STM32 F4 System Memory Boot Mode and Read Protection

[Zt Liu]

Posted on November 01, 2017 at 07:33

Dear fellows, 

In STM32F4 series, 

Have you noticed that when Read Protection is enabled, with RDP Level 1,

The System Memory Boot mode has no response at least from UART1 and UART3.

(I confirm that TX pin has no response, as checked by oscilloscope. )

I've tried F446 and F410 Nucleo 64 Board on UART1 PA9/PA10 or UART3 PC10/PC11.

However, once the read protection is disabled, RDP back to 0, every thing works again.

(If I send 0x7F through UART, I got 0x79 as expected. )

If I remember correctly: in L4 series, even if Read Protection is enabled, the MCU still responses through UARTx.

.Zt

#stm32f446 #stm32f410 #system-bootloader

[Sergey .]

Posted on November 18, 2017 at 12:55

I've checked STM32F407G-DISC1 and Core407Z boards. Checked PA9/PA10, PB10/PB11 and PC10/PC11. Same behavior. No response with read protection set.

[Zt Liu]

Posted on November 20, 2017 at 04:54

�?¡�?µÑ€Ñ‘�?¶�?°,

thanks for your double check! 

For the moment, I am not able to check the assembly code in system memory.

Also due to security issue, I just have to implemented my own boot-loader.

Thanks again!

.Zt