = floor(idx_2);
        indexFract = idx_2 - (float)indexBase;
        value1 = table[indexBase];
        value2 = table[(indexBase+1)%TABLE_SIZE];
        mod = moddepth*(value1 + ((value2 - value1) * indexFract));
        
        indexBase = floor(idx_1);
        indexFract = idx_1 - (float)indexBase;
        value1 = table[indexBase];
        value2 = table[(indexBase+1)%TABLE_SIZE];
        osc_buf[i] = amplitude*(value1 + ((value2 - value1) * indexFract)); 

        idx_1 = idx_1 + ((frqTL * pitch) + mod);
        while (idx_1 >= TABLE_SIZE){
            idx_1 -= TABLE_SIZE;
        }
        while (idx_1 < 0){
            idx_1 += TABLE_SIZE;
        }
        idx_2 = idx_2 + (frqTL * modrate);
        while (idx_2 >= TABLE_SIZE){
            idx_2 -= TABLE_SIZE;
        }
        while (idx_2 < 0){
            idx_2 += TABLE_SIZE;
        }
        
    }
    
    osc_buf[0] = filter*osc_buf[0] + (1-filter)*filt_old_samp;
    for(i=1;i<AUDIO_BLOCK_SIZE/2;i++){
        osc_buf[i] = filter*osc_buf[i] + (1-filter)*osc_buf[i-1];
    }
    filt_old_samp = osc_buf[(AUDIO_BLOCK_SIZE/2)-1];
    
    
    return;
}

void copy_buffer(int offset){
    int i;
    for(i=0;i<AUDIO_BLOCK_SIZE/2;i++){
            out_buffer[offset+(i*2)] = out_buffer[offset+(i*2)+1] = (int16_t)(30000*osc_buf[i]);
    }
    
    return;
}


void init_sin_table(){
    
    int i;
    for(i=0;i<TABLE_SIZE;i++){
        table[i] = sinf((float)(two_pi_48k*(23.4375f)*(float)i));
    }    
    return;    
}

float map_full(float x, float in_min, float in_max, float out_min, float out_max) {
  return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}

float map(float x, float out_min, float out_max) {
  return (x - 0.0f) * (out_max - out_min) / (1.0f - 0.0f) + out_min;
}

float get_touch_horizontal(){
    float temp = map_full(TS.touchX[0],1,480,0.0,1.0);
    if(temp > 1)temp=1;
    else if(temp < 0)temp=0;
    return temp;
}

float get_touch_vertical(){
    float temp = map_full(TS.touchY[0],1,272,0.0,1.0);     
    if(temp > 1)temp=1;
    else if(temp < 0)temp=0;
    return temp;
}

float get_acc_horizontal(){
    float temp = map_full((float)(int16_t)acc_readings[1],230,-230,0.0,1.0); //for full range -/+256
    if(temp > 1)temp=1;
    else if(temp < 0)temp=0;
    return temp;
}

float get_acc_vertical(){
    float temp = map_full((float)(int16_t)acc_readings[0],230,-230,0.0,1.0); //for full range -/+256
    if(temp > 1)temp=1;
    else if(temp < 0)temp=0;
    return temp;
}

void display_keyboard(){
      
      lcd.SetTextColor(LCD_COLOR_LIGHTRED);
      lcd.FillRect(2,0,38,272);
      lcd.FillRect(82,0,38,272);  
      lcd.FillRect(162,0,38,272);  
      lcd.FillRect(202,0,38,272);
      lcd.FillRect(282,0,38,272);
      lcd.FillRect(362,0,38,272);
      lcd.FillRect(442,0,38,272);
      
      lcd.SetTextColor(LCD_COLOR_DARKRED);
      lcd.FillRect(42,0,38,272);
      lcd.FillRect(122,0,38,272);
      lcd.FillRect(242,0,38,272);
      lcd.FillRect(322,0,38,272);
      lcd.FillRect(402,0,38,272);
      
      lcd.SetTextColor(LCD_COLOR_BLACK);
      lcd.FillRect(1,21,480,232);
      
      return;
}

float get_note_pitch(){
    
    float pitch = 0;
    
    if((TS.touchX[0]>=1)&&(TS.touchX[0]<=40)) pitch = 523.25f;
    else if((TS.touchX[0]>=41)&&(TS.touchX[0]<=80)) pitch = 554.37f;
    else if((TS.touchX[0]>=81)&&(TS.touchX[0]<=120)) pitch = 587.33f;
    else if((TS.touchX[0]>=121)&&(TS.touchX[0]<=160)) pitch = 622.25f;
    else if((TS.touchX[0]>=161)&&(TS.touchX[0]<=200)) pitch = 659.25f;
    else if((TS.touchX[0]>=201)&&(TS.touchX[0]<=240)) pitch = 698.46f;
    else if((TS.touchX[0]>=241)&&(TS.touchX[0]<=280)) pitch = 739.99f;
    else if((TS.touchX[0]>=281)&&(TS.touchX[0]<=320)) pitch = 783.99f;
    else if((TS.touchX[0]>=321)&&(TS.touchX[0]<=360)) pitch = 830.61f;
    else if((TS.touchX[0]>=361)&&(TS.touchX[0]<=400)) pitch = 880.00;
    else if((TS.touchX[0]>=401)&&(TS.touchX[0]<=440)) pitch = 932.33;
    else if((TS.touchX[0]>=441)&&(TS.touchX[0]<=480)) pitch = 987.77;
    
    return pitch;    
}