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Error Activated State Memory for Disc File

IP.com Disclosure Number: IPCOM000075902D
Original Publication Date: 1971-Dec-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Miller, TH: AUTHOR

Abstract

The state memory records the time when any error occurs in an attachment for a disc file, for example, allowing the program controlling the attached CPU to reconstruct the state of the attachment between the CPU and disc file during the time of the error, whereby the fault may be isolated by analyzing the collected statistics.

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Error Activated State Memory for Disc File

The state memory records the time when any error occurs in an attachment for a disc file, for example, allowing the program controlling the attached CPU to reconstruct the state of the attachment between the CPU and disc file during the time of the error, whereby the fault may be isolated by analyzing the collected statistics.

The state memory basically consists of four polarity-hold circuits 2, 3, 4 and
5. Basically, a polarity-hold circuit provides an up output when a strobe input goes up, assuming that a data input has previously gone up; and the output remains up, even though the strobe output goes down until the data output goes down at the same time as the strobe output is up. Each polarity-hold circuit 2, 3, 4 and 5, acts as a gate to allow the states or times of the disc attachment (count time, key time, data time and check time) to proceed directly through the polarity- hold circuit and into a sense bit to the CPU, sense count time 12, sense key time 13, sense data time 14 and sense check time 15. On an occurrence of an error in the disc file or the attachment between the disc file and the CPU, these states 12, 13, 14 and 15 are latched or remembered by the polarity-hold circuits 2, 3, 4 and 5.

The strobe pulse is applied to the polarity-hold circuits 2, 3, 4 and 5 and constitutes the output of a flip latch 1 supplied over line 16 which indicates an error in the disc file or in the attachment of the disc file to the CPU when latch 1 ...