Input/output controller

Claim 2

The I/O controller as claimed in claim 1, characterized in that said decision means (24) gives a decision about abnormality based on a hard error signal from said I/O unit (31), after a data is written in said spare I/O unit (31).

Claim 3

The I/O controller as claimed in claim 1, characterized in that said decision means (24) gives a decision about abnormality based on a read error signal from said spare I/O unit (31) after carrying out a write operation on said spare I/O unit (31) and carrying out a read operation.

Claim 4

The I/O controller as claimed in claim 1, characterized in that said decision means (24) gives a decision about abnormality after carrying out a seek operation on said spare I/O unit (31), based on a hard error signal from said I/O unit (31).

Claim 5

The I/O controller as claimed in claim 1, characterized in that said decision means (24) gives a decision about abnormality after carrying out a seek operation on said I/O unit (30), based on a hard error signal from said I/O unit (30).

Claim 6

The I/O controller as claimed in claim 1, characterized by further comprising a patrol timer register (27) for counting said time interval not in use for an operation, and characterized in that said decision means (23) gives a decision about abnormality in said selected I/O unit (30) or spare I/O unit (31) after a count in said patrol timer register (27) reaches a specified value.

Claim 7

The I/O controller as claimed in any of claims 1 to 5, characterized in that said I/O controller comprises a plurality of said master unit interface controllers (21), said checking means (22), said controlling means (23), said decision means (24), said preventive maintenance information storage registers (25), and said subordinate unit interface controllers (26), which are placed in a shared connection with a plurality of logical devices, one logical device consisting of said plurality of I/O units (30) and one spare I/O unit (31), and which perform a selection control over any one of the plurality of logical devices based on a command from said master unit (10).

Claim 8

The I/O controller as claimed in claim 1 or claim 6, characterized in that said decision means (24) allows said spare I/O unit (31) to carry out a write operation of data when the first seek operation is performed and completed in a normal manner; allows said I/O unit (31) to carry out the second seek operation when the write operation of said data is completed in a normal manner and to perform a read operation of said data; and gives a decision of abnormality when an error signal is input from said spare I/O unit (31) in any of said first seek operation, write operation, second seek operation, or read operation.

Claim 9

The I/O controller comprising a subordinate unit interface controller (63) connected to a plurality of logical devices, which are subordinate units, one logical device consisting of a plurality of data disk drives (700 - 707), one parity disk drive (708) and one spare disk drive (709), a channel interface controller (61) which receives a command issued from a master unit (50) to any one of said plurality of logical devices, a synchronous rotation controller (66) which puts under synchronous rotation control the plurality of data disk drives (700 - 707), the parity disk drive (708) and the spare disk drive (709), which constitute said plurality of logical devices, via said subordinate unit interface controller (63), an operation controller (62a) which selects said data disk drives and parity disk drive (700 - 708) when these data disk drives and parity disk drive (700 - 708) are normal and are found to contain no hard error or read error, selects the other normal data disk drives and/or parity disk drive and said spare disk drive (709) when an error is found, and controls a read and write operation on said selected disk drives, based on a command input from the master unit (50) via said channel interface controller (61), a decision controller (62b) which decides normality of operation of the data disk drives (700 - 707), the parity disk drive (708) or the spare disk drive (709) belonging to the one logical device selected via said subordinate unit interface controller (63), selection being carried out at a time interval not in use for an operation when said operation controller (62a) is not processing a command input from said master unit (50) via said channel interface controller (61), and a preventive maintenance information storage register (64) which, when said decision controller (62b) gives a decision of abnormality, temporarily stores information about the abnormality in order to submit it later to said master unit (50) later as preventive maintenance information.

Claim 10

The I/O controller as claimed in claim 9, characterized in that said decision controller (62b) gives a decision of abnormality based on a hard error signal from said spare disk drive (709), after carrying out a write operation of data on said spare disk drive (709).

Claim 11

The I/O controller as claimed in claim 9, characterized in that said decision controller (62b) gives a decision of abnormality based on a read error signal from said spare disk drive (709) after carrying out a write operation on said spare disk drive (709) and carrying out a read operation.

