How to overwrite System memory in STM32F40x?

Question

STM

How to overwrite System memory in STM32F40x?

1. Programmatically
   
2. Via OpenOCD
   

In short, all attempts are unsuccessful. And it's not clear what erase should be done before recording (since it's Flash)...

Answer 1

No way. The bootloader is NOT overwritten.
Section 3.2.1 - Flash Memory Organization
<...>
The information block is divided into two parts:
1. System memory: used to boot the device in System memory boot mode. The area is
reserved for use by STMicroelectronics and contains the boot loader which is used to
reprogram the Flash memory through the selected communication interface. It is
programmed by ST when the device is manufactured, and protected against spurious
write/erase operations. For further details, please refer to AN2606.
The information block is divided into two parts:
1. System Memory: Used to boot the device into boot mode from System Memory. This area is reserved by STMicroelectronics and contains the bootloader that is used to reprogram the Flash memory via the selected communication interface. This area is programmed by the ST when the device is manufactured and is protected from spurious write/erase operations. Please refer to AN2606 for details.
Start AN2606:
Introduction
The bootloader is stored in the internal boot ROM memory (system memory) of STM32
devices. It is programmed by ST during production. Its main task is to download the
application program to the internal Flash memory through one of the available serial
peripherals (USART, CAN, USB, I2C, SPI, etc.). A communication protocol is defined for
each serial interface, with a compatible command set and sequences. This document
applies to the products listed in Table 1. They are referred to as STM32 throughout the
document.
The bootloader is written in the internal boot ROM memory (system memory) of the STM32 controllers
Actually, there is no point in translating further).