External Memory ( Help ! )

leventeyigel52 · ‎2012-01-03

Posted on January 03, 2012 at 14:44

Hello

I have to try use an external memory for writing and reading same data on stm32 discovery board.

Which type memory can i use ? EEPROM or FLASH ?

And how can i connect this device to my board ?

Is there anyone tried about it

#stm32 #memory #gpio

camille · ‎2012-01-03

Posted on January 03, 2012 at 16:44

Hi.

You can use EEPROM or Flash as you prefer, the main difference between the two technologies are access time (EEPROM is slower) and life span (longer for EEPROM).

Also on my opinion EEPROM is simpler to use because you can erase one byte a time but if you need quick read/write cycles or lot of memory, Flash would be a better choice.

To connect your memory on your board you can use I2C (look at the STM32C-Eval board schematics, it uses an EEPROM linked to the micro with I2C, and an example how to use it is given in the standard library). SPI and parallel memories are also available (with SPI you can get higher transfer rates).

Also if you don't really need an external memory the application note AN2594 explain how to use STM's internal Flash to emulate an EEPROM. And if you use the STM32L-Discovery the embedded micro have a ''true'' internal EEPROM.

Hope it will help you.

Regards.

robin.

mehmet.karakaya · ‎2012-01-03

Posted on January 03, 2012 at 17:51

hello Robin ,

the PDF mention an example application

but I couldnot find it attached

where can I download it ?

emalund · ‎2012-01-03

Posted on January 03, 2012 at 22:02

you do not say serial or parallel

camille · ‎2012-01-04

Posted on January 04, 2012 at 11:58

Hi.

You have to download the STM32F10x Standard peripheral library. Follow the link :

http://www.st.com/internet/mcu/product/221020.jsp

then click on ''Design support'' and you'll find the library in the bottom of the page, paragraph ''Firmware''.

In the library file the exemple is in ''Project\STM32F10x_StdPeriph_Examples\I2C\EEPROM''

Regards.

emalund · ‎2012-01-04

Posted on January 04, 2012 at 15:57

Robin:

you ASS U ME that the OP means serial, where do you have that knowledge from?

Erik

Wait for the OP to answer my question

leventeyigel52 · ‎2012-01-05

Posted on January 05, 2012 at 09:25

I will try it ! thanks Robin

leventeyigel52 · ‎2012-01-05

Posted on January 05, 2012 at 09:27

I will try it ! But my data is 3 or 4 mb so i want to make this way, however i will try again to emulate EEPROM to Flash Memory . thanks Robin