NRF52840 and STM32 (firmware update)

RE: NRF52840 and STM32 (firmware update)

Shivaprasad Desai — Mon, 07 Mar 2022 14:58:31 GMT

Hi Vidar,

I went through the details you mentioned here, I had one query related to it -> does it mean that I have to modify the bootloader code or is there something similar that can be done in the dfu client code.

Thanks in advance.

Kindly,

Shivaprasad.

RE: NRF52840 and STM32 (firmware update)

Vasa — Thu, 07 Nov 2019 18:00:56 GMT

Thanks fo the reply, but what will happen if STM firmware is bigger than bank1 size, will nrf reject to receive this file? Will nrf inform that it is impossible to receive this file?
IMPORTANT! Is there possiblity to receive STM firmware part-by-part and send these parts to STM (on the fly)?

RE: NRF52840 and STM32 (firmware update)

Vidar Berg — Mon, 04 Nov 2019 10:42:16 GMT

The new image is placed in the free area above the application which we call bank 1, see Memory layout and Dual-bank updates. And you may use nrf_dfu_bank1_start_addr() to get the start address of bank 1.

The image transfer to the ST part will require a custom implementation as we don't have a reference implementation of this. I suggest using the app_activate() function to get an idea of how the image can read from bank 1 and copied to target.

RE: NRF52840 and STM32 (firmware update)

Vasa — Sun, 03 Nov 2019 08:07:50 GMT

I managed to send stm32 .hex (FW intended for ST) over nrf dfu service and check the flag .bank_1.bank_code it is definitely changed to NRF_DFU_BANK_VALID_EXT_APP, but anyway it is not obvious for me how to transfer ST firmware to the ST chip? Where the ST FW located from physical point of view? Is there any example how to do this in a proper way?

SDK 15.3

Softdevice S140

RE: NRF52840 and STM32 (firmware update)

Vidar Berg — Thu, 31 Oct 2019 08:38:50 GMT

The bootloader verifies the integrity of the received image in nrf_dfu_validation.c::postvalidate() and updates the .bank_1.bank_code flag to NRF_DFU_BANK_VALID_EXT_APP if it passes the check. Once the bank code is updated, you know the ext. App has been validated, and you can start transferring it to the ST chip.

nrf_bootloader_fw_activation.c::app_activate() shows how internal app images are copied from bank 1 to bank 0. You may use this as a reference. Except that your function needs to copy it from bank 1 to the ST.

RE: NRF52840 and STM32 (firmware update)

Vasa — Wed, 30 Oct 2019 16:24:04 GMT

Thanks for the reply, is it possible to verify that the ST FW received before sending it to the target? I mean how to read ST .hex, were it is stored?

RE: NRF52840 and STM32 (firmware update)

Vidar Berg — Wed, 30 Oct 2019 12:53:08 GMT

Hi,

You can receive app images intended for external targets if you enable the NRF_DFU_SUPPORTS_EXTERNAL_APP config option in the bootloader project, and use the -----external-app flag when you create the DFU distribution package. The image will be stored to bank 1. So the remaining task will be to forward it to the ST chip.

Screenshot from the nrfutil help menu (nrfutil pkg generate --help)

Regards,

Vidar