RE: Bootloader usage for multiple applications switch

Hung Bui — Fri, 21 Sep 2018 08:49:52 GMT

Another similar case, with I think more detailed solution, covering with and without SD: devzone.nordicsemi.com/.../can-t-jump-to-a-custom-app-location-using-nrf_bootloader_app_start-with-sdk-v15

RE: Bootloader usage for multiple applications switch

bjorn-spockeli — Wed, 06 Jun 2018 12:55:50 GMT

Hi Jonnavittula,

jumping between multiple applications is not something we support out of the box, but it is possible to modify the bootlaoder to do so.

The bootloader jumps to the location passed in the nrf_bootloader_app_start_final() call in nrf_bootloader_app_start() in nrf_bootloader_app_start.c. You can modify this address so that the bootlaoder jumps to another location, i.e. another app. Note: you will also have to modify nrf_dfu_mbr_irq_forward_address_set() so that the interrupts are forwarded to the correct location.

void nrf_bootloader_app_start(void)
{
    uint32_t start_addr = MBR_SIZE; // Always boot from end of MBR. If a SoftDevice is present, it will boot the app.
    NRF_LOG_DEBUG("Running nrf_bootloader_app_start with address: 0x%08x", start_addr);
    uint32_t err_code;

    // Disable and clear interrupts
    // Notice that this disables only 'external' interrupts (positive IRQn).
    NRF_LOG_DEBUG("Disabling interrupts. NVIC->ICER[0]: 0x%x", NVIC->ICER[0]);

    NVIC->ICER[0]=0xFFFFFFFF;
    NVIC->ICPR[0]=0xFFFFFFFF;
#if defined(__NRF_NVIC_ISER_COUNT) && __NRF_NVIC_ISER_COUNT == 2
    NVIC->ICER[1]=0xFFFFFFFF;
    NVIC->ICPR[1]=0xFFFFFFFF;
#endif

    err_code = nrf_dfu_mbr_irq_forward_address_set();
    if (err_code != NRF_SUCCESS)
    {
        NRF_LOG_ERROR("Failed running nrf_dfu_mbr_irq_forward_address_set()");
    }

    NRF_LOG_FLUSH();
    nrf_bootloader_app_start_final(start_addr);
}

Best regards

Bjørn