#include "stm32f4xx_rcc.c"
#include "stm32f4xx_gpio.c"
#include "stm32f4xx_tim.c"
#include "stm32f4xx_spi.c"

#include "LCD2x16.c" 
#include "dd.h"

void GPIOBinit_SPI2(void)   {
GPIO_InitTypeDef          GPIO_InitStructure;
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE); 

  GPIOB->BSRRL = BIT_14 | BIT_13 | BIT_12 | BIT_11;
  
  GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; 
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_25MHz;
  GPIO_Init(GPIOB, &GPIO_InitStructure);   

  GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_11 | GPIO_Pin_12; // PB12, PB12: SPI_SEL
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_OUT;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; 
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_25MHz;
  GPIO_Init(GPIOB, &GPIO_InitStructure);   

  GPIO_PinAFConfig(GPIOB, GPIO_PinSource13, GPIO_AF_SPI2);  // PB13:SPI2_SCK
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource14, GPIO_AF_SPI2);  // PB14:SPI2_MISO
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource15, GPIO_AF_SPI2);  // PB15:SPI2_MOSI
}

void SPI2init(void) {       // 
SPI_InitTypeDef   SPI_InitStructure;
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2,  ENABLE);
  GPIOBinit_SPI2();     // GPIO clock enable, digital pin definitions
  
  SPI_InitStructure.SPI_Direction       = SPI_Direction_2Lines_FullDuplex ;
  SPI_InitStructure.SPI_Mode            = SPI_Mode_Master;
  SPI_InitStructure.SPI_DataSize        = SPI_DataSize_16b;
  SPI_InitStructure.SPI_CPOL            = SPI_CPOL_High;
  SPI_InitStructure.SPI_CPHA            = SPI_CPHA_2Edge;
  SPI_InitStructure.SPI_NSS             = SPI_NSS_Soft;
  SPI_InitStructure.SPI_BaudRatePrescaler       = SPI_BaudRatePrescaler_64;
  SPI_InitStructure.SPI_FirstBit        = SPI_FirstBit_MSB;
  SPI_InitStructure.SPI_CRCPolynomial   = 7;
  SPI_Init(SPI2, &SPI_InitStructure);
  
  SPI_Cmd(SPI2, ENABLE);
}

void LIS_write (char address, char data)        {
  GPIOB->BSRRH = BIT_12;
  for (int i = 0; i < 150; i++)   {};           // waste time
  SPI2->DR = ((unsigned short)(address & 0x3f) << 8) + (unsigned short)(data);  
  for (int i = 0; i < 1200; i++)  {};           // waste time
  GPIOB->BSRRL = BIT_12;
}

short LIS_read (char address) {
  GPIOB->BSRRH = BIT_12;
  for (int i = 0; i < 150; i++)   {};           // waste time
  SPI2->DR = ((address & 0x3f) << 8) + 0x8000;  
  for (int i = 0; i < 1200; i++)  {};           // waste time
  GPIOB->BSRRL = BIT_12;
  return (SPI2->DR & 0xff);
}

int main ()  {
//short unsigned ii = 0;
  SPI2init();                                   // SPI2 init
  LCD_init();                                   // Init LCD
  LCD_string("SPI demo Z", 0);                  // write title
  LCD_string("X        Y", 0x40);               // write title
  
  LIS_write (0x20,0xc7);
  
  // waste time - indefinite
  while (1) {
    short xLSB = LIS_read(0x28); short xMSB = LIS_read(0x29) << 8;
    short yLSB = LIS_read(0x2a); short yMSB = LIS_read(0x2b) << 8;
    short zLSB = LIS_read(0x2c); short zMSB = LIS_read(0x2d) << 8;
    LCD_sInt16((xLSB + xMSB), 0x41, 0x01);      // show acc x
    LCD_sInt16((yLSB + yMSB), 0x4a, 0x01);      // show acc y
    LCD_sInt16((zLSB + zMSB), 0x0a, 0x01);      // show acc z
    for (int i = 0; i < 10000000; i++)   {};    // waste time
  };
}