GB796525A - Improvements in or relating to memory matrices embodying magnetic cores - Google Patents

Abstract

796,525. Electric digital-data-storage apparatus. PHILIPS ELECTRICAL INDUSTRIES, Ltd. April 4, 1956 [April 7, 1955], No. 10327/56. Class 106 (1). [Also in Group XXXIX] In a memory matrix comprising static magnetic memory elements, each element comprises two cores of ferromagnetic material in which the remanent flux is close to the saturation flux, one core being inductively coupled with a row input conductor and the other core inductively coupled with a column input conductor, and the two cores being coupled together by a separate winding. As shown, row conductors a-c are coupled to cores 1p-9p and can receive a positive or negative current pulse from devices A-C; and column conductors d-f are coupled to cores 1q-9q and can receive only negative current pulses from D-F. Positive and negative pulses switch a core to a " 1 " or " 0 " condition respectively, and each pair of cores such as 1p, 1q are coupled by winding 10 so that if one core is switched to " 1 " the other is switched to " 0 " and vice versa. Each element or core pair is in condition (0, 0)-both cores at " 0 "-to represent " 0," and condition (1, 0)-core p at " 1 " core q at " 0 "-to represent " 1 ". Information may be entered in a row at a time by a sequence of pulsing operations. Suppose, e.g. it is desired to write 110 in the top row shown, the elements being all initially in the " 0 " condition (0, 0). First a positive pulse is applied to a to switch all the elements to the " 1 " condition (1, 0); then negative pulses are applied simultaneously to a and f to return element 3p, 3q to " 0," the other elements in the row being switched to condition (0, 1); and finally negative pulses are applied to all column conductors d-f (or to d, e only) which restore elements 1p, 1q and 2p 2q to the" 1 " condition. Information is similarly entered in the other rows. Information may be read out by applying negative pulses to the row conductors, when any element in the " 1 " condition will be switched to condition (0, 1) thus producing an output pulse in the associated read-out winding g 1 . . . g 9 ; the elements are restored by negative pulses in the column conductors, the information not being destroyed by read-out. Other ways of entering and reading information are discussed in the Specification. In another embodiment (Fig. 5, not shown), for each row, separate conductors for applying the positive and negative pulses, and a further conductor through the q-cores for restoring the elements to " 1 " are provided, and the column conductors form read-out windings.