STM32H7A3AII6Q Internal bootloader boot for firmware update.

[shubhenduatadben]

Hello,

    I'm working into writing firmware image to a STM32H7A3AII6Q via internal boot-loader. I'm using AN2606 and AN3155 as reference documents. 
    The boot-loader entry sequence I'm using:
State 1: BOOT0: high

              RST: low

State 2: Wait 200 ms

State 3: BOOT0: high

              RST: high

Then I'm sending 0x7F over USART2 but, getting no response(0x79).

Can you please help me what might be wrong here?

[mƎALLEm]

Hello,

You didn't tell what IOs you have used for USART2? PA2 and PA3?

If yes check your wiring (continuity test). Use an oscilloscope to check what happens on Tx and Rx.

 

[shubhenduatadben]

The board uses USART2: PA2,PA3. The USART is working well when connected to other boards and running application firmware. But, when isolated and tested by serial, there is no activity on USART: TX in the oscilloscope. 

The USB serial parameters:

BAUD: 115200

PARITY: EVEN

STOP: 1

[mƎALLEm]

---

@shubhenduatadben wrote:

The USB serial parameters:

BAUD: 115200

PARITY: EVEN

STOP: 1

---

You need to check that USB to UART bridge..connect its tx and rx and use an Hyperterminal and check if what you send you receive it. 

And use CubeProgrammer to connect to the ST bootloader: 

 

[TDK]

You need to be in the bootloader in order for 0x7F to have an effect. AN2606 lists the ways to enter the bootloader. Most commonly, holding BOOT0 high during reset will enter the bootloader under most circumstances.