Magnetic disk drive which accesses host RAM
View Patent ↗In a magnetic disk apparatus which is removably mounted or embedded to a host apparatus and intermittently accessed for recording/reproducing data, a RAM contained in the host apparatus is utilized for a portion or entirety of a buffer RAM for use in the intermittent access to accomplish a reduction in size and cost of the magnetic disk apparatus. In addition, the magnetic disk apparatus is controlled to rotate a magnetic disk at a variable rotational speed, and operated at a rotational speed at which the total power consumption is minimized in accordance with the capacity of the utilized buffer RAM and whether an access is made for recording or reproduction, thereby improving a power saving effect.
1. A magnetic disk apparatus removably mounted or embedded to a host apparatus having a RAM, comprising:
a magnetic disk; and
a control mechanism for intermittently accessing said magnetic disk for recording or reproduction using said RAM of said host apparatus as at least a part of a buffer, said control mechanism of said magnetic disk apparatus at least enabling intermittent accessing of said RAM of said host apparatus for recording or reproduction.
2. A magnetic disk apparatus removably mounted or embedded to a host apparatus having a RAM, comprising:
a magnetic disk; and
a control mechanism for intermittently accessing said magnetic disk for recording or reproduction using said RAM of said host apparatus as at least a part of a buffer, said control mechanism of said magnetic disk apparatus at least enabling intermittent accessing of said RAM of said host apparatus for recording or reproduction;
rotational speed determining means for determining a rotational speed of said magnetic disk at which total power consumption of said magnetic disk apparatus is reduced in accordance with at least one of the capacity of said buffer RAM utilized by said control mechanism and an access mode indicative of whether or not said magnetic disk is accessed for recording or reproduction;
driving control means for controlling said magnetic disk to rotate at the rotational speed determined by said rotational speed determining means; and
servo clock extracting means for extracting a servo clock in accordance with the rotational speed at which said magnetic disk is driven by said driving control means.
3. A storage system comprising:
said magnetic disk apparatus according to claim 1 ; and
a host apparatus including an interface for removably mounting said magnetic disk apparatus thereto.
4. A storage system comprising:
said magnetic disk apparatus according to claim 2 ; and
a host apparatus including an interface for removably mounting said magnetic disk apparatus thereto.