Experts teach you how to write STM32 bootloader

Today I will teach you how to write the bootloader for STM32 . In fact, the main things to do when writing the bootloader are as follows:

1. Select the memory address for your bootloader program, because the STM32 memory FLASH storage program code space is 512K and needs to be divided.

2. If you need to use JTAG online debugging, you need to configure the area:

3. Choose the appropriate storage space for your user program:

At the same time, configure the online debugging area:

4. The basic process of writing the bootloader program is as follows:

1) Check whether there is a flag that needs to be updated, which can be customized by the user. For example, read the byte stored in a certain position of the flash as a flag.

2) If an update is required, call the STM32 FLASH program shoe polishing user code part.

3) Write the new bin file (that is, the binary file is burned directly into it, the hex file generated by Keil needs to be converted into a bin file, and then stored in the external expansion flash) into the FLASH that comes with the STM32 . Remember that it needs to be consistent with the user code storage area set above.

4) After the update is successful, jump to the user program.

5. The user program needs to pay attention to the need to reset the interrupt vector table before the program runs, that is: NVIC_SetVectorTable().

6. When using the STM32 built-in burning software for burning, the items need to be modified as follows:

1) Open the map folder in the target file after installation. The STM32 we use is 512Kflash, so select STM32_High-density_512K.STmap and decompose it into two STmap files (this file can be opened with Notepad)

In the STmap file, sectors are displayed as 2K pages each, so we only need to go to page 7 for the boot area, and we need to go to page 8 to the end for the user area.

After the modification is completed, when you open the software again, you will find two more flash options. You can choose the code area to be stored here.

Then there is one more thing that needs to be modified: