Zitel Corporation

Rasilient, Inc.

Mohammad F Rydhan

Robert L Papenberg

David H Wotring

Paul Voloshin

Runchan D Yang

Mohamed M Talaat

Yee-Hsiang Sean Chang

John S Hoch

An adapter unit operative to support access of an SATA storage device by a plurality of hosts associated with separate host adapters. The adapter unit includes a multiplexer coupled to an arbiter. The multiplexer receives a plurality of sets of communication signals, one signal set for each host adapter. The multiplexer then selects one of the signal sets based on a control signal and couples the selected signal set to its output. The arbiter receives requests from the hosts to access the SATA storage device, selects a particular requesting host, and provides the control signal indicative of the specific host granted access. The host adapter for the granted host and the SATA storage device are placed in a PHY READY power management state, prior to a read or write access, and are placed in a PARTIAL power management state after the read or write access.

Method and apparatus for arbitrating access of a serial ATA storage device by multiple hosts with separate host adapters

A fault tolerant clock system is provided by utilizing redundant clocks which are maintained in synchronization, with voting circuit serving to select one of a plurality of matching clock signals for use. A resistor is coupled in series between the crystal and the oscillation circuit in order to establish a desired duty cycle of the clock signal. A series connected diode capacitor network is connected between a node of the oscillator circuit and a power supply in order to ensure initiation of oscillation.

Fault tolerant memory system

A memory system in which fault tolerance is achieved utilizing redundant clocks. The redundant clocks are synchronized, and a voter is used to deselect nonmatching clocks, thereby avoiding clocking errors. A circuit is provided to ensure a nonoscillating clock provides an output level at a desired state. Another circuit is provided to ensure oscillation upon power up.

Growing community of inventors

San Jose, CA, United States of America

Mohammad F Rydhan