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Does STM32 have eeprom?
STM32 ARM uC’s like STM32F103 do not have EEPROM, so it is emulated by a software library.
What is __ Flashstringhelper?
The __FlashStringHelper is just special data type used for determining correct overloaded function/method for Flash strings. Anyway you can’t use strcmp as it’s for comparing two strings in RAM, but in the include
What is Arduino flash memory?
Flash memory (program space), is where the Arduino sketch is stored. SRAM (static random access memory) is where the sketch creates and manipulates variables when it runs. EEPROM is memory space that programmers can use to store long-term information.
How to store a variable in flash memory?
The short answer is to declare your variable with the const keyword. If your MCU actually remembers the value of your const variable (i.e. your sine computation actually works), it pretty much has to be stored in flash memory, otherwise it would be lost at the first reboot after programming. The long answer has to do with linker script.
How are variables stored in a microcontroller?
The short answer is to declare your variable with the const keyword. If your MCU actually remembers the value of your const variable (i.e. your sine computation actually works), it pretty much has to be stored in flash memory, otherwise it would be lost at the first reboot after programming.
Why is flash memory slower than RAM memory?
Among the reasons are: 1) depending on the chip, the access to FLASH memory can be much slower than RAM access (especially for writing) 2) FLASH can only be rewritten a limited number of times: it is not a problem for an occasional rewrite but if your code constantly rewrites FLASH memory, you can ruin it rather quicky.
Can a non const array be stored in Flash?
To answer the original question, you can write a linker script to force any variable to reside in a predetermined area of memory (declaring them const does not force the compiler to put it in FLASH, it is merely a strong suggestion). On the other hand, overabundance of FLASH is not in itself a good reason to keep a non- const array in flash.