Replacement device, information processing method, and information processing device

An information processing method comprising:

• a first determination step of determining whether or not a processor has performed access of instruction fetch to a predetermined address of a nonvolatile memory on the nonvolatile memory used by the processor as a boot device;
• a second determination step of determining whether or not data acquired by the access of the instruction fetch from the nonvolatile memory matches identification information indicating that program data has been written in the nonvolatile memory when it is determined, in the first determination step, that the access of the instruction fetch to the predetermined address has been performed;
• and
• a replacement step of replacing the data with one of a first instruction to change a program counter in the processor and a second instruction not to change the program counter in accordance with a determination result of the second determination step, and outputs one of the first instruction and the second instruction to the processor.

An information processing method comprising:

• a first writing step of writing program data to an address of a nonvolatile memory, the address not overlapping a predetermined address for a processor using the nonvolatile memory as a boot device to access the nonvolatile memory for first performing instruction fetch after reset release;
• and
• a second writing step of writing identification information indicating that the program data has been written in the nonvolatile memory to the predetermined address of the nonvolatile memory after the program data is written in the first writing step,
• a hardware device executing the first writing step and the second writing step;
• wherein the first writing step includes:
• first writing processing of writing the program data to the nonvolatile memory;
• and
• first verification processing for the first writing processing,
• wherein processing shifts to the second writing step when the first verification processing succeeds, the first writing processing is re-executed when the first verification processing fails, the second writing step is skipped when re-execution of the first writing processing is repeated up to a number of times of an upper limit, and processing of writing to the nonvolatile memory is ended with an error.

An information processing device comprising:

• a processor;
• and
• a nonvolatile memory used by the processor as a boot device,
• wherein, in the nonvolatile memory, writing of first identification information indicating that a program data to be executed by the processor has been written in the nonvolatile memory to a first predetermined address which the processor first performs instruction fetch after reset release and writing of the program data to an address not overlapping the first predetermined address are executed after the nonvolatile memory is mounted;
• wherein the information processing device further comprising a first replacement processing unit including:
• a first determination unit that determines whether or not the processor has performed access of instruction fetch to the first predetermined address of the nonvolatile memory on the nonvolatile memory;
• a second determination unit that determines whether or not data acquired by the access of the instruction fetch from the nonvolatile memory matches the first identification information when the first determination unit determines that the access of the instruction fetch to the first predetermined address has been performed;
• and
• a first replacement unit that replaces the data with one of a first instruction to change a program counter in the processor and a second instruction not to change the program counter in accordance with a determination result from the second determination unit, and outputs one of the first instruction and the second instruction to the processor.