nRF52832 FOTA (Firmware update using BLE)

[jju]

Hi,

We have developed firmware for a custom broad using the nRF52832 with 512kB flash, and our firmware currently uses 48.5% of the flash.

We are using Zephyr and version 2.6.1 of the toolchain.

The bootloader, we can find in the documentation examples uses dual-slot, so there has to be flash space for the 2x (bootloader+firmware).

Since our current firmware, which is not complete yet, uses 48.5% of the flash, I predict we will run into trouble with a full flash.

Is it possible to just have a BLE bootloader and the firmware, so if anything goes wrong, it will just start in the bootloader ?

Best regards

Jakob

[Menon]

Hello,

jju said:

Okay, but is it then possible to use an external flash with the nRF52832 FOTA nRF sdk ?

Yes it is possible to use an external flash for achieving OTA DFU. To update via BLE DFU with SPI external flash on nRF52832, you should make sure the SPI external flash works as expected at first. Here is a sample. You can take a look at the settings: nrf52840dk_nrf52840_spi.conf and nrf52840dk_nrf52840_spi.overlay and adopt them for your nRF52832 custom board. 

• Enable mcuboot, you can use sysbuild_fota.conf to include sysbuild configs. 
• These external SPI settings are for the app configuration. 
• The board overlay file looks like this for the app. 
• These external SPI setting (under sysbuild/mcuboot) are for the mcuboot.
• The board overlay file looks like this for the mcuboot. 

As a starting point see the the Quick start guide and this Bootloaders and DFU/FOTA course.

Kind Regards,

Abhijith