System for transferring data between I/O devices and main or expanded storage under dynamic control of independent indirect address words (IDAWs)

US5461721A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Roger L. Cormier · Pleasant Valley, US
• Robert J. Dugan · Hyde Park, US
• Kenneth J. Fredericks · Poughkeepsie, US
• Peter H. Gum · Poughkeepsie, US
• Moon J. Kim · Wappingers Falls, US
• Allen H. Preston · Poughkeepsie, US
• Richard J. Schmalz · Beacon, US
• Charles F. Webb · Wappingers Falls, US
• Leslie W. Wyman · Poughkeepsie, US

Key dates

• Filing date: Apr 14, 1993
• Grant date: Oct 24, 1995
• Expiry date: Apr 14, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F12/10
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

Enables an I/O channel program to use IDAWs (indirect data address words) to control data transfers from/to an I/O (input/output) device to/from either or both of ES (expanded storage) and/or system MS (main storage), in which data moved to/from ES does not move through MS. ES and MS are plural electronic storage media in a data processing system, and the I/O device is any I/O device selectable by the system. Intermixing of data transfers between ES and MS may be controlled by a single IDAW list accessed by a channel control word (CCW) in a channel program in a data transfer direction indicated in the CCW without any channel mode change.