75x_i2c.c

嵌入式实验源码。包括：电源管理、复位、时钟管理

/******************** (C) COPYRIGHT 2006 STMicroelectronics ********************
* File Name          : 75x_i2c.c
* Author             : MCD Application Team
* Date First Issued  : 03/10/2006 : V0.1 
* Description        : This file provides all the I2C software functions.
********************************************************************************
* History:
* 03/10/2006 : V0.1 
********************************************************************************
* THE PRESENT SOFTWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT, 
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING 
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
*******************************************************************************/

/* Includes ------------------------------------------------------------------*/
#include "75x_i2c.h"
#include "75x_mrcc.h"

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/

/* I2C IT enable */
#define  I2C_IT_Enable     0x01
#define  I2C_IT_Disable    0xFE

/* I2C Peripheral Enable/Disable */
#define  I2C_PE_Set        0x20
#define  I2C_PE_Reset      0xDF

/* I2C START Enable/Disable */
#define  I2C_Start_Enable      0x08
#define  I2C_Start_Disable     0xF7

/* I2C STOP Enable/Disable */
#define  I2C_Stop_Enable       0x02
#define  I2C_Stop_Disable      0xFD

/* Address direction bit */
#define I2C_ADD0_Set      0x01
#define I2C_ADD0_Reset    0xFE

/* I2C Masks */
#define  I2C_Frequency_Mask     0x1F
#define  I2C_AddressHigh_Mask   0xF9
#define  I2C_OwnAddress_Mask    0x0300  
#define  I2C_StandardMode_Mask  0x7f 
#define  I2C_FastMode_Mask      0x80  
#define  I2C_Event_Mask         0x3FFF

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/*******************************************************************************
* Function Name  : I2C_DeInit                                                
* Description    : Deinitializes the I2C peripheral registers to their default
*                  reset values.                 
* Input          : None               
* Output         : None                                                      
* Return         : None                                                      
*******************************************************************************/
void I2C_DeInit(void)
{
  /* Reset the I2C registers values*/
  MRCC_PeripheralSWResetConfig(MRCC_Peripheral_I2C,ENABLE);
  MRCC_PeripheralSWResetConfig(MRCC_Peripheral_I2C,DISABLE); 
}

/*******************************************************************************
* Function Name  : I2C_Init                                                  
* Description    : Initializes the I2C peripheral according to the specified
*                  parameters in the I2C_Initstruct.
* Input          : - I2C_InitStruct: pointer to a I2C_InitTypeDef structure that
*                  contains the configuration information for the specified I2C
*                  peripheral.               
* Output         : None                                                      
* Return         : None                                                      
*******************************************************************************/
void I2C_Init(I2C_InitTypeDef* I2C_InitStruct)
{
  u8 ITEState = 0;
  u16 Result = 0x0F;
  u32 APBClock = 8000000;
  MRCC_ClocksTypeDef  MRCC_ClocksStatus;

  /* Get APBClock frequency value */
  MRCC_GetClocksStatus(&MRCC_ClocksStatus);
  APBClock = MRCC_ClocksStatus.PCLK_Frequency;
  /* Save ITE bit state */
  ITEState = I2C->CR & 0xFE;
  /* Disable I2C peripheral to set FR[2:0] bits */
  I2C_Cmd(DISABLE);
  /* Clear frequency FR[2:0] bits */
  I2C->OAR2 &= I2C_Frequency_Mask;
  
  /* Set frequency bits depending on APBClock value */
  if (APBClock < 10000000)
    I2C->OAR2 &= 0x1F;
  else if (APBClock < 16670000)
    I2C->OAR2 |= 0x20;
  else if (APBClock < 26670000)
    I2C->OAR2 |= 0x40;
  else if (APBClock < 40000000)
    I2C->OAR2 |= 0x60;
  else if (APBClock < 53330000)
    I2C->OAR2 |= 0x80;
  else if (APBClock < 66000000)
    I2C->OAR2 |= 0xA0;
  else if (APBClock < 80000000)
    I2C->OAR2 |= 0xC0;
  else if (APBClock < 100000000)
    I2C->OAR2 |= 0xE0;
  I2C_Cmd(ENABLE);
  
  /* Restore the ITE bit state */
  I2C->CR |= ITEState;

  /* Configure general call */
  if (I2C_InitStruct->I2C_GeneralCall == I2C_GeneralCall_Enable)
  {
    /* Enable general call */
    I2C->CR |= I2C_GeneralCall_Enable;
  }
  else
  {
    /* Disable general call */
    I2C->CR &= I2C_GeneralCall_Disable;
  }
  
  /* Configure acknowledgement */
  if (I2C_InitStruct->I2C_Ack == I2C_Ack_Enable)
  {
    /* Enable acknowledgement */
    I2C->CR |= I2C_Ack_Enable;
  }
  else
  {
    /* Disable acknowledgement */
    I2C->CR &= I2C_Ack_Disable;
  }
  
