Receiving a reset signal directly from an ATA or ATAPI bus of a host computer without passing through an interface processing unit for termination of a half halted state

摘要

The present invention relates to an information processing apparatus wherein a device connected to a host computer enters a sleep mode in accordance with a judgment made by the device itself, and the device is restored to its original operating state by a hardware reset signal received from the host computer. To put it in detail, if no data is exchanged through an ATAPI command data I/F for at least a predetermined period of time, a CPU of the device outputs a sleep mode to a clock generator and a drive power supply block to put the device in a sleep mode. When a CPU of the host computer outputs a HRST signal in this mode to the device through an ATAPI bus to restore the device from the sleep mode, an IRQ signal reception unit of the CPU employed in the device receives this HRST signal. Receiving the HRST signal, the CPU of the device issues a command requesting restoration from the sleep mode to the clock generator and the drive power supply block. The present invention can be applied to an optical disc drive.