Browse Prior Art Database

Patch Data Transaction Mechanism

IP.com Disclosure Number: IPCOM000034850D
Original Publication Date: 1989-Apr-01
Included in the Prior Art Database: 2005-Jan-27
Document File: 2 page(s) / 37K

Publishing Venue

IBM

Related People

Harada, H: AUTHOR [+3]

Abstract

This article describes a patch data transaction mechanism between a DCA (Device Cluster Adapter) terminal and a subsystem controller. "Patch" is one method for mending or modifying a program temporarily. For enabling the patch capability for DCA terminals, three new commands between the DCA terminal and subsystem controller are defined. Terminals attached to the subsystem controller are classified into two groups. They are DCA terminals and TCA (Terminal Control Area) terminals. (Image Omitted) DCA terminals are designed such that most of the protocol processing work is performed by the subsystem controller. On the other hand, TCA terminals are designed to process the most work for subsystem controllers in order to reduce the controller's workload.

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Patch Data Transaction Mechanism

This article describes a patch data transaction mechanism between a DCA (Device Cluster Adapter) terminal and a subsystem controller. "Patch" is one method for mending or modifying a program temporarily. For enabling the patch capability for DCA terminals, three new commands between the DCA terminal and subsystem controller are defined. Terminals attached to the subsystem controller are classified into two groups. They are DCA terminals and TCA (Terminal Control Area) terminals.

(Image Omitted)

DCA terminals are designed such that most of the protocol processing work is performed by the subsystem controller. On the other hand, TCA terminals are designed to process the most work for subsystem controllers in order to reduce the controller's workload. However, DCA terminals have improved in the function which is locally performed by them, causing extension of the program size in DCA terminals. Though TCA terminals are able to make use of subsystem controller diskettes for storing their programs, DCA terminals did not have this capability. In order to make DCA terminals have the function of using the subsystem controller diskette, the following mechanism is described. The subsystem controller has an area for DCA terminals on its diskette or hard disk. Patch data for DCA terminals is stored in that area. The data is identified by their file names and patch levels. After a DCA terminal is powered on, the subsystem controller will send a "Query" command to the DCA terminal in order to inquire about the file name and the patch level whi...