前言
CYPRESS的PSOC BLE和PROC BLE芯片内部有个512Bytes的SFLash，用于保存用户指定的数据，接下来分享下如何对该区域进行读写
SFLASH的内部结构
从上图可以看出，SFLASH共有4行，每行128Bytes，其中第0行的前6个字节是存放BLE的MAC地址用的，用户不能修改否则MAC地址就会被篡改了。同时，SFLASH地址从0x0FFF F2000x0FFF F380.
- 写SFLASH的关键代码实现
根据《cy_boot Component v5.30》手册的第8章所说，写SFLASH都是一次性写入128Bytes数据，不能一个Bytes一个Bytes地写入SFlash，但是我进行了相应的修改，一行可以在SFLASH地址范围指定的地方写入数据，代码如下：
1. 使用到的宏定义：
/*****************************************************
* Enums and macros
*****************************************************/
#define SWITCH_PRESSED (0u) /* Active low user switch on BLE Pioneer kit */
#define USER_SFLASH_ROW_SIZE (128u) /* SFlash row size for 128KB flash BLE device. For other PSoC 4 BLE devices
* with higher flash size, this example project might need some modification.
* Please check the device datasheet and TRM before using this code on non 128KB
* flash devices */
#define SFLASH_STARTING_VALUE (0x00) /* Starting value to be stored in user SFlash to demonstrate SFlash write API */
#define USER_SFLASH_ROWS (4u) /* Total number of user SFlash rows supported by the device */
#define USER_SFLASH_BASE_ADDRESS (0x0FFFF200u) /* Starting address of user SFlash row for 128KB PSoC 4 BLE device */
#define LOAD_FLASH 0x80000004
#define WRITE_USER_SFLASH_ROW 0x80000018
#define USER_SFLASH_WRITE_SUCCESSFUL 0xA0000000
2. 关键代码的实现：
/*******************************************************************************
* Function Name: WriteUserSFlashRow
********************************************************************************
* Summary:
* This routine calls the PSoC 4 BLE device supervisory ROM APIs to update
* the user configuration area of Supervisory Flash (SFlash).
*
* Parameters:
* userRowNUmber - User config SFlash row number to which data is to be written
* dataPointer - Pointer to the data to be written. This API writes one row of
* user config SFlash row at a time.
*
* Return:
* uint32 - state of the user config SFlash write operation.
*
*******************************************************************************/
#if defined (__GNUC__)
#pragma GCC optimize ("O0")
#endif /* End of #if defined (__GNUC__) */
uint32 WriteUserSFlashRow(uint8 userRowNUmber, uint32 *dataPointer,uint8_t datalength,uint8_t address)
{
uint8 localCount;
volatile uint32 retValue=0;
// volatile uint32 cmdDataBuffer[(CY_FLASH_SIZEOF_ROW/4) + 2];
volatile uint32 cmdDataBuffer[datalength+2];
volatile uint32 reg1,reg2,reg3,reg4,reg5,reg6;
/* Store the clock settings temporarily */
reg1 = CY_GET_XTND_REG32((void CYFAR *)(CYREG_CLK_SELECT));
reg2 = CY_GET_XTND_REG32((void CYFAR *)(CYREG_CLK_IMO_CONFIG));
reg3 = CY_GET_XTND_REG32((void CYFAR *)(CYREG_PWR_BG_TRIM4));
reg4 = CY_GET_XTND_REG32((void CYFAR *)(CYREG_PWR_BG_TRIM5));
reg5 = CY_GET_XTND_REG32((void CYFAR *)(CYREG_CLK_IMO_TRIM1));
reg6 = CY_GET_XTND_REG32((void CYFAR *)(CYREG_CLK_IMO_TRIM2));
/* Initialize the clock necessary for flash programming */
CY_SET_REG32(CYREG_CPUSS_SYSARG, 0x0000e8b6);
CY_SET_REG32(CYREG_CPUSS_SYSREQ, 0x80000015);
/******* Initialize SRAM parameters for the LOAD FLASH command ******/
/* byte 3 (i.e. 00) is the Macro_select */
/* byte 2 (i.e. 00) is the Start addr of page latch */
/* byte 1 (i.e. d7) is the key 2 */
/* byte 0 (i.e. b6) is the key 1 */
cmdDataBuffer[0]=0x0000d7b6|(address<<16);
/****** Initialize SRAM parameters for the LOAD FLASH command ******/
/* byte 3,2 and 1 are null */
/* byte 0 (i.e. 7F) is the number of bytes to be written */
cmdDataBuffer[1]=0x00000000|datalength-1;
/* Initialize the SRAM buffer with data bytes */
// cmdDataBuffer[2] = *dataPointer;
for(localCount = 0; localCount < datalength; localCount++)
{
cmdDataBuffer[localCount + 2 = dataPointer[localCount];
}
/* Write the following to registers to execute a LOAD FLASH bytes */
CY_SET_REG32(CYREG_CPUSS_SYSARG, &cmdDataBuffer[0]);
CY_SET_REG32(CYREG_CPUSS_SYSREQ, LOAD_FLASH);
/****** Initialize SRAM parameters for the WRITE ROW command ******/
/* byte 3 & 2 are null */
/* byte 1 (i.e. 0xeb) is the key 2 */
/* byte 0 (i.e. 0xb6) is the key 1 */
cmdDataBuffer[0 = 0x0000ebb6;
/* byte 7,6 and 5 are null */
/* byte 4 is desired SFlash user row
* Allowed values 0 - row 4
1 - row 5
2 - row 6
3 - row 7 */
cmdDataBuffer[1 = (uint32) userRowNUmber;
/* Write the following to registers to execute a WRITE USER SFlash ROW command */
CY_SET_REG32(CYREG_CPUSS_SYSARG, &cmdDataBuffer[0]);
CY_SET_REG32(CYREG_CPUSS_SYSREQ, WRITE_USER_SFLASH_ROW);
/* Read back SYSARG for the result. 0xA0000000 = SUCCESS; */
retValue = CY_GET_REG32(CYREG_CPUSS_SYSARG);
/* Restore the clock settings after the flash programming is done */
CY_SET_XTND_REG32((void CYFAR *)(CYREG_CLK_SELECT),reg1);
CY_SET_XTND_REG32((void CYFAR *)(CYREG_CLK_IMO_CONFIG),reg2);
CY_SET_XTND_REG32((void CYFAR *)(CYREG_PWR_BG_TRIM4),reg3);
CY_SET_XTND_REG32((void CYFAR *)(CYREG_PWR_BG_TRIM5),reg4);
CY_SET_XTND_REG32((void CYFAR *)(CYREG_CLK_IMO_TRIM1),reg5);
CY_SET_XTND_REG32((void CYFAR *)(CYREG_CLK_IMO_TRIM2),reg6);
return retValue;
}
#if defined (__GNUC__)
#pragma GCC reset_options
#endif /* End of #if defined (__GNUC__) */
3. 读SFLASH的内容
直接读x0FFF F200~0x0FFF F380地址的内容即可，代码实现如下:
/*******************************************************************************
* Function Name: ReadDataFromSFlash
********************************************************************************
*
*
*
* 读取SFlash中的数据
* \param none
* \return
* None
* SFlash中有506Bytes字节的用户可配置的空间
******************************************************************************/
uint8_t ReadDataFromSFlash()
{
uint8_t FlashData=0;
uint8_t *sflashPtr=(uint8_t *)USER_SFLASH_BASE_ADDRESS;//SFlash的首地址
sflashPtr=sflashPtr+6;//前6字节是保存MAC地址，不能修改
FlashData=*sflashPtr;
return FlashData;
}
