Boot mode description

Preface

The Core-1109-JD4 is installed with the Linux operating system by
default. If users want to run other operating systems, they need to
use the corresponding firmware to program to the mainboard.

Core-1109-JD4 has a flexible startup mode. Generally, the
Core-1109-JD4 development board will not turn brick unless the
hardware is damaged.

If the accident appeared in the process of upgrading, bootloader
damage, leading to unable to upgrade again, while still can enter
"MaskRom" mode to repair.

How to get the Firmwares

Firmware download link

Upgrade method

Core-1109-JD4 supports firmware update through the following two
methods:

Upgrade the firmware via USB cable<br><br>     Use the USB cable to
connect the mainboard to the computer, and use the upgrade tool to
program the firmware to the mainboard.<br><br>

Upgrade the firmware via SD card<br><br>    Use the upgrade card
creation tool to make the MicroSD card(Suggest using a card with a
capacity of 32GB or less) as an upgrade card, insert the upgrade card
into the mainboard, power on, and the machine will automatically
perform the upgrade.

Boot media

Core-1109-JD4 loads the system from the following memory:

eMMC interface

SDMMC interface

Boot mode

Core-1109-JD4 has three startup modes:

Normal mode

Loader mode

MaskRom mode

Normal mode

Normal mode is the Normal startup process. Each component loads in
turn and enters the system normally.

Loader mode

In Loader mode, the bootloader will enter the upgrade state, waiting
for the host command for firmware upgrade, etc.

MaskRom mode

MaskRom mode is used for system repair when the bootloader is damaged.

Under normal circumstances, it is not necessary to enter "MaskRom
mode". Only when the bootloader verification fails (IDB block cannot
be read, or the bootloader is damaged), the BootRom code will enter
"MaskRom mode". At this time, the BootRom code waits for the host to
transmit the bootloader code through the USB interface, load and run
it.

Forcibly enter MaskRom mode, please refer to the chapter MaskRom Mode.