Abstract: A disk array system comprises a plurality of controllers, each of which preferably implements a host side of an ATA interface protocol within automated circuitry to control a respective ATA disk drive. Each controller includes a command buffer for storing disk drive commands to be executed by a respective ATA drive, and includes a circuit that prefetches such commands so that a next disk drive command will be available within the command buffer when the disk drive finishes executing a current disk drive command. A delay that commonly occurs when an ATA disk drive retrieves a next disk drive command is thereby reduced or avoided. The disk drive commands are preferably dispatched to the controllers by a microcontroller over a control bus that is separate from a bus used for input/output data transfers.

Abstract: A disk array system comprises a plurality of automated controllers, each of which implements a host side of a standard ATA interface protocol within automated circuitry to control a respective disk drive. Each automated controller preferably includes a command buffer for storing disk drive commands to be executed by a respective ATA drive, and a data buffer that stores I/O data being transferred to or from the ATA disk drive. In a preferred embodiment, the automated controllers are connected by a control bus to a microcontroller that dispatches disk drive commands to the automated controllers in response to I/O requests from a host computer, and are also connected by a second bus to an automated processor. The automated processor transfers I/O data between the automated controllers/ATA disk drives and a host computer, and tracks the completion statuses of pending I/O requests.

Abstract: A disk array system comprises a plurality of automated controllers, each of which implements a host side of a standard ATA interface protocol within automated circuitry to control a respective disk drive. Each automated controller preferably includes a command buffer for storing disk drive commands to be executed by a respective ATA drive, and a data buffer that stores I/O data being transferred to or from the ATA disk drive. In a preferred embodiment, the automated controllers are connected by a control bus to a microcontroller that dispatches disk drive commands to the automated controllers in response to I/O requests from a host computer, and are also connected by a second bus to an automated processor. The automated processor transfers I/O data between the automated controllers/ATA disk drives and a host computer, and tracks the completion statuses of pending I/O requests.

Abstract: A high performance RAID system for a PC comprises a controller card which controls an array of ATA disk drives. The controller card includes an array of automated disk drive controllers, each of which controls one respective disk drive. The disk drive controllers are connected to a microcontroller by a control bus and are connected to an automated coprocessor by a packet-switched bus. The coprocessor accesses system memory and a local buffer. In operation, the disk drive controllers respond to controller commands from the microcontroller by accessing their respective disk drives, and by sending packets to the coprocessor over the packet-switched bus. The packets carry I/O data (in both directions, with the coprocessor filling-in packet payloads on I/O writes), and carry transfer commands and target addresses that are used by the coprocessor to access the buffer and system memory.

Abstract: A high-performance RAID system for a PC comprises a controller card which controls an array of ATA disk drives. The controller card includes an array of automated disk drive controllers, each of which controls one respective disk drive. The disk drive controllers are connected to a microcontroller by a control bus and are connected to an automated coprocessor by a packet-switched bus. The coprocessor accesses system memory and a local buffer. In operation, the disk drive controllers respond to controller commands from the microcontroller by accessing their respective disk drives, and by sending packets to the coprocessor over the packet-switched bus. The packets carry I/O data (in both directions, with the coprocessor filling-in packet payloads on I/O writes), and carry transfer commands and target addresses that are used by the coprocessor to access the buffer and system memory.

Abstract: A high-performance RAID system for a PC comprises a controller card which controls an array of ATA disk drives. The controller card includes an array of automated disk drive controllers, each of which controls one respective disk drive. The disk drive controllers are connected to a microcontroller by a control bus and are connected to an automated coprocessor by a packet-switched bus. The coprocessor accesses system memory and a local buffer. In operation, the disk drive controllers respond to controller commands from the microcontroller by accessing their respective disk drives, and by sending packets to the coprocessor over the packet-switched bus. The packets carry I/O data (in both directions, with the coprocessor filling-in packet payloads on I/O writes), and carry transfer commands and target addresses that are used by the coprocessor to access the buffer and system memory.

Abstract: A high-performance RAID system for a PC comprises a controller card which controls an array of ATA disk drives. The controller card includes an array of automated disk drive controllers, each of which controls one respective disk drive. The disk drive controllers are connected to a microcontroller by a control bus and are connected to an automated coprocessor by a packet-switched bus. The coprocessor accesses system memory and a local buffer. In operation, the disk drive controllers respond to controller commands from the microcontroller by accessing their respective disk drives, and by sending packets to the coprocessor over the packet-switched bus. The packets carry I/O data (in both directions, with the coprocessor filling-in packet payloads on I/O writes), and carry transfer commands and target addresses that are used by the coprocessor to access the buffer and system memory.

Abstract: A high-performance RAID system for a PC comprises a controller card which controls an array of ATA disk drives. The controller card includes an array of automated disk drive controllers, each of which controls one respective disk drive. The disk drive controllers are connected to a microcontroller by a control bus and are connected to an automated coprocessor by a packet-switched bus. The coprocessor accesses system memory and a local buffer. In operation, the disk drive controllers respond to controller commands from the microcontroller by accessing their respective disk drives, and by sending packets to the coprocessor over the packet-switched bus. The packets carry I/O data (in both directions, with the coprocessor filling-in packet payloads on I/O writes), and carry transfer commands and target addresses that are used by the coprocessor to access the buffer and system memory.

Abstract: 2-ALKOXYTETRAHYDROFURANS ARE CONVERTED TO 1,4-DIOLS UNDER HYDROLYSIS-HYDROGENATION CONDITIONS. The method may be coupled with the synthesis of 2-alkoxytetrahydrofurans to provide a highly efficient, two-step conversion of allylic alcohols to butanediols.

Abstract: A process for selectively ortho-alkylating a phenolic compound which comprises reacting the phenolic compound with an alkanol in the presence of a copper-zinc-aluminum mixed oxide catalyst.

Abstract: An improved process for producing tetrahydrofuran by dehydroacyloxylation or hydrolysis-dehydroacyloxylation of carboxylic acid mono- and diesters of 1,4-butanediol, the improvement comprising carrying out said process in the presence of a tungsten oxide catalyst.

Abstract: A process for selectively ortho-alkylating a phenolic compound which comprises reacting the phenolic compound with an aldehyde and hydrogen in the presence of a copper-chromium catalyst.

Abstract: A process for preparing tetrahydrofuran which comprises heating a carboxylic acid monoester of 1,4-butanediol in the vapor phase in the presence of a dehydroacyloxylation catalyst.

Abstract: A process for preparing tetrahydrofuran which comprises heating a carboxylic acid diester of 1,4-butanediol in the vapor phase in the presence of water and a hydrolysis-dehydroacyloxylation catalyst.