This demo is targeted towards the Olimex STM32E407 board, with 1 MB internal Flash EEPROM and 196 kB internal RAM.

To program the bootloader into the internal flash on the STM32F407 microcontroller, the ST-LINK/V2 debugger interface was used. However, this is not required if you have another means of programming the internal flash.

To compile the demo programs you can use the STM32CubeIDE development environment. Note that STM32CubeIDE is cross-platform. The information outlined on this page applies to both Microsoft Windows and Linux users.

A MOD-USB-RS232 was connected to the EXT connector of the board to establish a serial communication connection between the board and the PC.

Two demo projects are included in the OpenBLT bootloader package. One for the bootloader itself and one for the demo user program. This user program is configured such that it can be programmed, into the internal flash memory of the microcontroller, during a firmware update with the bootloader.

The first step in getting the the bootloader up-and-running, is the creation of the Eclipse workspace in STM32CubeIDE. After starting STM32CubeIDE, you are prompted to open a workspace. It is easiest to create a new one in the following directory: .\Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\

To import the demo programs into the workspace, select File → Import from the program menu. Then select General → Existing Projects into Workspace. On the next screen you select the following directory as the root directory: .\Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\. Eclipse will automatically find the Boot and Prog projects and select them:

Click the Finish button to complete the project import operation.

Before the bootloader can be used, it needs to be built and programmed into the STM32F407ZG's internal flash memory. The steps in this section only need to be done once.

1. Set the project as the active project in Eclipse. This is achieved by clicking the Boot project in the Project Explorer to select it.
2. Delete the file \Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\Boot\Debug\openblt_olimex_stm32e407.elf.
3. Next, right-click the Boot project in the Project Explorer and select Refresh from the popup menu.
4. Finally, right-click the Boot project in the Project Explorer and select Build Project from the popup menu to compile all the bootloader sources and link them together into the final executable.

The bootloader program is now ready to be programmed into the internal flash memory of the STM32F407ZG microcontroller. Make sure the Olimex STM32-E407 board is connected to your PC via a ST-LINK/V2 debugger interface. Next, select Run → Debug from the menu to flash the bootloader program. This will launch the Debug perspective in Eclipse. Once done, you can start the bootloader program by selecting Run → Resume from the menu.

Alternatively, you can use your favorite programmer to flash the bootloader using one of the following files, depending on what file type your programmer supports:

• \Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\Boot\Debug\openblt_olimex_stm32e407.elf
• \Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\Boot\Debug\openblt_olimex_stm32e407.srec

1. Set the project as the active project in Eclipse. This is achieved by clicking the Prog project in the Project Explorer to select it.
2. Delete the file \Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\Prog\Debug\demoprog_olimex_stm32e407.elf.
3. Next, right-click the Prog project in the Project Explorer and select Refresh from the popup menu.
4. Finally, right-click the Prog project in the Project Explorer and select Build Project from the popup menu to compile all the user program sources and link them together into the final executable.

The output file is

• \Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\Prog\Debug\demoprog_olimex_stm32e407.srec

To download the demo program \Target\Demo\ARMCM4_STM32F4_Olimex_STM32E407_CubeIDE\Prog\Debug\demoprog_olimex_stm32e407.srec using the bootloader, follow the instructions in the following links, depending on the communication interface you intend to use:

• Firmware updates using the RS232 communication interface
• Firmware updates using the CAN communication interface
• Firmware updates from SD-card