Problem with STM32F407 Flash sector after programming

[Elijah Fine]

Posted on May 21, 2018 at 10:01

Hello there,

I've tried to do flash logger function for my device based on

http://www.kynix.com/uploadfiles/pdf8798/STM32F407VET6.pdf

and found some problem with flash:

If I uncomment function for clear sector, after load program my dummy data on first page is cleared before i start.

what I've done :

1) In .ld file I've define some sections:

MEMORY{ FLASH_S0 (rx) : ORIGIN = 0x08000000, LENGTH = 16K FLASH_S1 (rx) : ORIGIN = 0x08004000, LENGTH = 16K /* Reserved for OS*/ FLASH_S2 (rx) : ORIGIN = 0x08008000, LENGTH = 16K /* LogPage1 */ FLASH_S3 (rx) : ORIGIN = 0x0800C000, LENGTH = 16K /* LogPage2 */ ...in SECTIONS :.logPage1 : { . = ALIGN(4); KEEP(*(.logPage1)) /*Startup code */ . = ALIGN(4); } >FLASH_S2 .logPage2 : { . = ALIGN(4); KEEP(*(.logPage2)) /* Startup code */ . = ALIGN(4); } >FLASH_S3 

2) in code create two const data arrays:

volatile const uint32_t __attribute__((section ('.logPage1'))) log_data_page1[2] = {0xDEADBEEF, 0xDEADBEEF};volatile const uint32_t __attribute__((section ('.logPage2'))) log_data_page2[2] = {0xDEADBEEF, 0xDEADBEEF};

3)for test reason there was defined some data in header :

#define LOGPAGENUM 2#define LOGDATACOUNT 2#define LOGDATASIZE FLASHLogDataSize_32b#define FLASHPAGESIZE 0x4000#define FLASHSTARTADDR 0x08000000#define LOGFIRSTPAGE 2#define LOGSECONDPAGE 3#define SECTORCOUNT 12

4) and there is functions:

BOOL FLASHClear (uint8_t clearSector){ FLASH_Status status; if(clearSector >= SECTORCOUNT) return FALSE; FLASH_Unlock(); while(FLASH->SR & FLASH_SR_BSY) {} { uint32_t Temp = FLASH->CR; Temp &= ~(0xFUL << 3); // FLASH_CR_SNB [3:6] Temp |= (clearSector << 3); Temp |= FLASH_CR_SER; FLASH->CR = Temp; } FLASH->CR |= FLASH_CR_STRT; while(FLASH->SR & FLASH_SR_BSY) {} FLASH->CR &= ~FLASH_CR_SER; FLASH_Lock(); return status;}

and where it is called:

FLASHSectionPage FLASHLog_ActivePageSrch(TFLASHSector sectors[], uint32_t pageSize, uint8_t dataSize){ FLASHSectionPage page = FLASHSection_Page_None; uint32_t headData ; uint32_t tailData ; uint8_t scanPage = (uint8_t) page;// no While for less memory and CPU usage scanPage = NextSectionPage(scanPage); // FLASHSection_Page_None в LOGFIRSTPAGE headData = FLASHRead(sectors[scanPage].From); tailData = FLASHRead(sectors[scanPage].From+ pageSize - dataSize); if ( ((headData & EMPTYWORD) != EMPTYWORD) && ((tailData & EMPTYWORD) == EMPTYWORD) ){ page = (FLASHSectionPage)scanPage; } else { scanPage = NextSectionPage(scanPage); // LOGFIRSTPAGE в LOGSECONDPAGE headData = FLASHRead(sectors[scanPage].From); tailData = FLASHRead(sectors[scanPage].From+ pageSize - dataSize); if ( ((headData & EMPTYWORD) != EMPTYWORD) && ((tailData & EMPTYWORD) == EMPTYWORD) ){ page = (FLASHSectionPage)scanPage; } else {

// both page is full clear first and mark as active scanPage = NextSectionPage(scanPage); // LOGSECONDPAGE to LOGFIRSTPAGE FLASHClear (scanPage); page = (FLASHSectionPage)scanPage; } } return page; }

5) call of second function is like these:

page = FLASHLog_ActivePageSrch( sectors, LOGDATACOUNT * 0x4 , 0x4 );

6) sector is constatn array - map of MCU flash: TFLASHLogMap FLASHLog;

static const TFLASHSector sectors[] = { // STM32F40x, STM32F41x, STM32F42x, STM32F43x { 0x08000000UL, 0x08003FFFUL, 0 }, // 16 kB { 0x08004000UL, 0x08007FFFUL, 1 }, // 16 kB { 0x08008000UL, 0x0800BFFFUL, 2 }, // 16 kB { 0x0800C000UL, 0x0800FFFFUL, 3 }, // 16 kB { 0x08010000UL, 0x0801FFFFUL, 4 }, // 64 kB { 0x08020000UL, 0x0803FFFFUL, 5 }, // 128 kB { 0x08040000UL, 0x0805FFFFUL, 6 }, // 128 kB { 0x08060000UL, 0x0807FFFFUL, 7 }, // 128 kB { 0x08080000UL, 0x0809FFFFUL, 8 }, // 128 kB { 0x080A0000UL, 0x080BFFFFUL, 9 }, // 128 kB { 0x080C0000UL, 0x080DFFFFUL, 10 }, // 128 kB { 0x080E0000UL, 0x080FFFFFUL, 11 }, // 128 kB};

And so, if i've comment this line

FLASH->CR |= FLASH_CR_STRT;

after compile and debug I can see in memory in address 0x08008000 and 0x0800c000

DEADBEEF DEADBEEF

but if I just uncomment it and start debug there will be these data:

0x08008000 > FFFFFFFF FFFFFFFF

0x0800c000 > DEADBEEF DEADBEEF

Please help me to understand how is code for cleare page is done before I start, and how can I fix it. Thanks in advance.

#linker #flash #stm32f4