Browse Prior Art Database

Increased Hardware Error Isolation During Disk CSIPL

IP.com Disclosure Number: IPCOM000042233D
Original Publication Date: 1984-May-01
Included in the Prior Art Database: 2005-Feb-03
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Lundak, JC: AUTHOR [+2]

Abstract

The problem of isolating a hardware error during disk CSIPL (Control Store Initial Program Load) is minimized by the error-isolating software within the disk CSIPL loader. The disk CSIPL loader is used to load diagnostics, the Diagnostic Control Program (DCP), and the System Support Program (SSP) into memory within a computer system. It is during the execution of the disk CSIPL loader that hardware error isolation is performed. In one prior computer system, continuous retries were made when hardware errors occurred but no error isolation was performed. In another system, an error code was displayed to indicate the load in which the hardware error occurred. No attempt to isolate where the error was occurring was implemented.

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Increased Hardware Error Isolation During Disk CSIPL

The problem of isolating a hardware error during disk CSIPL (Control Store Initial Program Load) is minimized by the error-isolating software within the disk CSIPL loader. The disk CSIPL loader is used to load diagnostics, the Diagnostic Control Program (DCP), and the System Support Program (SSP) into memory within a computer system. It is during the execution of the disk CSIPL loader that hardware error isolation is performed. In one prior computer system, continuous retries were made when hardware errors occurred but no error isolation was performed. In another system, an error code was displayed to indicate the load in which the hardware error occurred. No attempt to isolate where the error was occurring was implemented. In the present arrangement, when an error occurs during disk CSIPL loader execution, the operation is retried 16 times to try to recover. When the 16 retries are exhausted, error isolation then takes place. If the error is isolated to a device in the file subsystem, the error code passed to the disk CSIPL loader is modified with a number to reflect this fact. The error code is then displayed, and machine execution is halted. Error codes consist of four hexadecimal digits which are displayed in LEDs (light emitting diodes) on the system control panel. The two leftmost hexadecimal digits identify which IPL (Initial Program Load) load the error occurred. The two rightmost hexadecimal digits ide...