STM32f407 boot mode

[AKHIL6]

Hi I am using STM32F407 DISCOVERY BOARD and I am able to make the board change to boot mode using a another controller.

After boot mode change over I need to program the memory of STM32F407 DISCOVERY BOARD by UART communication.

Here I am unable to get the ack when I provide the sync command(0x7f).

But when I completely remove the power and provide the power back The 0x7f is acknowledged with 0x79. 

In real time application I cannot reset the power manually.

Am i missing anything ...? Please share your insights on this.

[waclawek.jan]

> I am able to make the board change to boot mode using a another controller.

How?

JW

[TDK]

If ACK isn't being sent, it doesn't sound like you're in the bootloader. Unless another interface is active first.