Browse Prior Art Database

Combined Read Only Read Write Memory

IP.com Disclosure Number: IPCOM000093026D
Original Publication Date: 1967-Apr-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Dickinson, WE: AUTHOR

Abstract

In the operation of core memory planes over extended periods of time, certain read-only cores are initially set to either remanent state of magnetization and never switch to the other, although the same read-write circuitry is used for both the read-only and read-write sections. However, currents in the windings intended to switch other cores disturb the read-only cores so that eventually they can reside in the incorrect remanent state. In order to assure that the read-only core positions provide a permanent univalue rcadout, jigs are constructed which, when pressed against a core plane with cores in all positions, destroy read-only cores by crushing with projections appropriately positioned.

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Combined Read Only Read Write Memory

In the operation of core memory planes over extended periods of time, certain read-only cores are initially set to either remanent state of magnetization and never switch to the other, although the same read-write circuitry is used for both the read-only and read-write sections. However, currents in the windings intended to switch other cores disturb the read-only cores so that eventually they can reside in the incorrect remanent state. In order to assure that the read-only core positions provide a permanent univalue rcadout, jigs are constructed which, when pressed against a core plane with cores in all positions, destroy read-only cores by crushing with projections appropriately positioned. Additionally, to insure that the permanent 1's in the read-only section are actually read as 1's, the normal read-write cycle is reversed when reading such section, i. e., a write- read destroy read-only cores by crushing with projections appropriately positioned. Additionally, to insure that the permanent 1's in the read-only section are actually read as 1's, the normal read-write cycle is reversed when reading such section, i. e., a write-read cycle is used.

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