Method for performing firmware update in electronic device and micro control unit equipped with firmware update function

A micro control unit equipped with a firmware update function, the micro control unit comprising:

• a core circuit, arranged to control operations of the micro control unit;
• and
• a non-volatile memory, coupled to the core circuit, arranged to store information, wherein memory space of the non-volatile memory comprises a main function procedure region and an upgrade guiding procedure region, for storing a main function procedure and an upgrade guiding procedure, respectively;
• wherein:
• after system reset of the micro control unit, the core circuit executes the upgrade guiding procedure in the upgrade guiding procedure region by default to start controlling upgrade of the main function procedure in the main function procedure region;
• the core circuit checks whether upgrade request information exists, in order to generate a first checking result, wherein the first checking result indicates that the upgrade request information exists;
• in response to the upgrade request information, the core circuit performs firmware update on multiple sub-regions of the main function procedure region, respectively, to generate an updated main function procedure;
• the core circuit performs at least one checking operation to generate at least one checking result;
• and
• in response to the at least one checking result, the core circuit starts executing the updated main function procedure in the main function procedure region.