Embedded device and program updating method

An embedded device comprising:

• a network input/output unit receiving update information via a network;
• a first nonvolatile memory having a plurality of planes from/to which data can be read/written independently;
• a CPU executing a program disposed in the first nonvolatile memory;
• and
• a first address translator performing address translation by using an address translation table included in update information received by the network input/output unit,
• wherein in the first nonvolatile memory, a default program is disposed in a first plane and a differential program with respect to the default program, included in update information received by the network input/output unit is disposed in a second plane,
• wherein when an address obtained by decoding an instruction by the CPU is an address corresponding to a change part in the default program, the first address translator translates the address to an address in which the differential program is disposed, and
• wherein the CPU executes the differential program in accordance with the address translated by the first address translator.