GB841368A - Improvements in electric digital computers - Google Patents

Abstract

841,368. Digital electric calculating-apparatus. SOC. D'ELECTRONIQUE ET D'AUTOMATISME. July 5, 1957 [July 5, 1956; July 26, 1956], No. 21444/57. Class 106 (1). In an electric digital data computor of the general-purpose stored-programme type at least one section of the fast access store includes means for comparing simultaneously a reference word with parts of the contents of all the word locations in that section and means, controlled by the comparing means, for writing in and reading out information to and from the remaining parts of selected word locations. In the magnetic core matrix store shown, a row (storing a word) may be selected by activating a corresponding gate 11, information being entered or read out by sequential activation of column gates 12. Alternatively, a word may be selected by comparison of the " tag " part stored in columns y 1 to y j-1 with an " address " supplied on leads 10 from a static register 8. Upon comparison agreement in any row, a gating arrangement 4, 5 supplies a signal to line 7 to open gates 14 and 16 for parallel input and output respectively to and from the cores in columns y j to y p . Several sets of selecting arrangements 4, 5, 14, 16 and corresponding registers 8 may be provided associated with different groups of cores. Which of the address selection means is effective is determined by a special digit in the computer instruction word. The computer (Fig. 2, not shown) comprises a first store with two-way selection as shown, a second store with only the usual row-column selection, a multi-accumulator arithmetic unit, and a control unit including a sequence control member. Each computer instruction includes a three-valued symbol " C " which determines whether a break in the normal programme sequence occurs. Reference is made to modification of instructions and to the use of subroutines. The invention may be applied to a store comprising one-word recirculating loops. Specification 676,393 is referred to.