David C Van Metre
Veterinary in Fort Collins, CO

6493811, Dec 10, 2002

Jan 20, 1999

09/233979

Jerry A. Blades - Broomfield CO
Matthew C. Dewey - Broomfield CO
Bruce A. Thompson - Golden CO
David J. Van Maren - Fort Collins CO
James M. Wilson - Superior CO

Computer Associated Think, Inc. - Islandia NY

G06F 1200

711203, 711202, 711147, 711148, 711 6, 711111, 711112

File operations on files in a peripheral system are controlled by an intelligent controller with a file processor. The files are accessed as if the intelligent controller were an addressable virtual storage space. This is accomplished first by communicating controller commands for the intelligent controller through read/write commands addressed to a Command Region of a virtual storage device. The controller commands set up a Mapped Data Region in the virtual storage device for use in controlling data transfer operations to and from the peripheral system. With the Mapped Data Regions set up, blocks of data are transferred between the host and the intelligent controller in response to read/write commands addressed to the Mapped Data Region of the virtual storage device. In an additional feature of the invention file operations are communicated between host and controller through a device driver at the host and a device emulator at the intelligent controller. If the address in the device write/read command is pointing to the Command Region of the virtual storage device, a Command Region process interprets and implements the controller operation required by the controller command embedded in the device write/read command.

4974189, Nov 27, 1990

Aug 16, 1988

7/232723

Virgil K. Russon - Greeley CO
David J. Van Maren - Fort Collins CO

Hewlett Packard Company - Palo Alto CA

G06F 722

364900

A tape packet assembler/disassembler (TPAD) for a tape drive accumulates host-transmitted records, which may or may not be blocked by the host. The interblock gaps that would ordinarily separate the host-transmitted records now separate packets, resulting in a considerable increase in the efficiency of tape utilization. When the user attempts to modify an existing collection of application records the entire packet containing that collection must first be read to place its content into the TPAD, the revision created in the buffer, and then a revised version of the entire packet written back to the tape. A failure in this process can result in the loss or corruption of data in that part of the packet preceding the revision. This loss can come as a surprise and be unacceptable to the user. To prevent such corruption or loss the TPAD does not attempt to overwrite the original version of the packet receiving the modification until it has successfully written a demonstration packet (equal in content to the revised packet) a safe distance down the tape beyond the packet to be overwritten.

7167951, Jan 23, 2007

Oct 2, 2002

10/263274

Jerry A. Blades - Broomfield CO, US
Matthew C. Dewey - Broomfield CO, US
Bruce A. Thompson - Golden CO, US
David J. Van Maren - Fort Collins CO, US
James M. Wilson - Superior CO, US

Computer Associates Think, Inc. - Islandia NY

G06F 12/00

711114, 711112, 711170

Mass storage system controller apparatus receives requests for access to files in a data storage system and manages access to the files in the data storage system, the data storage system having a plurality of storage devices and the requests being addressed to the data storage system as a single virtual storage device having addressable Command Regions allocated to controller commands and addressable Mapped Data Regions allocated for data storage. The apparatus includes a file system to manage access to files in the data storage system, the file system having a processor acting as a Command Region processor and acting as a Mapped Data Region processor. A disk emulator responds as a disk drive device to write/read commands and passes the write/read commands addressed to Command Regions of the virtual storage device to the Command Region processor, the write/read commands addressed to Command Regions containing controller commands for the file system. The Command Region processor responds to controller commands in the write/read commands and processes the controller commands to control files in the data storage system. The disk emulator responds as a disk drive device to write/read commands and passes write/read commands addressed to a Mapped Data Region of the virtual storage device to the Mapped Data Region processor.

4847619, Jul 11, 1989

Oct 19, 1987

7/109970

Jeff J. Kato - Greeley CO
David W. Ruska - Greeley CO
David J. Van Maren - Fort Collins CO

Hewlett-Packard Company - Palo Alto CA

H03M 746

341106

An adaptive data compression system is reset when performance drops below a predetermined threshold to permit greater compression of long files with evolving distributions of symbol combinations. The compression system uses a resettable dictionary in which initially unassigned codes are strategically assigned to symbol combinations as they are encountered in the data stream. The difference between the bit-lengths of corresponding lengths of the compressor input and output is compared with a value representing a predetermined performance threshold. The dictionary can be reset if the actual performance falls below the performance threshold. The reset can be inhibited while the dictionary is less than half-full to ensure that performance measures are statistically significant. However, if the performance is such that data expansion is occurring, reset is not so delayed.

