#include "stm32f4xx.h"
#include "stm32f4xx_rcc.c"
#include "stm32f4xx_adc.c"
#include "stm32f4xx_dac.c"
#include "stm32f4xx_gpio.c"
#include "stm32f4xx_tim.c"
#include "dd.h"
#include "LCD2x16.c"
#include "math.h"

short int X[64], k = 0;
float Y0[64], Y90[64];
float Y0F[64], Y90F[64];
float Y1[64], Y2[64], Y3[64];
int Table[4096], ptrTable;   
float R_phi, R_amp, R_phi_acc, R_amp_acc, R_phi_fin, R_amp_fin;
float R_im, R_re, R_im_acc, R_re_acc, R_im_fin, R_re_fin;

// ADC init function
void ADCinit_T5_CC1_IRQ (void)      {
ADC_InitTypeDef         ADC_InitStructure;
GPIO_InitTypeDef        GPIO_InitStructure;
ADC_CommonInitTypeDef   ADC_CommonInitStructure;
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1  | RCC_APB2Periph_ADC2,  ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB, ENABLE);
  
  GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_1 | GPIO_Pin_2;
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AN;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOA, &GPIO_InitStructure); 
  
  ADC_CommonInitStructure.ADC_DMAAccessMode    = ADC_DMAAccessMode_Disabled;
  ADC_CommonInitStructure.ADC_Mode             = ADC_DualMode_RegSimult;
  ADC_CommonInitStructure.ADC_Prescaler        = ADC_Prescaler_Div2;
  ADC_CommonInit(&ADC_CommonInitStructure);
    
  ADC_InitStructure.ADC_Resolution             = ADC_Resolution_12b;
  ADC_InitStructure.ADC_ScanConvMode           = DISABLE;
  ADC_InitStructure.ADC_ContinuousConvMode     = DISABLE;
  ADC_InitStructure.ADC_ExternalTrigConvEdge   = ADC_ExternalTrigConvEdge_Rising;
  ADC_InitStructure.ADC_ExternalTrigConv       = ADC_ExternalTrigConv_T5_CC1;
  ADC_InitStructure.ADC_DataAlign              = ADC_DataAlign_Right;
  ADC_InitStructure.ADC_NbrOfConversion        = 1;
  ADC_Init(ADC1, &ADC_InitStructure);
  ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_3Cycles);

  ADC_Init(ADC2, &ADC_InitStructure);
  ADC_RegularChannelConfig(ADC2, ADC_Channel_2, 1, ADC_SampleTime_3Cycles);

  ADC_Cmd(ADC1, ENABLE);
  ADC_Cmd(ADC2, ENABLE);

  NVIC_EnableIRQ(ADC_IRQn);                // Enable IRQ for ADC in NVIC 
  ADC_ITConfig(ADC1, ADC_IT_EOC, ENABLE);  // Enable IRQ generation in ADC 
}

// DAC init function
void DACinit (void)     {
DAC_InitTypeDef         DAC_InitStructure;
GPIO_InitTypeDef        GPIO_InitStructure;
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
  GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_4 | GPIO_Pin_5;
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AN;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;  
  GPIO_Init(GPIOA, &GPIO_InitStructure);  
  
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
  DAC_InitStructure.DAC_OutputBuffer                 = DAC_OutputBuffer_Enable;
  DAC_InitStructure.DAC_Trigger                      = DAC_Trigger_None;
  DAC_InitStructure.DAC_WaveGeneration               = DAC_WaveGeneration_None;
  DAC_Init(DAC_Channel_1, &DAC_InitStructure); 
  DAC_Init(DAC_Channel_2, &DAC_InitStructure);
  
  DAC_Cmd(DAC_Channel_1, ENABLE);   
  DAC_Cmd(DAC_Channel_2, ENABLE);
}

// Timer 5 init function - time base
void TIM5init_TimeBase_CC1 (int interval)  {
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
TIM_OCInitTypeDef       TIM_OCInitStructure;
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5,  ENABLE);
  TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInitStructure.TIM_Period = interval; 
  TIM_TimeBaseInitStructure.TIM_Prescaler = 0;
  TIM_TimeBaseInitStructure.TIM_RepetitionCounter = 0;
  TIM_TimeBaseInit(TIM5, &TIM_TimeBaseInitStructure);

