Browse Prior Art Database

Architecture to Allow Use of Existing Software for Dissimilar Devices on a Multiple Device Attachment

IP.com Disclosure Number: IPCOM000050984D
Original Publication Date: 1982-Dec-01
Included in the Prior Art Database: 2005-Feb-10
Document File: 2 page(s) / 37K

Publishing Venue

IBM

Related People

Bhansali, MM: AUTHOR [+6]

Abstract

A method is described that allows the use of existing software, without major modification, for printer, Bisynch and Start/Stop on a multiport attachment card, such as that used with the IBM Series/1 processor.

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Architecture to Allow Use of Existing Software for Dissimilar Devices on a Multiple Device Attachment

A method is described that allows the use of existing software, without major modification, for printer, Bisynch and Start/Stop on a multiport attachment card, such as that used with the IBM Series/1 processor.

Multiple device controllers attached to Series/1 computers may report a controller busy condition code to Operate Input/Output (OIO) commands. Series/1 architecture requires that a controller-end interrupt be reported by the device controller if a condition code of controller busy was reported in response to an OIO command. The controller-end interrupt is presented with the base device address. This mechanism signals the I/O software to reissue the command that received the controller busy condition code. Multiple device controller attachments, until recently, have controlled multiples of the same type of device or communication lines. The current architecture for controller-end presents a problem of correlating controller busy and controller-end from a device, when the multiple devices on the attachment are dissimilar (e.g., printer, Bisynch and Start/Stop dissimilar multiple devices on multiport attachment as opposed to similar devices as in a disk attachment).

Based on the assumption that the existing software for dissimilar devices has to be used and the controller busy has to be reported, a method is set forth that allows the execution of a command fo...