  /* Configure LSB own address */
  I2C->OAR1 = I2C_InitStruct->I2C_OwnAddress;
  /* Clear MSB own address ADD[9:8] bits */
  I2C->OAR2 &= I2C_AddressHigh_Mask;
  /* Set MSB own address value */
  I2C->OAR2 |= (I2C_InitStruct->I2C_OwnAddress & I2C_OwnAddress_Mask)>>7;

  /* Configure speed in standard mode */
  if (I2C_InitStruct->I2C_CLKSpeed <= 100000)
  {
    /* Standard mode speed calculate */
    Result = ((APBClock/I2C_InitStruct->I2C_CLKSpeed)-7)/2;
    /* Set speed value and clear FM/SM bit for standard mode in LSB clock divider */
    I2C->CCR = Result & I2C_StandardMode_Mask;
  }
  /* Configure speed in fast mode */
  else if (I2C_InitStruct->I2C_CLKSpeed <= 400000)
  {
    /* Fast mode speed calculate */
    Result = ((APBClock/I2C_InitStruct->I2C_CLKSpeed)-9)/3;
    /* Set speed value and set FM/SM bit for fast mode in LSB clock divider */
    I2C->CCR = Result | I2C_FastMode_Mask;
  }
  /* Set speed in MSB clock divider */
  I2C->ECCR = Result >>7;
}

/*******************************************************************************
* Function Name  : I2C_StructInit                   
* Description    : Fills each I2C_InitStruct member with its default value.
* Input          : - I2C_InitStruct: pointer to an I2C_InitTypeDef structure
                     which will be initialized.  
* Output         : None              
* Return         : None.                            
*******************************************************************************/
void I2C_StructInit(I2C_InitTypeDef* I2C_InitStruct)
{
  /* Initialize the I2C_CLKSpeed member */
  I2C_InitStruct->I2C_CLKSpeed = 5000;
  
  /* Initialize the I2C_OwnAddress member */
  I2C_InitStruct->I2C_OwnAddress = 0x0;
  
  /* Initialize the I2C_GeneralCall member */
  I2C_InitStruct->I2C_GeneralCall = I2C_GeneralCall_Disable;
  
  /* Initialize the I2C_Ack member */
  I2C_InitStruct->I2C_Ack = I2C_Ack_Disable;
}

/*******************************************************************************
* Function Name  : I2C_Cmd                                                    
* Description    : Enables or disables the I2C peripheral.      
* Input          : - NewState: new state of the I2C peripheral. This parameter
*                    can be: ENABLE or DISABLE.
* Output         : None                      
* Return         : None.                                                      
*******************************************************************************/
void I2C_Cmd(FunctionalState NewState)
{
  if (NewState == ENABLE)
  {
    /* Enable the I2C peripheral by setting twice the PE bit on the CR register */
    I2C->CR |= I2C_PE_Set;
    I2C->CR |= I2C_PE_Set;
  }
  else
  {
    /* Disable the I2C peripheral */
    I2C->CR &= I2C_PE_Reset;
  }
}

/*******************************************************************************
* Function Name  : I2C_GenerateSTART                                          
* Description    : Generates I2C communication START condition.               
* Input          : - NewState: new state of the I2C START condition generation.
*                    This parameter can be: ENABLE or DISABLE.         
* Output         : None
* Return         : None.                                                      
*******************************************************************************/
void I2C_GenerateSTART(FunctionalState NewState)
{
  if (NewState == ENABLE)
  {
    /* Generate a START condition */
    I2C->CR |= I2C_Start_Enable;
  }
  else
  {
    /* Disable the START condition generation */
    I2C->CR &= I2C_Start_Disable;
  }
}

/*******************************************************************************
* Function Name  : I2C_GenerateSTOP                                           
* Description    : Generates I2C communication STOP condition.                
* Input          : - NewState: new state of the I2C STOP condition generation.
*                    This parameter can be: ENABLE or DISABLE.       
* Output         : None                
* Return         : None.                                                      
*******************************************************************************/
void I2C_GenerateSTOP(FunctionalState NewState)
{
  if (NewState == ENABLE)
  {
    /* Generate a SIOP condition */
    I2C->CR |= I2C_Stop_Enable;
  }
  else
  {
    /* Disable the STOP condition generation */
    I2C->CR &= I2C_Stop_Disable;
  }
}

/*******************************************************************************
* Function Name  : I2C_AcknowledgeConfig                                      
* Description    : Enables or disables I2C acknowledge feature.               
* Input          : - NewState: new state of the I2C Acknowledgement. 
*                    This parameter can be: ENABLE or DISABLE. 
* Output         : None                     
* Return         : None.                                                      
*******************************************************************************/
void I2C_AcknowledgeConfig(FunctionalState NewState)
{
  if (NewState == ENABLE)
  {
    /* Enable the acknowledgement */
    I2C->CR |= I2C_Ack_Enable;
  }
  else
  {
    /* Disable the acknowledgement */
    I2C->CR &= I2C_Ack_Disable;
  }
}