Claim 12

The I/O controller as claimed in claim 9, characterized in that said decision controller (62b) gives a decision of error, based on a hard error signal from said spare disk drive (709) after carrying out a seek operation on said spare disk drive (709).

Claim 13

The I/O controller as claimed in claim 9, characterized in that said decision controller (62b) gives said decision on said one selected logical device when a command is executed within a specified time following an execution of a command from said master unit (50).

Claim 14

The I/O controller as claimed in claim 9, characterized in that, when a command is not executed within a specified time after an execution of a command from said master unit (50), said decision controller (62b) gives a decision about abnormality for said one selected logical device, based on the presence or absence of a hard error, after carrying out a patrol seek operation where each head of said data disk drives (700 - 707) and said parity disk drive (708), which constitute said one selected logical device, is moved a specified distance.

Claim 15

The I/O controller as claimed in 9 claim, characterized in that said operation controller (62a) submits information about abnormality stored in said preventive maintenance information storage register (64), to said master unit (50) when there is a command from said master unit (50) to the logical device found to be abnormal.

Claim 16

The I/O controller as claimed in 9, characterized in that said operation controller (62a) comprises a processor (621), a controlled storage (622) which stores instruction codes for said processor (621) and is used as a firmware control table, a data transfer controller (628) which controls data transfer between said channel interface controller (61) and subordinate unit interface controller (62) and creates a parity for transferred data and transfers the parity to said subordinate interface controller (63), a system timer reset register (623), a timer register for monitoring the operating time (624), a seek address register (625) which specifies a track address on which to perform a seek operation, a logical device address register (626) which specifies a logical device to be selected, and an error-detecting flag register which indicates the presence or absence of abnormality in said each disk drive (700 - 709).

Claim 17

The I/O controller as claimed in 9, characterized in that said subordinate unit interface controller (63) consists of drive-specific disk controllers (630 - 639) which interface independently with each of said data disk drives (700 - 707), said parity disk drive (708) and said spare disk drive (709).

Claim 18

The I/O controller as claimed in claim 9, characterized by further comprising a patrol timer register (65) for counting said time interval not in use for an operation, and characterized in that said decision controller (62b) gives a decision of abnormality of said selected data disk drives, said parity disk drive, or said spare disk drive (709) after the count of a said patrol timer register (65) has reached a specified value.

Claim 19

The I/O controller as claimed in any of claims 9 to 18, characterized in that said I/O controller comprises a plurality of said channel interface controllers (11), said operation controllers (62a), said decision controllers (62b), said preventive maintenance information storage registers (64) for storing, said subordinate interface controllers (63) and said synchronous rotational controllers (66), which are put in a shared connection with a plurality of logical devices, one logical device consisting of said data disk drives, parity disk drive (700 - 708) and spare I/O unit (709), and which perform a selection control over any one of the plurality of logical devices based on a command from said master unit (50).

Claim 20

The I/O controller as claimed in claim 9 characterized in that said decision controller (62b) allows said spare disk drive (709) to carry out a write operation of data when the first seek operation, where a head is moved a specified distance, is performed and completed in a normal manner; allows said spare disk drive (709) to carry out the second seek operation when the write operation of said data is completed in a normal manner and to perform a read operation of said data; and gives a decision of abnormality when an error signal is input from said spare disk drive (709) in any of said first seek operation, write operation, second seek operation, or read operation.

Claim 21

The I/O controller as claimed in claim 20, characterized in that said decision controller (62b) divides the recordable side of a spare disk of said spare disk drive (709) into a plurality of zones, and allows said read and write operation of data to be carried out on representative tracks of the zones.

Claim 22

The I/O controller as claimed in 21, characterized in that said read and write operation of data on said representative tracks of zones, is carried out on each zone sequentially in a such a way that the operation is switched in a cyclic way.

