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2 years, 7 months ago.
Default bootloader on STM32L432KC
Dear all, I have project based on Nucleo STM32L432KC with 256k FLASH. My application is about 80k. I am using the last 3 pages of FLASH memory as EEPROM to save some configuration data. The main connection with my own application on PC is by USB (as a virtual COM port) - on the baseboard is a FTDI chip FT230XS which is connected to the Nucleo on pins PB6 (Tx) and PB7 (Rx). Now I need to add some possibility to update the firmware in Nucleo from my PC application – simply upload the new bin file. It means that there is necessary to implement some bootloader.
I am a bit new in programing and I see that bootloader is above my strength now. I have few questions: - I have found that in STM32L432KC is some bootloader available as a default https://www.st.com/content/ccc/resource/technical/document/application_note/51/5f/03/1e/bd/9b/45/be/CD00264342.pdf/files/CD00264342.pdf/jcr:content/translations/en.CD00264342.pdf
- Is it true or not? - If yes is realy also available on pins PB6 and PB7? (I think no, because there is default I2C)
I have one idea: For update I will use the available SW like FLASHER-STM32 (not my application) and default built-in bootloader. But if I see right in datasheet on my pins PB6, PB7 is default I2C bootloader not UART. Do you have any idea how to solve it?
Thank you very much for your help. I will be thankful for every idea.
Best regards Lukas
2 years, 7 months ago.
- STM32 microcontrollers come with built-in bootloader that is programmed during production - see Application Note AN2606.
- Table 6 - Boot modes (chapter 2.6, Boot configuration) in the Reference manual, shows how to select system memory as boot area (i.e. how to start the bootloader on reset). Based on that information it seems that you'll need to disconnect the BOOT0 pin from GND by opening the solder bridge SB12 (see Figure 10, MCU, in the User Manual for STM32 Nucleo-32 boards) before each software update and then close it once you have finished.
- I would recommend to update your NUCLEO board either using MBED's drag and drop (i.e. copy and paste) feature, as you did so far, or you can use the STM32 ST-LINK utility for flashing.