If RDP is set to level 2, it disables the read and writes access to flash using the internal flash code/program, Which is not correct behavior as per Data sheet

[jkamb.1]

..

[jkamb.1]

I tried to disable the JTAG by setting the RDP to level 2. It has disabled the JTAG access But I have flashed an application in internal flash which allows me to read and write internal flash using UART Now I am not able to read or write the internal flash. Will the RDP level 2 stop the access(read/write) to internal flash by the internal program also? I don't know what should I do now?

Here is what the datasheet says: In RDP level 2, I understand that flash read and write should be disabled via JTAG but Flash read or write should be allowed by an internal application/program stored in the internal flash.

[jkamb.1]

STM32F4 is used in this project

[Pavel A.]

Can you print out the option bytes from your program? Any sector-level WRP are set?

>  I don't know what should I do now?

Replace the MCU.

[S.Ma]

Check any errata doc for the chip.

If you are not able to access memory through usart, maybe there is something else that is wrong in the code. Use a blinky to check your code is not in exception mode.Maybe if using the stlink vcp doesn t work unless the debug is active?

[TDK]

> Will the RDP level 2 stop the access(read/write) to internal flash by the internal program also? I don't know what should I do now?

No, it does not. See reference manual:

 

I'm sure you've got something else going on there, which you're not going to be able to solve let alone debug due to RDP level 2.