Bootloader only DFU failed.

RE: Bootloader only DFU failed.

Einar Thorsrud — Wed, 25 Jul 2018 13:01:22 GMT

No, there is no tag in this question which indicate the SDK version. In any case it seems you have found a mismatch between the documentation and implementation in SDK 14.2. You can see that from line 339-347 in dfu_req_handling.c, where the bootloader and SoftDevice is required to have a higher version number:

            case DFU_FW_TYPE_BOOTLOADER:            // fall through
            case DFU_FW_TYPE_SOFTDEVICE_BOOTLOADER:
                // updating the bootloader is stricter. There must be an increase in version number
                if (p_init->fw_version <= fw_version)
                {
                    NRF_LOG_ERROR("BL FW version too low");
                    return ext_error_set(NRF_DFU_EXT_ERROR_FW_VERSION_FAILURE);
                }
                break;

You can allow upgrading bootloader to the same version by moving line 339 (case DFU_FW_TYPE_BOOTLOADER:) to above line 331.

RE: Bootloader only DFU failed.

schef — Wed, 25 Jul 2018 11:23:26 GMT

I use SDK 14.1. Can't you see it in the tags?

RE: Bootloader only DFU failed.

Einar Thorsrud — Wed, 25 Jul 2018 10:28:19 GMT

Hi,

Which SDK version are you using?

Referring to the SDK 15.0.0 implementation, you can see that the implementation of fw_version_ok() should same version to be upgraded for the bootloader (anything not application or SoftDevice):

static bool fw_version_ok(dfu_init_command_t const * p_init)
{
    ASSERT(p_init != NULL);
    ASSERT(p_init->has_fw_version);

    if (  (p_init->type == DFU_FW_TYPE_APPLICATION)
       || (p_init->type == DFU_FW_TYPE_SOFTDEVICE))
    {
        return ((p_init->fw_version >= s_dfu_settings.app_version) || !NRF_DFU_APP_DOWNGRADE_PREVENTION);
    }
    else
    {
        return  (p_init->fw_version > s_dfu_settings.bootloader_version);
    }
}