Flash can be read like a RAM from the ARM core, but cannot be written like a RAM.
If you need more RAM, then you should consider an MCU with more RAM. Or alternatively use external RAM (requires MCU with external memory bus).
Regards,
Bernhard.
Thanks for the answer. How to write to RAM during program execution? Any serial interface?
"Flash can be read like a RAM from the ARM core, but cannot be written like a RAM."
How is the writing performed in this case?
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Sorry, my bad. How to write to FLASH during program execution? SPI, I2C, UART?
Look into the specification of the respective flash device: