International Business Machines Corporation

Frederick Charles Yentz

William V Cranston, Iii

Jose P Basco

Robert Allen Hood

Hunter T Foy

John E McCloskey

Kendall A Honeycutt

James J Tout, Jr

Robert Chih-Tsin Eng

Eric H Stelzer

Rex E McCrary

Mark G McDonald

John W Galella

Allen R Hood

A card cage for holding expansion cards and filler panels within a computer system includes a ledge and a pivoted bar which is clamped in place adjacent to the ledge. A number of flexible portions of the pivoted bar clamp end portions of the filler panels and of brackets forming parts of the expansion cards against the ledge, so that these end portions are held in place while being electrically grounded. The bar is preferably pivoted about an axis extending parallel to the surface of the ledge and parallel to a slotted panel forming part of the card cage.

Pivoted latching bar for retaining expansion cards

A computer includes a main enclosure for housing a plurality of computer components. A subenclosure or card cage for housing a planar circuit board, including a CPU means, and at least one accessory board may be removably secured within the main enclosure, wherein the subenclosure, planar circuit board, and accessory circuit board may be selectively removed from the main enclosure as a unit. A connection means is provided to releasably electrically connect at least the planar circuit board to one of the computer components housed within the main enclosure.

Computer with modular removable card cage

A computer includes a main enclosure for housing a plurality of computer components. A subenclosure or card cage for housing a planar circuit board, including a CPU, and at least one accessory board may be removably secured within the main enclosure, wherein the subenclosure, planar circuit board, and accessory circuit board may be selectively removed from the main enclosure as a unit. A connection device is provided to releasably electrically connect at least the planar circuit board to one of the computer components housed within the main enclosure.

Industrial computer

Disclosed method and apparatus allow for balanced usage of resources in dual bus computing systems wherein: (1) principal resources of the system--including a processor, a local bus, local bus controls, and a memory subsystem--are contained in a single system unit (e.g. a card); (2) devices are coupled to the system unit and to each other through a device communications bus that is also accessible to the processor of the system unit; (3) the system processor is required to have principal access to the local bus, as a 'System Bus Master', for time critical functions such as memory refresh; and (4) the devices include one or more devices that are required to have controlling access to the resources of the system unit, and for that purpose are required to have controlling access to the local bus as Alternate Bus Master entities. The disclosed arrangement allows an Alternate Bus Master operating in a burst mode, in which several cycles of data transfer may occur consecutively, to have continuous access to the local bus after a single signal handshaking exchange with the local bus controls; subject to over-riding conditions which ensure timely accomplishment of the time critical functions controlled by the processor/System Bus Master. The over-riding conditions are detected by special logic that acts, when necessary, to interrupt Alternate Bus Master access to the local bus without affecting the state of connection between the respective Alternate Bus Master and the communications bus.

Providing alternate bus master with multiple cycles of bursting access

Growing community of inventors

Boca Raton, FL, United States of America

Frederick Charles Yentz