eeprom_drv.c

飞思卡尔车身控制技术研讨会资料范例 基于LIN的收发通信

/*******************************************************************************/
/*
Copyright (c) 2008 Freescale Semiconductor
Freescale Confidential Proprietary
\file       EEPROM_Drv.c
\brief      EEPROM driver for S08DZ60
\author     Freescale Semiconductor
\author     B01246/ B07297
\version    0.1
\date       January/2008
*/
/*******************************************************************************/


/** Variable types */
#include "typedefs.h"
#include "EEPROM_Drv.h"


/*-- Global Variables ----------------------------------------------------------*/
UINT8   u8EEPROM_Tasks_Status;
UINT8   u8EEPROM_Tasks_Status_Previous;
UINT8  *pu8EEPROM_ByteData_ptr; 
UINT16  u16EEPROM_ByteAddress;
UINT16  u16EEPROM_ByteEraseAddress;
UINT16  u16EEPROM_SectAddress;
UINT8   u8EEPROM_Bytes;
UINT8   u8EEPROM_EraseBytes;
UINT8   u8EEPROM_Sectors;


/*******************************************************************************/
/**
* \brief    vfnEE_Init - Initialize EEPROM and FLASH Clock divisor.
* \author   B01246
* \param    unsigned char val : Value to be written to FCDIV.
* \return   void
* \todo     
*/
void vfnEE_Init(UINT8 val)
{
  if (FCDIV_DIVLD == 0) FCDIV = val; 
  u8EEPROM_Tasks_Status = NO_TASK_PENDING;
}

/*******************************************************************************/
/**
* \brief    IsEEPROMBusy - Perform command buffer empty check.
* \author   B01246/ B07297
* \param    void
* \return   Error code (unsigned char)
* \todo
*/
UINT8 IsEEPROMBusy(void)
{
    if ((FSTAT_FCBEF == 0)||(u8EEPROM_Tasks_Status != NO_TASK_PENDING))               
    
        return EEPROM_BUSY;
    else
        return EEPROM_READY;
}

/*******************************************************************************/
/**
* \brief    EE_GetByte - Reads an EEPROM byte from the address provided into the pointer provided.
* \author   B01246/ B07297
* \param    unsigned int Addr :Address of byte to be extracted
* \param    unsigned char * Data: Pointer to store the result.
* \return   Error code (unsigned char)
* \todo
*/
UINT8 EE_GetByte(UINT16 Addr,byte *Data)
{
  if ((Addr < EEPROMStart)||(Addr > EEPROMEnd)) // Is given address out of EEPROM area array ? 
    return ERR_RANGE;                  // If yes then error 
  
  if ((FSTAT & 0xC0) != 0xC0)          // Is reading from EEPROM possible? 
    return ERR_BUSY;                   // If no then error 
  
  *Data = *(volatile byte *) Addr;     // Return data from given address 
  return ERR_OK;                       // OK 
}

/*******************************************************************************/
/**
* \brief    EE_GetWord - Reads an EEPROM word from the address provided into the pointer provided.
* \author   B01246/ B07297
* \param    unsigned int Addr : Address of word value to be extracted
* \param    unsigned int * Data: Pointer to store the result.
* \return   void
* \todo
*/
UINT8 EE_GetWord(UINT16 Addr,UINT16 *Data)
{
  if ((Addr < EEPROMStart)||(Addr > (EEPROMEnd - 1))) // Is given address out of EEPROM area array ? 
    return ERR_RANGE;                  // If yes then error 
 
  if ((FSTAT & 0xC0) != 0xC0)          // Is reading from EEPROM possible? 
   return ERR_BUSY;                   // If no then error 

  *Data = *(volatile UINT16 *) Addr;   // Return data from given address 
  return ERR_OK;                       // OK 
}

