Browse Prior Art Database

Controller Interconnections

IP.com Disclosure Number: IPCOM000052419D
Original Publication Date: 1981-Jun-01
Included in the Prior Art Database: 2005-Feb-11
Document File: 2 page(s) / 39K

Publishing Venue

IBM

Related People

Bailey, JA: AUTHOR [+3]

Abstract

A controlling unit is connected to a controlled unit via three sets of lines. A first set of lines, A, carry data signals; a second set of lines B carry control signals; a third set of lines, AB, are switched between carrying data signals and control signals, depending upon the phase of operation. During a selection or control phase of operation, lines AB can carry control signals, such as tag signals. During a data processing phase of operation, lines AB carry data signals. This arrangement provides for greater data bandwidth and control bandwidth, with a minimal number of lines.

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Controller Interconnections

A controlling unit is connected to a controlled unit via three sets of lines. A first set of lines, A, carry data signals; a second set of lines B carry control signals; a third set of lines, AB, are switched between carrying data signals and control signals, depending upon the phase of operation. During a selection or control phase of operation, lines AB can carry control signals, such as tag signals. During a data processing phase of operation, lines AB carry data signals. This arrangement provides for greater data bandwidth and control bandwidth, with a minimal number of lines.

A controlling unit has a controlled unit SELECT circuit and a data processing circuit "PROCESS". The SELECT circuit controls the PROCESS circuit, as is well known in the data processing art. The controlled unit also has a SELECT circuit (SEL) which responds to the controlling unit SELECT circuit. The controlled unit further has a PROCESS circuit, which is designed to cooperate with the PROCESS circuit of the controlling unit. The controlling unit may be a control unit, while the controlled unit may be a peripheral magnetic storage device. Prior interconnections provided for data transfer lines A and tag lines B, which were exclusively used for those functions. Limited extension of data lines A, as well as control lines B, can be achieved by time shifting lines AB. During a control phase, such as during selection and deselection, the controlled unit lines AB c...