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_OutputNState = TIM_OutputState_Disable;
  TIM_OCInitStructure.TIM_Pulse = 1;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
  TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_Low;
  TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
  TIM_OCInitStructure.TIM_OCNIdleState =  TIM_OCIdleState_Set;
  TIM_OC1Init(TIM5, &TIM_OCInitStructure);

  TIM_Cmd(TIM5, ENABLE);
}   

// initialize port E, Gpio_Pin_8 to GPIO_Pin_15 as outputs
void GPIOEinit (void)   {
GPIO_InitTypeDef  GPIO_InitStructure;
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
  GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_8  | GPIO_Pin_9  | GPIO_Pin_10 | GPIO_Pin_11;
  GPIO_InitStructure.GPIO_Pin  |= GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_OUT;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOE, &GPIO_InitStructure); 
}

#define pi 3.14159
int main ()  {                  
int del;
  for (ptrTable = 0; ptrTable <= 4095; ptrTable++)
    Table[ptrTable] = (int)(1850.0 * sin((float)ptrTable / 2048.0 * 3.14159265));

  LCD_init (); 
  LCD_string("Pha=          dg", 0x00);
  LCD_string("Amp=          mV", 0x40); 

  GPIOEinit ();
  ADCinit_T5_CC1_IRQ();
  DACinit();
  TIM5init_TimeBase_CC1(840);           // 840 == 10 us == 100 kHz

  while (1) {                            // endless loop
    for (del = 0; del < 10000000; del++)  {};
    float Phi_fin = (atan(R_im_fin/R_re_fin)) * 180 / 3.14159;
    if (Phi_fin < 0)    {LCD_string("-", 0x06);    Phi_fin = -Phi_fin; }
    else                {LCD_string(" ", 0x06);                        };
    short Phi_int = (int)Phi_fin;
    short Phi_frc = (int)((Phi_fin - Phi_int) * 10);
    LCD_sInt3DG((int)Phi_int , 0x07, 1);
    LCD_char('.');   LCD_char(Phi_frc + '0');
    float Amp_fin = (sqrt(R_im_fin * R_im_fin + R_re_fin * R_re_fin))/128*.838;
    LCD_sInt16((int)(Amp_fin/256), 0x47, 1);
  };
}

// IRQ function for ADC
void ADC_IRQHandler(void)       
{
  GPIOE->BSRRL = BIT_8;              // signal start, about 4us!

  // DDS generator
  ptrTable = (ptrTable + 655) & 0xffff;         // 655 ==> 1 kHz
  DAC->DHR12R1 = Table[ptrTable >> 4] + 2048;   // next excitation
  
  // Measurement
  X[k] = ADC1->DR;                              
  X[k] = ADC2->DR;                              
  
  // multiply with sin and cos components
  Y0[k]  = (float)X[k] * Table[((ptrTable >> 4) +    0)       ];  
  Y90[k] = (float)X[k] * Table[((ptrTable >> 4) + 1024) & 4095];  
  
  // LP, 1st order filter, corner at about (f sampling / 8000) 
  Y0F[k]  = 0.99999 * Y0F [(k - 1) & 63] + 0.00001 * Y0 [k];   
  Y90F[k] = 0.99999 * Y90F[(k - 1) & 63] + 0.00001 * Y90[k];   

  // some averaging to get smoother result
  R_im_acc += Y90F[k];          
  R_re_acc += Y0F[k];           
  
  // report result every 64th time
  if (k == 0) {                 
    R_im_fin = R_im_acc;        R_im_acc = 0;
    R_re_fin = R_re_acc;        R_re_acc = 0;      
  };
  
  k++; k &= 63;
  GPIOE->BSRRH = BIT_8;                 // signal end
}