Patent ID: 8694717

Claim:
An electronic device with program update functions, comprising: a first integrated circuit chip comprising an interface circuit interfacing with and directly connected to an external recording medium, a compression decoder decoding compressed data received from the external recording medium through the interface circuit, a mask ROM storing a first program to control the compression decoder, and a first CPU executing the first program stored in the mask ROM, the mask ROM and the first CPU operating as part of a ROM correction circuit correcting the first program stored in the mask ROM based on update information of the first program stored in the external recording medium; and a second integrated circuit chip comprising an electrically erasable programmable nonvolatile memory and a second CPU executing a second program stored in the nonvolatile memory, the second integrated circuit chip being formed as one chip, and the second integrated circuit chip controlling the entire electronic device, wherein the first integrated circuit chip is configured to transmit data to and receive data from the second integrated circuit chip and is configured to write the update information received from the external recording medium through the interface circuit into the nonvolatile memory, the ROM correction circuit is configured to update the first program based on the update information received from the nonvolatile memory of the second integrated circuit chip when the first CPU executes the first program, and the external recording medium stores only the update information and does not store a whole program that controls the compression decoder.