/*******************************************************************************/
/**
* \brief    u8SectorEraseEEPROM - Requests the erasure of a given number of sectors starting from the address provided.
* \author   B01246/ B07297
* \param    unsigned int Addr : Address of the first sector to be erased.
* \param    unsigned char Sectors: Number of sectors to  be erased
* \return   Error code
* \todo
*/
UINT8 u8SectorEraseEEPROM(UINT16 AddrSect, UINT8 Sectors)
{
    /* Verify address within range */
    if ((AddrSect < EEPROMStart)    ||
            (AddrSect + 4*Sectors > EEPROMEnd+1))//each sector is 4 byte long
    {
        /* Address out of EEPROM valid range */
        return ERR_RANGE;     
    }
 
    /* Perform command buffer empty check; if EEPROM is accessible, proceed */
     if ((FSTAT_FCBEF == 0)||(u8EEPROM_Tasks_Status != NO_TASK_PENDING))               
    {
        /* EEPROM is busy, command cannot be performed now, try later */
        return ERR_BUSY;
    }
    /* Perform address alignment verification; if alignment = 4 byte-aligned, proceed */
    if ((AddrSect & 0x0003) != 0)
    {    
        /* Unaligned EEPROM Address (non-4-byte aligned), notify upper layer about this error */
        return ERR_MISALIGN;
    }
    /* Update Address and Data variables  */
    u16EEPROM_SectAddress = AddrSect;
    u8EEPROM_Sectors = Sectors;
    
    /* Proceed with Sector erase command */
    u8EEPROM_Tasks_Status = SECTOR_ERASE_REQUEST;

    /* Notify upper layer about request current status */
    return ERR_OK;
}    


/*******************************************************************************/
/**
* \brief    u8ByteWriteOnlyEEPROM - Requests the programming of an array of values, starting at a given address.
* \brief                            The destination is assumed to be ALREADY ERASED!
* \breif                            This function will NOT erase it prior to programming.
* \author   B01246/ B07297
* \param    unsigned int AddrByte : Address of the first byte destination to be programmed
* \param    unsigned char *Data8_ptr: Pointer to the values to be written
* \param    unsigned char Bytes: Number of bytes to be written.
* \return   Error code
* \todo
*/
UINT8 u8ByteWriteOnlyEEPROM(UINT16 AddrByte,UINT8 *Data8_ptr, UINT8 Bytes)
{
    UINT8 index;
    
    //Verify address within range
    if ((AddrByte < EEPROMStart)    ||
            (AddrByte + Bytes > EEPROMEnd+1))
    {
        //Address out of EEPROM valid range
        return ERR_RANGE;     
    }
    //Perform command buffer empty check; if EEPROM is accessible, proceed 
    if ((FSTAT_FCBEF == 0)||(u8EEPROM_Tasks_Status != NO_TASK_PENDING))               
    {
        //EEPROM is busy, command cannot be performed now, try later
        return ERR_BUSY;
    }
    //Check if Bytes are blank
    for (index=0; index<Bytes; index++)
    {
        if (*(volatile UINT8 *)(AddrByte +index) != 0xFF)
        {
            return ERR_NON_BLANK;
        }
    }
    //Update Address and Data variables
    u16EEPROM_ByteAddress = AddrByte;
    pu8EEPROM_ByteData_ptr = Data8_ptr;
    u8EEPROM_Bytes = Bytes;
    
    // Proceed with Word program command 
    u8EEPROM_Tasks_Status = BYTE_PROGRAM_REQUEST;

    // Notify upper layer about request current status 
    return ERR_OK;
}

/*******************************************************************************/
/**
* \brief    u8ByteWriteEEPROM  - Requests the programming of an array of values, starting at a given address.
* \brief                         An ERASE  request is sumbitted prior to Programming the bytes.
* \author   B01246/ B07297
* \param    unsigned int AddrByte : Address of the first byte destination to be programmed
* \param    unsigned char *Data8_ptr: Pointer to the values to be written
* \param    unsigned char Bytes: Number of bytes to be written.
* \return   Error code
* \todo
*/
UINT8 u8ByteWriteEEPROM(UINT16 AddrByte,UINT8 *Data8_ptr, UINT8 Bytes)