Browse Prior Art Database

Initial Program Load With Status Signaling by Disk Arm Motion

IP.com Disclosure Number: IPCOM000083950D
Original Publication Date: 1975-Aug-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Fitzpatrick, JT: AUTHOR

Abstract

Most data processing systems have a permanent storage location that holds a very small program that permits the processor to make limited tests of other components of the system, and to fetch other programs that control further operations that are more complex and permit testing other components and loading further programs. This operation, called initial program load, proceeds step-by-step until the system is prepared for normal operation.

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Initial Program Load With Status Signaling by Disk Arm Motion

Most data processing systems have a permanent storage location that holds a very small program that permits the processor to make limited tests of other components of the system, and to fetch other programs that control further operations that are more complex and permit testing other components and loading further programs. This operation, called initial program load, proceeds step-by-step until the system is prepared for normal operation.

During early stages of initial program load, the system can notify the operating personnel of errors by simple means such as indicator lights on the processor console, and during later stages the system can use a printer or other output device for a more complex error message.

Some processors test an associated disk storage device before acquiring any capability of conventional communication with operating personnel. In a test of the disk, the processor issues a seek command and a read command for a particular track of the disk and it tests for predetermined data in the header of the track. This operation proceeds until an error is found, or until this part of initial program load has been completed.

In this system, the sequence of seek and read operations proceeds from one track to a remote track. For example, the processor can test the first track first, the last track next, then the second track, and so on. The motion or the read arm of the disk is audibly and vi...