Plural diverse processors for control of a disk apparatus

Claim 2

A control unit of a disk apparatus for exercising at least positioning control of a head of the disk apparatus, control of reading/writing data from/to a disk via the head, and transfer control of data between the disk apparatus and an external device, said control unit comprising: a first microprocessor capable of mainly exercising positioning control of the head and control for reading/writing data from/into the disk without depending upon control exercised by a second microprocessor different from the first microprocessor and in parallel thereto, so as to perform head positioning by using a servo signal recorded on a data recording surface of the disk or perform head positioning by using both a servo signal recorded on a disk face dedicated exclusively to servo signal and a servo signal recorded on a data recording disk surface; a second microprocessor for exercising transfer control of data between the disk apparatus and an external device; a range of clock frequency or instruction execution speed in which said second microprocessor is operable is or lower than a range of clock frequency or instruction execution speed in which said first microprocessor is operable; said first microprocessor having a first interior or exterior type memory for storing information relating to head positioning control and control for reading or writing data from or into the disk; said second microprocessor having a second interior or exterior type memory for storing at least information relating to transfer control of data; and said second memory having a capacity larger than that of said first memory.

Claim 3

A control unit of a disk apparatus according to claim 1, wherein said first microprocessor comprises an analog-to-digital (A/D) converter for converting said servo signal read out as an analog signal from the disk to a digital signal.

Claim 4

A control unit of a disk apparatus according to claim 1, wherein said first microprocessor and said second microprocessor are sealed into substantially one integrated circuit package.

Claim 5

A control unit of a disk apparatus for exercising at least positioning control of a head of the disk apparatus, control of reading/writing data from/to a disk via the head, and transfer control of data between the disk apparatus and an external device, said control unit comprising: a first microprocessor capable of mainly exercising positioning control of the head and control for reading/writing data from/into the disk without depending upon control exercised by a second microprocessor different from the first microprocessor and in parallel thereto, so as to perform head positioning by using a servo signal recorded on a data recording surface of the disk or perform head positioning by using both a servo signal recorded on a disk surface dedicated exclusively to servo signal and a servo signal recorded on a data recording disk face; a second microprocessor for exercising transfer control of data between the disk apparatus and an external device; said first microprocessor having an instruction execution speed larger than that of said second microprocessor; said first microprocessor having a first memory for storing information relating to head positioning control and control for reading or writing data from or into the disk; said second microprocessor having a second memory for storing at least information relating to transfer control of data; and said second memory having a capacity larger than that of said first memory.

Claim 6

A control unit of a disk apparatus for exercising at least positioning control of a head of the disk apparatus, control of reading/writing data from/to a disk via the head, and transfer control of data between the disk apparatus and an external device, said control unit comprising: a first microprocessor capable of mainly exercising positioning control of the head and control for reading/writing data from/into the disk without depending upon control exercised by a second microprocessor different from the first microprocessor and in parallel thereto, so as to perform head positioning by using a servo signal recorded on a data recording surface of the disk or perform head positioning by using both a servo signal recorded on a disk surface dedicated exclusively to servo signal and a servo signal recorded on a data recording disk face; a second microprocessor for exercising transfer control of data between the disk apparatus and an external device; said first microprocessor having an instruction execution speed larger than that of said second microprocessor; said first microprocessor having a first memory for storing information relating to head positioning control and control for reading or writing data from or into the disk; said second microprocessor having a second memory for storing at least information relating to transfer control of data; and said second memory having a capacity larger than that of said first memory.

Claim 7

A control unit of a disk apparatus according to claim 4, wherein said first microprocessor comprises a reduced instruction set computer (RISC), said second microprocessor comprises a complex instruction set computer (CISC), and both chips of said first microprocessor and said second microprocessor are sealed in a single package.

Claim 8

A small-sized magnetic disk apparatus of 2.5 inch form factor size or less including a casing, a head disk assembly, and a control unit mounted on a circuit substrate disposed in the casing, said control unit exercising at least positioning control of a head of the disk apparatus, control of reading/writing data from/to a disk via the head, and transfer control of data between the disk apparatus and an external device, said control unit comprising: a first microprocessor capable of mainly exercising positioning control of the head and control for reading/writing data from/into the disk without depending upon control exercised by a second microprocessor different from the first microprocessor and in parallel thereto, so as to perform head positioning by using a servo signal recorded on a data recording surface of the disk or perform head positioning by using both a servo signal recorded on a disk surface dedicated exclusively to servo signal and a servo signal recorded on a data recording disk face; a second microprocessor for exercising transfer control of data between the disk apparatus and an external device; said first microprocessor having an instruction execution speed equal larger than that of said second microprocessor and control for reading/writing data from/into the disk; said first microprocessor having a first memory for storing information relating to head positioning control; said second microprocessor having a second memory for storing at least information relating to transfer control of data; and said second memory having a capacity larger than that of said first memory.

Claim 9

A small-sized magnetic disk apparatus of 2.5 inch form factor size or less including a casing, a head disk assembly, and a control unit mounted on a circuit substrate disposed in the casing, said control unit exercising at least positioning control of a head of the disk apparatus, control of reading/writing data from/to a disk via the head, and transfer control of data between the disk apparatus and an external device, said control unit comprising: a first microprocessor capable of mainly exercising positioning control of the head and control for reading/writing data from/into the disk without depending upon control exercised by a second microprocessor different from the first microprocessor and in parallel thereto, so as to perform head positioning by using a servo signal recorded on a data recording surface of the disk or perform head positioning by using both a servo signal recorded on a disk surface dedicated exclusively to servo signal and a servo signal recorded on a data recording disk face; a second microprocessor for exercising transfer control of data between the disk apparatus and an external device; said first microprocessor having an instruction execution speed equal larger than that of said second microprocessor and control for reading/writing data from/into the disk; said first microprocessor having a first memory for storing information relating to head positioning control; said second microprocessor having a second memory for storing at least information relating to transfer control of data; and said second memory having a capacity larger than that of said first memory.