最近打算寫EEPROM，本着單使用官方手冊就搞定這個模拟EEPROM,最後還是借鑒了官方的例程
一、先來看一下我們要操作的記憶體空間的大小和可操作的位址在哪裡？
1)從上圖可知S32K148的FlexRAM 的最大空間為4k,是以說他可模拟的EEPROM最大為4k（S32K的EEPROM按位元組讀取的是由FlexRAM模拟最大4K，S32K的EEPROM按最小扇區2K讀取的是由FlexNvm模拟最大64K）
2)從上面兩張圖可以看出來我們要操作的EEPROM的首位址是在0X14000000
二、了解最基本的記憶體知識後，下來我們看一下操作FLASH寄存器的具體步驟
這個流程圖是關于Flash操作寄存器的通用步驟，這個你可以仔細看S32DS生成的驅動代碼，都是按照這個流程圖。
三、基本常識就是這些，然後借鑒一下Main.c代碼對Flash的操作流程
/* Including necessary module. Cpu.h contains other modules needed for compiling.*/
#include "Cpu.h"
volatile int exit_code = 0;
/* User includes (#include below this line is not maintained by Processor Expert) */
/*
* Flash選配記憶體空間分段
* */
#define BUFFER_SIZE 0x20u /* Size of data source */
#define FLASHaddNUM_ERASE 0
#define bool _Bool
#define true 1
#define false 0
#define _Bool bool
flash_ssd_config_t flashSSDConfig;
uint8_t sourceBuffer[BUFFER_SIZE]={1,2,3,4,0,0,7};
uint8_t sourceReadBuffer[BUFFER_SIZE]={1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0};
/*!
\brief The main function for the project.
\details The startup initialization sequence is the following:
* - startup asm routine
* - main()
*/
void CCIF_Handler(void);
START_FUNCTION_DECLARATION_RAMSECTION
void CCIF_Callback(void)
END_FUNCTION_DECLARATION_RAMSECTION
/* 2020.03.17
* 使用FlexRAM模仿EEPROM
* 可以最大分區出4k的EEPROM空間，并且記憶體可按照單個位元組進行讀取
*
* */
int main(void)
{
/* Write your local variable definition here */
status_t ret; /* Store the driver APIs return code */
uint32_t address;
uint32_t size;
uint32_t failAddr;
flash_callback_t pCallBack;
/*** Processor Expert internal initialization. DON'T REMOVE THIS CODE!!! ***/
#ifdef PEX_RTOS_INIT
PEX_RTOS_INIT(); /* Initialization of the selected RTOS. Macro is defined by the RTOS component. */
#endif
/*** End of Processor Expert internal initialization. ***/
CLOCK_SYS_Init(g_clockManConfigsArr, CLOCK_MANAGER_CONFIG_CNT,
g_clockManCallbacksArr, CLOCK_MANAGER_CALLBACK_CNT);
CLOCK_SYS_UpdateConfiguration(0U, CLOCK_MANAGER_POLICY_AGREEMENT);
/* Install interrupt for Flash Command Complete event */
INT_SYS_InstallHandler(FTFC_IRQn, CCIF_Handler, (isr_t*) 0); //CCIF_Handler代表了一個形參為void,傳回值為void的函數
INT_SYS_EnableIRQ(FTFC_IRQn);
/* Enable global interrupt */
INT_SYS_EnableIRQGlobal();
ret =FLASH_DRV_Init(&Flash1_InitConfig0,&flashSSDConfig);
DEV_ASSERT(STATUS_SUCCESS == ret);
#if 0
/*檫除EEPROM的存儲空間*/
ret = FLASH_DRV_EraseAllBlock(&flashSSDConfig); //實作寫指令的流程圖中的步驟，将之前刷寫的記憶體全部删除
DEV_ASSERT(STATUS_SUCCESS == ret);
/* Verify the erase operation at margin level value of 1 */
ret = FLASH_DRV_VerifyAllBlock(&flashSSDConfig, 1u);
DEV_ASSERT(ret == STATUS_SUCCESS );
FLASH_DRV_Init(&Flash1_InitConfig0,&flashSSDConfig);
#endif
/* 2020.03.17 分區這個函數必須使用
* 選配分出記憶體分區段
* uEEEDataSizeCode FCCOB4 0X2選擇4K 的EEPROM空間
* uDEPartitionCode FCCOB5 0x8選擇64K 的EEPROM空間
* uCSEcKeySize FCCOB1 CSEc加密服務選項 無
* uSFE FCCOB2 僅驗證屬性關閉
* flexRamEnableLoadEEEData FCCOB3 0 複位期間是否加載資料 加載
* */
ret=FLASH_DRV_DEFlashPartition(&flashSSDConfig,0x2,0x4,0x0,false,true);
DEV_ASSERT(STATUS_SUCCESS==ret);
FLASH_DRV_Init(&Flash1_InitConfig0,&flashSSDConfig);
/* 2020.03.17
* 選配分出記憶體分區段
* flexRamFuncCode FCCOB1 EEE_ENABLE 使能FlexRAM 模拟EEPROM
* byteOfQuickWrite FCCOB4 FCCOB5
* pEEPROMStatus EEPROM狀态 結構體中三個狀态
* */
FLASH_DRV_SetFlexRamFunction(&flashSSDConfig,EEE_ENABLE,0x00,NULL);
DEV_ASSERT(STATUS_SUCCESS==ret);