Claim 23

The I/O controller characterized in that it comprises a subordinate interface controller (63) to which a plurality of logical devices is connected as subordinate units, one logical device consisting of a plurality of data disk drives (700 - 707), one parity disk drive (708), one spare disk drive (709), a channel interface controller (61) which receives a command issued from a master unit (50) to any one of said plurality of logical devices, a synchronous rotation controller (66) which puts under synchronous rotation control the plurality of data disk drives (700 - 707), the parity disk drive (708) and the spare disk drive (709), via said subordinate unit interface controller (63), an operation controller (62a) which selects said data disk drives and parity disk drive (700 - 708) when these data disk drives and parity disk drive (700 - 708) are normal and are found to contain no hard error or read error, selects the other normal data disk drives and/or parity disk drive and said spare disk drive (709) when any error is found, and controls a read and write operation on said selected disk drives, based on a command input from the master unit (50) via said channel interface controller (61), and power supply means for supplying power to each of the data disk drives, the parity disk drive or the spare disk drive, which belong to the logical device selected via said subordinate unit interface controller (63), and for always maintaining each disk drive (700 - 709) in ready status.

Claim 24

The I/O controller characterized in that it comprises a subordinate unit interface controller (63) to which a plurality of logical devices are connected as subordinate units, one logical device consisting of a plurality of data disk drives (700 - 707), one parity disk drive (708), and one spare disk drive (709), a channel interface controller which receives a command issued from a master unit (50) to any one of a plurality of logical devices, a synchronous rotation controller (66) which puts under synchronous rotation control said plurality of data disks (700 - 707), parity disk drive (708) and spare disk drive (709), which constitute said plurality of logical devices, via said subordinate unit interface controller (63), an operation controller (62a) which selects said data disk drives and parity disk drive (700 - 708) when these data disk drives and parity disk drive (700 - 708) are normal and are found to contain no hard error or read error, selects the other normal data disk drives and/or parity disk drive and said spare disk drive (709) when any error is found, and controls a read and write operation on said selected disk drives, based on a command input from the master unit (50) via said channel interface controller (61), a decision controller (62b) which decision normality of operation of the data disk drives (700 - 707), the parity disk drive (708) or the spare disk drive (709), which belong to the one logical devices selected via said subordinate unit interface controller (63), selection being carried out at a time interval not in use for an operation when said operation controller (62a) is not processing a command input from said master unit (50) via said channel interface controller (61), power supply means for supplying power to each of the data disk drives, the parity disk drive or the spare disk drive, which belong to the logical device selected via said subordinate unit interface controller (63), and for always maintaining each disk drive (700 - 709) in ready status, and a preventive maintenance information storage register (64) for temporarily storing information about an abnormality in order to submit it later to said master unit (50) as preventive maintenance information, when a decision of abnormality is given by said decision controller (62b).

Claim 25

The I/O controller as claimed in claim 24, characterized in that said decision controller (62b) gives a decision about abnormality based on a hard error signal from said spare disk drive (709), after carrying out a write operation of data on said spare disk drive (709).

Claim 26

The I/O controller as claimed in claim 24, characterized in that said decision controller (62b) give a decision about abnormality based on a read error signal from said spare disk drive (709), after carrying out a write operation of data on said spare disk drive (709) and carrying out a read operation.

Claim 27

The I/O controller as claimed in claim 24,characterized in that said decision controller (62b) gives a decision about abnormality based on a hard error signal from said spare disk drive (709), after carrying out a seek operation of data on said spare disk drive (709).

Claim 28

The I/O controller as claimed in 24, characterized in that said decision controller (62b) gives said decision when a command is executed on said one selected logical device within a specified time following the execution of a command from said master unit (50).

Claim 29

The I/O controller as claimed in claim 24, characterized in that said decision controller (62b) gives a decision about abnormality based on a hard error, after carrying out a patrol seek operation on said selected one logical device, wherein each head of said data disk drives (700 - 707) and parity disk drive (709), which belong to said selected one logical device, is moved a specified distance, a patrol seek operation being carried out when a command is not executed within a specified time following an execution of a command from said master unit (50).

Claim 30

The I/O controller as claimed in claim 24, characterized in that said decision controller (62b) allows said spare disk drive (709) to carry out a write operation of data when the first seek operation, wherein a head is moved a specified distance, is carried out and completed in a normal manner; allows said spare disk drive (709) to carry out the second seek operation when a write operation of said data is completed in a normal manner and to carry out a read operation of said data; and gives a decision of abnormality when an error signal is input from said spare disk drive (709) in any of said first seek operation, write operation, second seek operation, or read operation.