STM32F1XX HAL_FLASH_Program dont support 8bytes? or go 16bytes space waste.

[Nicolas Felipe]

Posted on June 26, 2017 at 04:00

Hi, im trying to program (8byte) 500 lenght buffer into Internal an STM32F103xx microcontroller, i know how to write but

char receive_data[500]; / Char Belongs to 8bytes

but in STM32F1xx_hal_flash.h

#define FLASH_TYPEPROGRAM_HALFWORD ((uint32_t)0x01) /*!<Program a half-word (16-bit) at a specified address.*/

#define FLASH_TYPEPROGRAM_WORD ((uint32_t)0x02) /*!<Program a word (32-bit) at a specified address.*/

#define FLASH_TYPEPROGRAM_DOUBLEWORD ((uint32_t)0x03) /*!<Program a double word (64-bit) at a specified 

and 8bytes?

in other series like STM32F4XX we can find 8bytes support.

if

(TypeProgram ==

http://www.disca.upv.es/aperles/arm_cortex_m3/llibre/st/STM32F439xx_User_Manual/group__flash__type__program.html#gac975d7139325057ed0069c6b55e4faed

)00190     {00191      

/*Program byte (8-bit) at a specified address.*/

00192      

http://www.disca.upv.es/aperles/arm_cortex_m3/llibre/st/STM32F439xx_User_Manual/group__flash__exported__functions.html#ga1cf2729cad60da1faeba294904235b02

(Address, (uint8_t) Data);00193     }

and we have the FLASH_TYPEPROGRAM_BYTE.

i was tempted to addit to this STM32F1XX function but dont look any 8byte friendly with the 

nbiterations var.

if(status == HAL_OK)

{

if(TypeProgram == FLASH_TYPEPROGRAM_HALFWORD)

{

/* Program halfword (16-bit) at a specified address. */

nbiterations = 1;

}

else if(TypeProgram == FLASH_TYPEPROGRAM_WORD)

{

/* Program word (32-bit = 2*16-bit) at a specified address. */

nbiterations = 2;

}

else

{

/* Program double word (64-bit = 4*16-bit) at a specified address. */

nbiterations = 4;

}

for (index = 0; index < nbiterations; index++)

{

FLASH_Program_HalfWord((Address + (2*index)), (uint16_t)(Data >> (16*index)));

#if defined(FLASH_BANK2_END)

if(Address <= FLASH_BANK1_END)

{

#endif /* FLASH_BANK2_END */

/* Wait for last operation to be completed */

status = FLASH_WaitForLastOperation((uint32_t)FLASH_TIMEOUT_VALUE);

/* If the program operation is completed, disable the PG Bit */

CLEAR_BIT(FLASH->CR, FLASH_CR_PG);

#if defined(FLASH_BANK2_END)

}

for example im gonna program : 

char strJsonExtracted[] = '{\'set\':\'mf\',\'d\':\'2\',\'m\':\'22\',\'a\':\'17\',\'h\':\'18\',\'s\':\'45\'}';

(8  bytes buffer).

if the 

FLASH_TYPEPROGRAM_HALFWORD is used i guess lot of space will get wasted because will se 16bytes when needed is just 8bytes and

, am i wrong? or this would be the best option? thanks.

[misagh]

Posted on June 26, 2017 at 10:28

Hi  Nicolas,

I think you have a simple choice to use your memory more efficiently: making your data to 16-bit data, which contains two cells of your array, and write it to the flash memory. This is a simple example:

char strJsonExtracted[] = '{\'set\':\'mf\',\'d\':\'2\',\'m\':\'22\',\'a\':\'17\',\'h\':\'18\',\'s\':\'45\'}';

uint16_t* dataPointer;

dataPointer = (uint16_t*)strJsonExtracted;

for(index = 0; index < sizeof(strJsonExtracted)/2; index++){

   FLASH_Program_HalfWord((Address + (2*index)), *dataPointer);

}

Hope it would be help.

Bests,

Misagh

[Nicolas Felipe]

Posted on June 27, 2017 at 04:49

thank you, great difference. now half size and efficiency in every sector.