/* Includes ------------------------------------------------------------------*/
#include "stm32f4_discovery.h"

/* Private variables ---------------------------------------------------------*/

/* Private functions ---------------------------------------------------------*/
// write to SPI1
void SPI1_Write(int8_t data)
{
  while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET){}
  SPI_I2S_SendData(SPI1, data);

  while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET){}
  SPI_I2S_ReceiveData(SPI1);
}

// read from SPI1
int8_t SPI1_Read()
{
  while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET){}
  SPI_I2S_SendData(SPI1, 0x00);

  while(SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET){}
  return SPI_I2S_ReceiveData(SPI1);
}

void delay(uint32_t delay) {
  while(delay--);
}

volatile int8_t data[2];

void initSPI1(void)
{
  // RCC
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
  // PA5, PA6, PA7 for MISO, MOSI, and SCLK
  GPIO_InitTypeDef GPIO_InitStructure;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);

  // SPI1 INIT
  SPI_InitTypeDef SPI_InitStruct;
  SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
  SPI_InitStruct.SPI_Mode = SPI_Mode_Master;
  SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b;
  SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low;
  SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge;
  SPI_InitStruct.SPI_NSS = SPI_NSS_Soft;
  SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
  SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;
  SPI_InitStruct.SPI_CRCPolynomial = 7;
  SPI_Init(SPI1, &SPI_InitStruct);

  // SPI1 ENABLE
  SPI_Cmd(SPI1, ENABLE);
}

void initMotionSensor()
{
  // RCC
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
  // PE3 for slave select
  GPIO_InitTypeDef SS;
  SS.GPIO_Pin = GPIO_Pin_3;
  SS.GPIO_Mode = GPIO_Mode_OUT;
  SS.GPIO_OType = GPIO_OType_PP;
  SS.GPIO_PuPd = GPIO_PuPd_NOPULL;
  SS.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_Init(GPIOE, &SS);
  GPIO_SetBits(GPIOE, GPIO_Pin_3);

  // configure and start sensor
  delay(500);
  GPIO_ResetBits(GPIOE, GPIO_Pin_3);
  //Pisanje 0x47 na naslov 0x20
  SPI1_Write(0x20);
  SPI1_Write(0x47);
  GPIO_SetBits(GPIOE, GPIO_Pin_3);
  delay(500);
}

void initUSART1()
{
  // RCC
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
  // USART1 init
  USART_InitTypeDef USART_InitStruct;
  USART_InitStruct.USART_BaudRate = 115200;
  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);
  // USART1 enable
  USART_Cmd(USART1, ENABLE);
  // PB6 and PB7 for USART1 Tx and Rx
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
  GPIO_InitTypeDef GPIO_InitStructure;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  //GPIO pini funkcija
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_USART1);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_USART1);
}

void initDMA2()
{
  // RCC
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
  // init DMA2
  DMA_InitTypeDef DMA_InitStructure;
  DMA_InitStructure.DMA_Channel = DMA_Channel_4;
  DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
  DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t) data; //Sprememba
  DMA_InitStructure.DMA_BufferSize = 2;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) &(USART1->DR); //Sprememba
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
  DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
  //DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
  //DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
  DMA_Init(DMA2_Stream7, &DMA_InitStructure);           //Stream??
  // enable USART1 DMA Tx
  USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);
  // enable DMA2 stream
  DMA_Cmd(DMA2_Stream7, ENABLE);
}

/**
  * @brief   Main program
  * @param  None
  * @retval None
  */
int main(void)
{
  // SPI1
  initSPI1();

  // LIS motion sensor
  initMotionSensor();

  // USART1
  initUSART1();

  // DMA2
  initDMA2();

  while (1)
  {
    // read x
    GPIO_ResetBits(GPIOE, GPIO_Pin_3);
    SPI1_Write(0x29 | 0x80);
    data[0] = SPI1_Read();
    GPIO_SetBits(GPIOE, GPIO_Pin_3);
    delay(500);
    // read y
    GPIO_ResetBits(GPIOE, GPIO_Pin_3);
    SPI1_Write(0x2B | 0x80);
    data[1] = SPI1_Read();
    GPIO_SetBits(GPIOE, GPIO_Pin_3);

  }
}