GB754393A - Data storage devices of the magnetic core type - Google Patents

Abstract

754,393. Circuits employing bi-stable magnetic elements. MAX-PLANCK-GES. ZUR FORDERUNG DER WISSENSCHAFTEN E.V. July 29, 1954 [Aug. 3, 1953], No. 22209/54. Class 40 (4). [Also in Group XIX] Selecting apparatus for a magnetic-core matrix store comprises selection transformers, also arranged as a matrix, each having at least four windings, first and second windings being connected respectively in series by rows and columns to selection-pulse leads, third windings being passed by a sustained direct-current sufficient to restore a reversed transformer at the end of the selection pulses, and fourth windings individually supplying output signals to select corresponding rows of the storage matrix. For a two-dimensional matrix store comprising sixteen rows of cores 7, Fig. 3, sixteen selection transformers are arranged in a square matrix and have their row and column windings connected to corresponding row switch tubes 8 and column switch tubes 9. The output windings 5 are connected to respective rows of windings on the store cores 7. Windings 4 are passed by a direct-current which normally maintains each selection transformer in a state P, Fig. 2. When one each of the tubes 8, 9 produces a pulse, a corresponding transformer is reversed and produces in its winding 5 a pulse which will restore any reversed cores in the selected row of the store matrix to produce pulses in their column windings. As the pulses produced by the tubes 8, 9 cease, the reversed transformer is restored by the direct-current winding and produces a pulse in the corresponding row of windings in the store. If the column windings of any of the cores are also pulsed at this time, the state of those cores will be reversed. The transformers may be so arranged that the writing-in pulses are appropriately smaller than the readout pulses, unless the storage cores also have biasing direct-current windings. The pulses produced by the tubes 8, 9 are maintained constant by limiting diodes 10 connected to their control grids and by the negative-feedback action of cathode resistances. For a threedimensional matrix store, Fig. 5, two matrices 26, 31 of selection transformers are used to select a row and a column in each digit-place plane. The output winding of each transformer is connected in series with all of the core windings of the corresponding row or column in all of the digit-place planes. A third read-out and writing-in winding on each core is connected in series with corresponding windings in the same digit-place plane. Regenerating arrangements (see Group XIX) also are described.