Browse Prior Art Database

Memory Selection System

IP.com Disclosure Number: IPCOM000097456D
Original Publication Date: 1962-Dec-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 28K

Publishing Venue

IBM

Related People

Gersbach, J: AUTHOR

Abstract

A single unipolar pulse driver read selects and also write selects a row of cores when the row drive winding is equipped with a delay element.

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Memory Selection System

A single unipolar pulse driver read selects and also write selects a row of cores when the row drive winding is equipped with a delay element.

The row drive winding passes from the driver through the row of cores to a delay element and folds back through the row of cores. The negative drive pulse thus traverses the row of cores in the read aspect and then in the write aspect. A delay element placed at the fold in the drive line provides sufficient delay so that the read aspect and the write aspect of the drive pulse are distinguishable in time.

To read and then write (regenerate) the row of cores, the pulse driver is pulsed once only. The read aspect of the drive pulse is oriented to read the core. The drive pulse, after the delay, is in its write aspect. It again passes through the row of cores in the write direction. A bit pulse coinciding with the write aspect of the drive pulse writes or regenerates the core.

A drive pulse duration greater than the period of the delay element results in a read blank write sequence. The duration of effective read and write fields is equal to the period of the delay. Although write current starts to flow immediately after the period of the delay, its field is cancelled by the opposing field of the remaining portion of the drive pulse, which is still traversing the row of cores in the read aspect. This field cancelling produces the blank between read and write. After the drive pulse ends, the delay elemen...