Browse Prior Art Database

ROS Patch Mechanism

IP.com Disclosure Number: IPCOM000040188D
Original Publication Date: 1987-Oct-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Inomata, T: AUTHOR [+3]

Abstract

This article describes the patch mechanism in the microcode stored in ROS (read only storage) of the machine to fix a microcode problem in the subsystem which has the down-load capability from the diskette of the controller/file-server to the machine. The new ROS Patch Mechanism requires the following resources. - File structure which enables down-load. - Transfer Vector Table which lists all entry addresses of microcode modules. Branch, call are done via this table. - RAM (random access memory) space where the defective microcode module can be copied. (Image Omitted) - Diskette drive to read the patch information (file) in the controller/file-server with the down-load capability. As shown in Fig.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 66% of the total text.

Page 1 of 2

ROS Patch Mechanism

This article describes the patch mechanism in the microcode stored in ROS (read only storage) of the machine to fix a microcode problem in the subsystem which has the down-load capability from the diskette of the controller/file-server to the machine. The new ROS Patch Mechanism requires the following resources. - File structure which enables down-load. - Transfer Vector Table which lists all entry addresses of microcode modules. Branch, call are done via this table. - RAM (random access memory) space where the defective microcode module can be copied.

(Image Omitted)

- Diskette drive to read the patch information (file) in the

controller/file-server with the down-load capability. As shown in Fig. 1, the field incident is reported to the microcode maintenance department, the cause is analyzed, and then the fix resolution is tested. After the effect of the resolution is verified, then the updated diskette which contains the following information is distributed to the customer site. - Defective microcode module information (Module ID, Fetch Ad dress, Target Address, Length) which should be copied from

ROS space into the RAM space. - New vector value to change the address for branch, call to the copied microcode module. - New address value to change the address for branch, call and data

for reference in the copied microcode module. - Corrective microcode logic or data to fix the problem. - Additional microcode logic or data to fix the problem. Re...