Problem in using flash memory of STM32H745

[hryu.1]

MCU : STM32H745

Boot : booting from user main memory(0x08000000 )of flash memory ( boot0 :low)

compiler: IAR

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I am coding to write in address 0x08060000 of flash memory in Cortex M7 .

Cache is enabled, MPU is configured below

After at first writing 44444(0xad9c) , writing same value (44444) in same address , everything works well

But I have problem in writing different value(44443) in same address

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this is state of memory after writing 44444(0xad9c)

and this is state of memory after writing 44443 which is different value than before.

Memory is changed strangely .

since this, reading of the value will result in an error.

I don't understand why

[Tesla DeLorean]

Because the Flash lines are wide, have ECC, and cannot be written multiple times, even if just knocking down bits.

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I​f you want to change content expect to Erase first. Consider journalling data over subsequent words.