?? nvm.c
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/*
*********************************************************************************************************
* Freescale MC9S12 Processor Support
*
* Non Volatile Memory Read / Write
*
* File : nvm.c
*
* By : GeorgeWong
* : Eric Shufro
*
* Rev. Hist. : 08/12/2005 - Created
* 08/25/2005 - EEPROM_Erase_Sector
* Flash_Erase_Block
* 09/17/2006 - Cleaned up
*
* Description: Provides low level hardware functions for use with portable application code
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* INCLUDES
*********************************************************************************************************
*/
#include <includes.h>
/*
*********************************************************************************************************
* CONSTANTS
*********************************************************************************************************
*/
/*
*********************************************************************************************************
* EEPROM INITIALIZATION
*
* Description : This function initializes the Non Volatile EEPROM control registers and must be called
* before attempting to write or erase an EEPROM sector.
*
* Arguments : sysclk, the CPU clock frequency (SYSCLK) driven by the onboard oscillator or the
* PLL if enabled.
*
* Returns : None.
*
* Notes : 1) See bsp.c, BSP_CPU_ClkFreq(), as this function may be used to determine the SYSCLK
* frequency.
*********************************************************************************************************
*/
void EEPROM_Init (INT32U sysclk)
{
INT8U eclk_val;
if (sysclk >= 12000) { /* If the SYSCLK is > 12MHz, then set FDIV8 bit */
eclk_val = (sysclk / (8*200)) - 1; /* Compute the correct divider value */
ECLKDIV |= ECLKDIV_PRDIV8_MASK | eclk_val; /* Write the ECLKDIV register with the correct settings */
} else {
eclk_val = (sysclk / 200) - 1; /* Compute the correct divider value */
ECLKDIV |= eclk_val; /* Write the ECLKDIV register with the correct settings */
}
ESTAT |= (ESTAT_PVIOL_MASK | ESTAT_ACCERR_MASK); /* Clear any error flags */
}
/*
*********************************************************************************************************
* EEPROM WRITE
*
* Description : This function writes a 16-bit word to EEPROM
*
* Arguments : address, the destination EEPROM address to write the data
* data, the data to write to argument address.
*
* Returns : NVM_NO_ERR - EEPROM Write Success
* NVM_ODD_ACCESS_ERR - EEPROM Write Error, Address not on an even address boundry
* NVM_ACCESS_ERR - EEPROM Write Error, Access Violation
* NVM_PROTECTION_ERR - EEPROM Write Error, Attempted to write a protected sector
*
* Notes : None.
*********************************************************************************************************
*/
INT8S EEPROM_Write_Word (INT16U address, INT16U data)
{
while (!ESTAT_CBEIF) { /* Wait for EEPROM access controller to become ready */
;
}
ESTAT = (ESTAT_ACCERR_MASK | ESTAT_PVIOL_MASK); /* Clear existing error flags */
if (address & 0x0001) {
return (NVM_ODD_ACCESS_ERR); /* Address is NOT aligned on an even boundry? */
}
(*(INT16U *)address) = data; /* Write the data to the specified address */
ECMD = ECMD_CMDB5_MASK; /* Store programming command in FCMD */
ESTAT_CBEIF = 1; /* Execute the command */
if (ESTAT_ACCERR) { /* Check if there has been an access error */
return (NVM_ACCESS_ERR); /* Return an Access Error code */
}
if (ESTAT_PVIOL) { /* Check if there has been a protection error */
return (NVM_PROTECTION_ERR); /* Return a Protection Error code */
}
return (NVM_NO_ERR); /* Return No Error */
}
/*
*********************************************************************************************************
* EEPROM ERASE SECTOR
*
* Description : This function erases a 4-byte sector of EEPROM
*
* Arguments : address, the start of the 4-byte sector to address
*
* Returns : NVM_NO_ERR - EEPROM Write Success
* NVM_ODD_ACCESS_ERR - EEPROM Write Error, Address not on an even address boundry
* NVM_ACCESS_ERR - EEPROM Write Error, Access Violation
* NVM_PROTECTION_ERR - EEPROM Write Error, Attempted to write a protected sector
*
* Notes : None.
*********************************************************************************************************
*/
INT8S EEPROM_Erase_Sector (INT16U address)
{
while (!ESTAT_CBEIF) { /* Wait for EEPROM access controller to become ready */
;
}
ESTAT = (ESTAT_ACCERR_MASK | ESTAT_PVIOL_MASK); /* Clear existing error flags */
if (address & 0x0001) {
return (NVM_ODD_ACCESS_ERR); /* Address is NOT aligned on an even boundry? */
}
(*(INT16U *)address) = 0xFFFF; /* Write the data to the specified address */
ECMD = ECMD_CMDB6_MASK; /* Store programming command in FCMD */
ESTAT_CBEIF = 1; /* Execute the command */
if (ESTAT_ACCERR) { /* Check if there has been an access error */
return (NVM_ACCESS_ERR); /* Return an Access Error code */
}
if (ESTAT_PVIOL) { /* Check if there has been a protection error */
return (NVM_PROTECTION_ERR); /* Return a Protection Error code */
}
return (NVM_NO_ERR); /* Return No Error */
}
/*
*********************************************************************************************************
* EEPROM Read
*
* Description : This function reads a 16-bit word from the specified address in EEPROM
*
* Arguments : address, the start of the 16-bit data to read
*
* Returns : The 16-bit word stored in location 'address'
*
* Notes : None.
*********************************************************************************************************
*/
INT16U EEPROM_Read_Word (INT16U address)
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