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

unsigned Tim2Safe = 0;
char Tim2Flag = 0;

void Init_GPIOE (void)  {
GPIO_InitTypeDef GPIO_InitStruct;

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
  GPIO_InitStruct.GPIO_Pin   = GPIO_Pin_8  | GPIO_Pin_9  | GPIO_Pin_10 | GPIO_Pin_11 | 
                         GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;             
  GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_OUT;
  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_25MHz;
  GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStruct.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOE, &GPIO_InitStruct);
}

void Init_TIM3 (void)   {               // master: TIM3 CH4
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
TIM_OCInitTypeDef       TIM_OCInitStruct;
GPIO_InitTypeDef GPIO_InitStruct;
  
  // pripravi PWM OC4 na PB1
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
  GPIO_InitStruct.GPIO_Pin   = GPIO_Pin_1;             
  GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_AF;
  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_25MHz;
  GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStruct.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOB, &GPIO_InitStruct);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource1, GPIO_AF_TIM3); 
  // OK, pripravljeno
  // poženi TIM3
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
  TIM_TimeBaseInitStruct.TIM_Prescaler               = 1999;         
  TIM_TimeBaseInitStruct.TIM_CounterMode             = TIM_CounterMode_Up;       
  TIM_TimeBaseInitStruct.TIM_Period                  = 46199;           // perioda  
  TIM_TimeBaseInitStruct.TIM_ClockDivision           = TIM_CKD_DIV1;     
  TIM_TimeBaseInitStruct.TIM_RepetitionCounter       = 0;  
  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseInitStruct);
  TIM_Cmd(TIM3, ENABLE);
  TIM_InternalClockConfig(TIM3);
  // TIM3 zdaj tece
  // nastavi PWM: OC4
  TIM_OCInitStruct.TIM_OCMode           = TIM_OCMode_PWM1;
  TIM_OCInitStruct.TIM_OutputState      = TIM_OutputState_Enable;
  TIM_OCInitStruct.TIM_OutputNState     = TIM_OutputState_Disable;
  TIM_OCInitStruct.TIM_Pulse            = 42000;                         // interval
  TIM_OCInitStruct.TIM_OCPolarity       = TIM_OCPolarity_Low;
  TIM_OCInitStruct.TIM_OCNPolarity      = TIM_OCPolarity_Low;
  TIM_OCInitStruct.TIM_OCIdleState      = TIM_OCIdleState_Set;
  TIM_OCInitStruct.TIM_OCNIdleState     = TIM_OCIdleState_Set;
  TIM_OC4Init(TIM3, &TIM_OCInitStruct);
   
  TIM_SelectOutputTrigger(TIM3, TIM_TRGOSource_OC4Ref);
  TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable); 
  
  TIM_ITConfig(TIM3, TIM_IT_CC4, ENABLE);
  NVIC_EnableIRQ(TIM3_IRQn);                                             // interrupt at the end of interval
  TIM_ITConfig(TIM3, TIM_IT_CC4, ENABLE);
}

void Init_TIM2 (void)   {               // slave: TIM2
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
GPIO_InitTypeDef GPIO_InitStruct;
  // pripravi ETR na PA15
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
  GPIO_InitStruct.GPIO_Pin   = GPIO_Pin_15;             
  GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_AF;
  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_25MHz;
  GPIO_InitStruct.GPIO_PuPd  = GPIO_PuPd_DOWN;
  GPIO_Init(GPIOA, &GPIO_InitStruct);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource15, GPIO_AF_TIM2);
  // OK, pripravljeno
  // poženi TIM2
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
  TIM_TimeBaseInitStruct.TIM_Prescaler               = 0;         
  TIM_TimeBaseInitStruct.TIM_CounterMode             = TIM_CounterMode_Up;       
  TIM_TimeBaseInitStruct.TIM_Period                  = 0xffffffff;           // perioda  
  TIM_TimeBaseInitStruct.TIM_ClockDivision           = TIM_CKD_DIV1;     
  TIM_TimeBaseInitStruct.TIM_RepetitionCounter       = 0;  
  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStruct);
  
  TIM_SelectInputTrigger(TIM2, TIM_TS_ITR2);            // gate iz TIM3
  TIM_SelectSlaveMode(TIM2, TIM_SlaveMode_Gated);       //
        
  TIM_ETRClockMode2Config(TIM2, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0);          // štejemo iz ETR
  TIM_Cmd(TIM2, ENABLE);
  // TIM2 zdaj tece
}

void main (void)        { 
  LCD_init();
  LCD_string("Frequency[Hz]:", 0x01);
  Init_GPIOE();
  Init_TIM3();
  Init_TIM2();
  while (1) {
    if (Tim2Flag == 1) {
      Tim2Flag = 0;
      LCD_uInt32(Tim2Safe, 0x45, 0x01);
    };
  };
}

// IRQ function for Timer3
void TIM3_IRQHandler(void)       {
  GPIOE->ODR |=  BIT_8;
  TIM_ClearITPendingBit(TIM3, TIM_IT_CC4); // clear interrupt flag
  Tim2Safe = TIM2->CNT;
  Tim2Flag = 1;
  TIM2->CNT = 0;
  GPIOE->ODR &= ~BIT_8;        
}