An electronic processing device including a memory and a Micro Control Unit (MCU) is provided. The memory includes a first memory block and a second memory block. The MCU executes first program code stored in the first memory block to write an update program code into the second memory block, and remaps a base address for a reboot of the electronic processing device from the first memory block to the second memory block in response to successfully writing the update program code into the second memory block. After that, the MCU triggers the reboot of the electronic processing device to execute the update program code stored in the second memory block.