I2C.c

#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_rcc.h"
#include "delay.h"
#include "stm32f10x_i2c.h"
#include "I2C.h"


//Global structures as handles for peripheral devices:
GPIO_InitTypeDef i2c_gpio;
I2C_InitTypeDef i2c;

void init_I2C1(void)
{
  // Enable the GPIOB, I2C1 and AFIO modules.
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
  
  // Setup the I2C BUS properties through the defined "i2c" structure:
  i2c.I2C_ClockSpeed = 100000;    //Bus clock speed 100kbps
  i2c.I2C_Mode = I2C_Mode_I2C;
  i2c.I2C_DutyCycle = I2C_DutyCycle_2;
  // Setup I2C BUS master properties:
  i2c.I2C_OwnAddress1 = 0x15;
  i2c.I2C_Ack = I2C_Ack_Enable;
  i2c.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
  // Finally initialize the I2C1 unit using the "i2c" structure.
  I2C_Init(I2C1, &i2c);
  
  // Configure the GPIO pins shared between the I2C module
  i2c_gpio.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  i2c_gpio.GPIO_Mode = GPIO_Mode_AF_OD;
  i2c_gpio.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOB, &i2c_gpio);
  
  // Enable the I2C1 module:
  I2C_Cmd(I2C1, ENABLE);
}

/*******************************************************************/
void I2C_StartTransmission(I2C_TypeDef* I2Cx, uint8_t transmissionDirection,  uint8_t slaveAddress)
{
  // Wait until I2C module is idle:
  while(I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY));
  
  // Generate the start condition
  I2C_GenerateSTART(I2Cx, ENABLE);
  // 
  while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_MODE_SELECT));
  
  //Send the address of the slave to be contacted:
  I2C_Send7bitAddress(I2Cx, slaveAddress<<1, transmissionDirection);
  
  //If this is a write operation, set I2C for transmit
  if(transmissionDirection== I2C_Direction_Transmitter)
    {
      while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
    }
  //Or if a read operation, set i2C for receive
  if(transmissionDirection== I2C_Direction_Receiver)
    {
      while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
    }
}

/*******************************************************************/
void I2C_WriteData(I2C_TypeDef* I2Cx, uint8_t data)
{
  // Write the data on the bus
  I2C_SendData(I2Cx, data);
  //Wait until transmission is complete:
  while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
}



/*******************************************************************/
uint8_t I2C_ReadData(I2C_TypeDef* I2Cx)
{
  // Wait until receive is completed
  while( !I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED) );
  uint8_t data;
  // Read one byte of data from I2c
  data = I2C_ReceiveData(I2Cx);
  return data;
}