I'm having trouble enabling BLE DFU on my firmware for the nRF52833. I'm following the steps from the Dev Academy course - FOTA over Bluetooth Low Energy. After adding the following to my prj.conf file:
# Enable FOTA over Bluetooth LE CONFIG_BOOTLOADER_MCUBOOT=y CONFIG_NCS_SAMPLE_MCUMGR_BT_OTA_DFU=y
And in the sysbuild.conf file:
# Enable MCUboot SB_CONFIG_BOOTLOADER_MCUBOOT=y
I get the following overflow error:
/opt/nordic/ncs/toolchains/f8037e9b83/opt/zephyr-sdk/arm-zephyr-eabi/bin/../lib/gcc/arm-zephyr-eabi/12.2.0/../../../../arm-zephyr-eabi/bin/ld.bfd: zephyr/zephyr_pre0.elf section `rodata' will not fit in region `FLASH' /opt/nordic/ncs/toolchains/f8037e9b83/opt/zephyr-sdk/arm-zephyr-eabi/bin/../lib/gcc/arm-zephyr-eabi/12.2.0/../../../../arm-zephyr-eabi/bin/ld.bfd: region `FLASH' overflowed by 32788 bytes collect2: error: ld returned 1 exit status
However, without the BLE OTA features, my used size region is well under what's available. I understand that MCUBoot will double the flash sized used, but even still, I should be under what's available.
Memory region Used Size Region Size %age Used
FLASH: 241768 B 488 KB 48.38%
RAM: 52864 B 128 KB 40.33%
IDT_LIST: 0 GB 32 KB 0.00%
I have tried removing some features in my prj.conf file, and following some recommendations in the memory footprint optimizations documentation, but the value reported in my overflow does not seem to change. Why is that? What can I try next?