/* Includes ------------------------------------------------------------------*/
#include "stm32f4_discovery.h"
#include "stm32f4xx_usart.h"
volatile uint16_t calc = (uint16_t)1;
void DELAY(){
  uint32_t d = 0x01000000;
  while(d--);
}
void EXTI0_IRQHandler(){
  if (EXTI_GetITStatus(EXTI_Line0)){
    while(!USART_GetFlagStatus(USART1, USART_FLAG_TXE));
    USART_SendData(USART1, calc);
    EXTI_ClearITPendingBit(EXTI_Line0);
  }
  calc++;
  if(calc>153) calc = 0;
}
volatile uint16_t data = (uint16_t)0x0;
void USART1_IQRHandler(){
    if(USART_GetITStatus(USART1, USART_FLAG_RXNE)){
    data=USART_ReceiveData(USART1);
    if(data){
          GPIO_SetBits(GPIOD,0xF000);
          DELAY();
          GPIO_ResetBits(GPIOD, 0xF000);
          DELAY();
    }
    data = (uint16_t)0x0;
    }
    USART_ClearFlag(USART1, USART_FLAG_RXNE);
}
int main(void){
  //Start the device(= pins) clock
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
  //Init the Device Structure
  GPIO_InitTypeDef u1;
  u1.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  u1.GPIO_Mode = GPIO_Mode_AF;
  u1.GPIO_Speed = GPIO_Speed_2MHz;
  u1.GPIO_OType = GPIO_OType_PP;
  u1.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_Init(GPIOB, &u1);
  //Alternative function pins setup
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource6,GPIO_AF_USART1);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource7,GPIO_AF_USART1);
  //Usart Setup
  //Start the device(=usart1)
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
  USART_InitTypeDef USART_InitStruct;
  USART_InitStruct.USART_BaudRate = 9600;
  USART_InitStruct.USART_WordLength = USART_WordLength_8b;
  USART_InitStruct.USART_StopBits = USART_StopBits_1;
  USART_InitStruct.USART_Parity = USART_Parity_No;
  USART_InitStruct.USART_HardwareFlowControl =
  USART_HardwareFlowControl_None;
  USART_InitStruct.USART_Mode = USART_Mode_Tx |
  USART_Mode_Rx;
  USART_Init(USART1, &USART_InitStruct);
  USART_Cmd(USART1, ENABLE);

  //Start the device(=leds) clock
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
  //Init the Device Structure
  GPIO_InitTypeDef leds;
  leds.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
  leds.GPIO_Mode = GPIO_Mode_OUT;
  leds.GPIO_Speed = GPIO_Speed_2MHz;
  leds.GPIO_OType = GPIO_OType_PP;
  leds.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOD, &leds);
   //Start the device(= button) clock
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
  //Init the device(=button) structure
  GPIO_InitTypeDef button;
  button.GPIO_Pin = GPIO_Pin_0;
  button.GPIO_Mode = GPIO_Mode_IN;
  button.GPIO_Speed = GPIO_Speed_2MHz;
  button.GPIO_OType = GPIO_OType_PP;
  button.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOD, &button);
   //Interupt for button
  NVIC_InitTypeDef NVIC_InitStructure;
  NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
  //Exception handler for button
  EXTI_InitTypeDef EXTI_InitStructure;
  EXTI_InitStructure.EXTI_Line = EXTI_Line0;
  EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
  EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
  EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  EXTI_Init(&EXTI_InitStructure);
  //Interrupt for USART
  NVIC_InitTypeDef NVIC_InitStructure2;
  NVIC_InitStructure2.NVIC_IRQChannel = USART1_IRQn;
  NVIC_InitStructure2.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure2.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure2.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure2);
  USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
  //Start
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
  SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource0);
  while (1){

  }
}