Data read apparatus, data read method, and storage medium storing data read program

A non-transitory computer readable storage medium having stored therein a program for controlling a processor of an electric device which includes a nonvolatile memory comprising a plurality of blocks, each of the blocks including an area storing block information, in which a position of a next block is written, and file management information, and an area storing actual data, a volatile memory, and a power-on circuit configured to turn on supply of power to the nonvolatile memory and the volatile memory, the program causing the processor to execute:

• (1) read out the block information stored in each of the blocks of the nonvolatile memory, or the block information and the file management information, when the supply of power was turned on by the power-on circuit, and
• (2) register the read-out block information, or the block information and the file management information, in the volatile memory as file position information;
• (3) read out a series of actual data of a file associated with the file management information stored in the nonvolatile memory, by referring to the file position information registered in the volatile memory;
• (4) successively write and manage, each time an update of the file occurs, the file management information after the update in of a plurality of file management information areas that are sequentially ordered in a certain block of the nonvolatile memory to store the file management information;
• (5) count-up, when updating the file, so that a number of times that the file has been updated is stored in an update number management area that is set in the certain block of the non-volatile memory to store the number of times the file has been updated;
• (6) determine which file management information area is currently being used based on the number of times the file has been updated which is stored in the update number management area;
• and
• (7) read out a series of actual data associated with the file management information stored in the nonvolatile memory, by referring to the file position information registered in the volatile memory.

A data read method of an electric device which includes a nonvolatile memory comprising a plurality of blocks, each of the blocks including an area storing block information, in which a position of a next block is written, and file management information, and an area storing actual data, a volatile memory, and a power-on circuit configured to turn on supply of power to the nonvolatile memory and the volatile memory, the method comprising:

• (1) reading out the block information stored in each of the blocks of the nonvolatile memory, or the block information and the file management information, when the supply of power was turned on by the power-on circuit, and
• (2) registering the read-out block information, or the block information and the file management information, in the volatile memory as file position information;
• (3) reading out a series of actual data of a file associated with the file management information stored in the nonvolatile memory, by referring to the file position information registered in the volatile memory;
• (4) successively writing and managing, each time an update of the file occurs, the file management information after the update in of a plurality of file management information areas that are sequentially ordered in a certain block of the nonvolatile memory to store the file management information;
• (5) counting-up, when updating the file, so that a number of times that the file has been updated is stored in an update number management area that is set in the certain block of the non-volatile memory to store the number of times the file has been updated;
• (6) determining which file management information area is currently being used based on the number of times the file has been updated which is stored in the update number management area;
• and
• (7) reading out a series of actual data associated with the file management information stored in the nonvolatile memory, by referring to the file position information registered in the volatile memory.