4891784, Jan 2, 1990

Jan 8, 1988

7/142180

Jeff J. Kato - Greeley CO
David W. Ruska - Greeley CO
David J. Van Maren - Fort Collins CO

Hewlett-Packard Company - Palo Alto CA

G06F 306

364900

A tape packet assembler/disassembler (TPAD) for a tape drive accumulates host-transmitted records, which may or may not be blocked by the host. The accumulated host-transmitted records are combined into packets comprising a data portion made up of data blocks and a trailer portion made up of table entries describing how to disassemble the packet. Host-transmitted commands to write a tape mark are intercepted by the TPAD and replaced by corresponding information in the trailer. Packets are accumulated in a buffer in the TPAD, and are written to the tape drive when the buffer becomes full, or upon a command from the host to reposition the tape, such as rewind. The interblock gaps that would ordinarily separate the host-transmitted records now separate packets, resulting in a considerable increase in the efficiency of tape utilization. The TPAD maintains in the trailer various pointers to assist in forward and back spacing by file and records. It also can automatically and adaptively compress and decompress the user's data.

5298895, Mar 29, 1994

Nov 19, 1991

7/761783

David J. Van Maren - Fort Collins CO

Hewlett-Packard Company - Palo Alto CA

H03M 730

341 51

The present invention provides a method and apparatus for compressing user data and for storing the user data on magnetic tape. The user data is accepted and organized into a plurality of records. The user data is then compressed according to a compression algorithm involving converting at least some of the user data to codewords using a dictionary which is derived from the data. The compressed data is flushed from memory before a new dictionary is created. The user data may be written to magnetic tape after being organized into groups, the groups being independent of the record organization. A codeword indicating the start of a new dictionary is inserted at the beginning of a group and preferably at the beginning of the first record within a group. Records may be further organized into entities. A codeword indicating a flush operation is inserted following each entity and a codeword indicating the start of a new dictionary is inserted at the beginning of the first entity within a group.

5210851, May 11, 1993

Aug 22, 1989

7/396879

Jeff J. Kato - Greeley CO
David W. Ruska - Greeley CO
David J. Van Maren - Fort Collins CO

Hewlett-Packard Company - Palo Alto CA

G06F 306

395425

A tape packet assembler/disassembler (TPAD) for a tape drive accumulates host-transmitted records, which may or may not be blocked by the host. The accumulated host-transmitted records are combined into packets comprising a data portion made up of data blocks and of a trailer portion made up of table entries describing how to disassemble the packet. Host-transmitted commands to write a tape mark are intercepted by the TPAD and replaced by corresponding information in the trailer. Packets are accumulated in a buffer in the TPAD, and are written to the tape drive when the buffer becomes full, or upon a command from the host to reposition the tape, such as rewind. The interblock gaps that would ordinarily separate the host-transmitted records now separate packets, resulting in a considerable increase in the efficiency of tape utilization. The TPAD maintains in the trailer various pointers to assist in forward and back spacing by file and records. It also can automatically and adaptively compress and decompress the user's data.

5280600, Jan 18, 1994

Nov 18, 1991

7/761840

David J. Van Maren - Fort Collins CO
Peter Bramhall - Long Ashton, GB2

Hewlett-Packard Company - Palo Alto CA

G06F 300, G06F 1300

395425

The present invention provides a data storage method for storing compressed user data and associated information on magnetic tape. User data from a host computer is organized into a plurality of records. The user data is then compressed according to a compression algorithm. The compressed data and information related to the data compression (DC) algorithm are then stored on magnetic tape. The DC algorithm information pertains to at least one stored record of compressed data and is stored in a record header field. The DC algorithm information may provide for example, an algorithm number and/or an indicator for starting a data dictionary used for data compression and decompression. The user data may further be organized into groups having a group index for incorporating the DC algorithm information. The data records may be further organized into entities having at least one record. The DC algorithm information associated with an entity is incorporated into the group index of the group in which the entity of records is contained.

4672646, Jun 9, 1987

Sep 16, 1986

6/908051

David J. Van Maren - Fort Collins CO

Hewlett-Packard Company - Palo Alto CA

G11C 700

377 70

A FIFO shift register (100) includes a parallel data in-port (PIN) to each of its cells (101-132) and a means for managing input to determine for each cell whether it is to receive data and, if so, whether through its conventional serial in-port (SIN) or through its parallel in-port. The input manager comprises a bidirectional shift register of input manager cells arranged in one-to-one correspondence with data cells. A one-bit validity indicator stored within a given input manager cell is logically combined with asserted PUSH and PULL signals to determine the source of data for the associated data cell and its immediate successor. This arrangement not only provides greater speed by minimizing bubble-through time, but permits the FIFO shift register to be clocked. This capacity for synchronous operation permits ready VLSI implementation with concomitant advantages in economy, reliability and speed.

5579516, Nov 26, 1996

Dec 15, 1994

8/357575

David J. Van Maren - Fort Collins CO
Jeffrey Dicorpo - Fort Collins CO

Hewlett-Packard Company - Palo Alto CA

G06F 722

395601

A method for storing a set of files on a multiple volume media set supports the ISO/IEC 13346 standard for optical media while minimizing swapping and temporary storage requirements when the multiple volume media set is used in an optical disk autochanger. The method allows the media set (e. g. , optical disks) to be self-describing in accordance with the ISO/IEC 13346 standard. However, when the media set is on-line, the meta-data is separated from the data to optimize on-line performance. The method sequentializes the meta-data of the file set before writing it to the media set to achieve these advantages.