STM32L: does it use NOR Flash?

[jpnorair2]

Posted on January 24, 2013 at 07:53

I've noticed that STM32L initializes Flash to 00 instead of FF.  Yes, it has an EEPROM section that can be used for 4KB of NV data storage, which is great.  I suspect that is actually NOR Flash as well.

Anyway, if ST is listening, I think there needs to be documentation about the peculiarity of the STM32L Flash.  There is none that I can find.  There are not a thousand people trying to implement flash file systems on the STM32L, but there are enough that it is worth making a point of it somewhere in the Users' Guide or the Programming Guide.

[Tesla DeLorean]

Posted on January 24, 2013 at 13:11

The EEPROM is rated at 300K cycles, the FLASH at 10K cycles, somehow I suspect they use different technology.

An SD card that does ecc, wear leveling and remapping sounds a lot more appealing.

[Amel NASRI]

Posted on January 31, 2013 at 15:27

Isn't the ''

http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/PROGRAMMING_MANUAL/CD00242299.pdf

'' the document you are looking for?

ST.MCU

[Tesla DeLorean]

Posted on January 31, 2013 at 15:46

I think what's being asked in these sort of questions is one of technology/geometry being used by ST, and how that might differ to other competing technology, or ones the poster is more familiar with. ie Why the erased state is zero vs one, is there one less transistor or one more? How does the memory characterization correlate with other similar parts in the portfolio, which ones?

I find ST documentation to be lacking in specificity.

I know I've had to fill in reports, declarations and certifications which expect details of non-volatile memory including capacity and implementation details.

[jpnorair2]

Posted on February 01, 2013 at 01:59

STM32L uses 00 for erase state, and STM32F uses FF.  I looked at the programming manual first, but I could not confirm this attribute from the programming manual.  I think the 00 erase state feature should be written on the first or second page, as many users of 32L must certainly be users of 32F, also.