#if 1
/**嘗試寫單個位元組到EEPROM的記憶體中**/
/* Try to write data to EEPROM if FlexRAM is configured as EEPROM */
if (flashSSDConfig.EEESize != 0u)
{
address = flashSSDConfig.EERAMBase; //1400 0000
size = sizeof(uint32_t);
//sourceBuffer[0u] = 0x01;
ret = FLASH_DRV_EEEWrite(&flashSSDConfig, address, 1, sourceBuffer);
DEV_ASSERT(STATUS_SUCCESS == ret);
#if 1
/* Verify the written data */
if(sourceBuffer[0] != *((uint8_t *)address))
{
/* Failed to write data to EEPROM */
exit_code = 1u;
return exit_code;
}
#endif
#if 0
/* Try to update one byte in an EEPROM address which isn't aligned */
address = flashSSDConfig.EERAMBase + 1u;
size = sizeof(uint8_t);
//sourceBuffer[1u] = 0x11u;
ret = FLASH_DRV_EEEWrite(&flashSSDConfig, address, 1, sourceBuffer+1);
DEV_ASSERT(STATUS_SUCCESS == ret);
/* Then verify */
if (sourceBuffer[1u] != *(uint8_t *)address)
{
/* Failed to update data to EEPROM */
exit_code = 1u;
return exit_code;
}
#endif
/**實作向FlexRAM模拟EEPROM的第四個位元組實作刷寫更新**/
address = flashSSDConfig.EERAMBase+4; //1400 0000
size = sizeof(uint32_t);
//sourceBuffer[2u] = 0x22u;
/*如果位址讀出的資料 不等于sourceBuffer5的資料 則更新資料*/
if (sourceBuffer[4u] != *(uint8_t *)address)
{
sourceBuffer[4u]=(*(uint8_t *)address)+1;
sourceReadBuffer[4]=sourceBuffer[4u];
}
else if(0==*(uint8_t *)address)
{
sourceBuffer[4u]=(*(uint8_t *)address)+1;
sourceReadBuffer[4]=sourceBuffer[4u];
}
ret = FLASH_DRV_EEEWrite(&flashSSDConfig, address, 1, sourceBuffer+4);
DEV_ASSERT(STATUS_SUCCESS == ret);
#if 1
/* Verify the written data */
if (sourceReadBuffer[4] != *(uint8_t *)address)
{
/* Failed to write data to EEPROM */
exit_code = 1u;
return exit_code;
}
#endif
/**嘗試寫多個位元組到EEPROM的記憶體中**/
#if 1
address = flashSSDConfig.EERAMBase+0x10; //1400 0000
size = sizeof(sourceReadBuffer)/sizeof(sourceReadBuffer[0]);
ret = FLASH_DRV_EEEWrite(&flashSSDConfig, address, size, sourceReadBuffer);
DEV_ASSERT(STATUS_SUCCESS == ret);
/* Verify the written data */
if (sourceReadBuffer[0u] != *(uint8_t *)address)
{
/* Failed to write data to EEPROM */
exit_code = 1u;
return exit_code;
}
#endif
}
#endif
/* Write your code here */
/* For example: for(;;) { } */
/*** Don't write any code pass this line, or it will be deleted during code generation. ***/
/*** RTOS startup code. Macro PEX_RTOS_START is defined by the RTOS component. DON'T MODIFY THIS CODE!!! ***/
#ifdef PEX_RTOS_START
PEX_RTOS_START(); /* Startup of the selected RTOS. Macro is defined by the RTOS component. */
#endif
/*** End of RTOS startup code. ***/
/*** Processor Expert end of main routine. DON'T MODIFY THIS CODE!!! ***/
for(;;) {
if(exit_code != 0) {
break;
}
}
return exit_code;
/*** Processor Expert end of main routine. DON'T WRITE CODE BELOW!!! ***/
} /*** End of main routine. DO NOT MODIFY THIS TEXT!!! ***/
START_FUNCTION_DEFINITION_RAMSECTION
void CCIF_Callback(void)
{
/* Enable interrupt for Flash Command Complete */
if ((FTFx_FCNFG & FTFx_FCNFG_CCIE_MASK) == 0u)
{
FTFx_FCNFG |= FTFx_FCNFG_CCIE_MASK;
}
}
END_FUNCTION_DEFINITION_RAMSECTION
void CCIF_Handler(void)
{
/* Disable Flash Command Complete interrupt */ // 禁用 flash指令完成中斷
FTFx_FCNFG &= (~FTFx_FCNFG_CCIE_MASK);
return;
}
/* END main */
/*!
** @}
*/
主要還是借鑒了S32KDS生成的Demo例程中的具體操作流程。然後就可以實作指定的記憶體讀寫，效果如下。
第一次刷寫 可以看到0x14000005 資料為00 (這個記憶體空間的讀取是從右往左，低位元組到高位元組)
第二次刷寫 可以看到0x14000005 資料為01