Abstract: A data transfer control apparatus applicable to an image forming apparatus according to an embodiment of the invention includes a first storing unit configured to store data, a second storing unit configured to store data, a temporary storing unit configured to temporarily store data transferred from the first storing unit to the second storing unit or from the second storing unit to the first storing unit, and a transfer control unit configured to select, according to a characteristic of transfer data, one transfer processing of first transfer processing for directly transferring the transfer data from the first storing unit to the second storing unit or from the second storing unit to the first storing unit and second transfer processing for indirectly transferring the transfer data from the first storing unit to the second storing unit or from the second storing unit to the first storing unit via the temporary storing unit and control transfer of the transfer data.

Abstract: At the start up of a system, transfer modes an HDD supports are confirmed and the fastest mode is selected from the transfer modes that the system and the HDD support in common. A test transfer of data is performed between the HDD and a memory in the selected transfer mode. In the event of an error, the transfer mode is changed to a transfer mode which is one rank lower in transfer rate than the current mode. Changing of the transfer modes is repeated until no error to occur in the test transfer. A transfer mode in which no error occurs in the test transfer is decided as a mode to be used.

Abstract: When data is transferred between a memory and a hard disk drive, a file transfer control section issues an instruction to a file system by designating an area in the memory, and the file system designates a page memory area in an IDE driver. The IDE driver comprises means for determining whether the memory area designated by the file system is a cache memory or a non-cache memory, and a relay buffer assigned to the non-cache memory. If the memory area designated by the file system is the cache memory, DMA transfer between the hard disk drive and the relay buffer and data transfer between the relay buffer and the designated memory area is performed. If the memory area designated by the file system is the non-cache memory, DMA transfer between the hard disk drive and the designated memory area is performed.