Barbara Gayle Bailey

US Patent:

60921234, Jul 18, 2000

Filed:

Jul 17, 1997

Appl. No.:

8/895716

Inventors:

Jeffrey Raymond Steffan - San Jose CA
Barbara Yvonne Bailey - San Jose CA
Calvin Kuo-Lee Tang - Saratoga CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1314
G06F 1320

US Classification:

710 8

Abstract:

The present invention concerns a method, apparatus, and article of manufacture which provides an efficient way to change the function of a programmable logic unit included in a control device--where the control device manages the operational characteristics of a hardware unit--without having to disable system access to the hardware unit during the updating process. The hardware unit remains fully functional throughout execution of the updating method. To perform the update, the hardware unit must be connected to a host system by at least two communication channels. Each communication channel includes a control device including a programmable logic unit. The programmable logic unit is pre-programmed by a first data set which establishes its predetermined operational characteristics. Upgrading the programmable logic unit is accomplished by logically removing one of the communication channels leading from the host system to the hardware unit. A second data set is copied to the programmable logic unit along the removed channel after its integrity is verified.