Patent GB-950436-A (GB)
Title: Record card controlled apparatus
IPC: G06F7/02
Filed: 1962-09-11
Abstract: 950,436. Statistical apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. Sept. 11, 1962 [Sept. 11, 1961; Nov. 13,1961], No. 34719/62. Heading G4M. General. In record-card controlled apparatus primary and secondary sets of cards are fed from hoppers 10, 11 and are read by brush sensers 22, 23, Fig. 2a, data sensed by the brushes being stored in sections of a magnetic core matrix 66, Fig. 2b designated primary sequence and secondary sequence respectively. During the next machine cycle the contents of the primary sequence and secondary sequence sections are read out serially by bit into single bit registers 87, 90 and are then transferred to the sections of store 66 designated primary and secondary. During a later part of this cycle, data read from the next primary and secondary cards is entered into the primary sequence and secondary sequence sections During a reading operation, the contents of the primary and secondary sections are also read out into single bit registers 88, 89, and a comparison may thereby be effected between the data on two successive cards in each stream and also between the data on the leading primary and secondary cards. Card deflectors 47, 51 and 56, 59 are continuously operated to direct both primary and secondary cards to merging pocket 46, the order in which the cards arrive at pocket 6 being determined by selective operation of clutches 301, 303 and 305 which are controlled in accordance with the results of the comparisons above mentioned. Data coding, checking and mode operation. Three modes of operation are provided, alphanumeric, numeric with blanks equal to zero, and numeric with blanks detected as errors, the machine being programmed by a plugboard 65 to select any of these modes for the different columns in a field of 28 columns selected by the plugboard. As the cards pass through the sensing stations a magnetic timing device connected to the card drive conditions different combinations of cores in store 66 in sequence so that the appropriate combinations of cores are set by the sensed perforations (bits 12, 11, O and A to E) Fig. 12. During a transfer operation between the different sections of store 66 via registers 87, 90, generator 185 or 186 produces additional bits G1, G2, Fig. 12 for the special characters blank, 12,11, 0-1, these being entered in the primary or secondary section. All characters read out from store 66 into registers 87-90 are checked to see if they are valid for the mode then in operation, the machine being stopped if an invalid character is detected. In order to select the different modes, plugboard 65 has a section containing 28 hubs which, when taken in order, correspond to the sequence of 28 characters read out from each section of store 66. Those hubs which correspond to the columns which are the first in groups of consecutively-read columns for which the different modes apply, are wired to set the appropriate one of three bistable circuits (only one of which can be set at a time) controlling the checking circuitry according to the desired modes. Comparison circuitry 161. Each of the 28 characters read out from the primary sequence section of store 66 is compared bit-by-bit with the corresponding character from the primary section. Comparisons are also made between the characters from the secondary sequence and secondary sections and between the characters from the primary and secondary sections. In each of the comparison circuits one of three bistable circuits is set to indicate high, low, or equal, and a comparison operation is stopped as soon as a high or low decision is arrived at, although the read-out continues for all 28 characters, so that a comparison of all bit positions in the field is only effected if the fields are identical. Merging operation. The primary and secondary cards are previously arranged in sequence in hoppers 10, 11. The outputs from the three comparison circuits, each of which indicates high, low or equal, are applied to gating circuits which select one or more of clutches 301, 303, 305 for operation in such a way that the primary and secondary cards arrive at pocket 46 in the correct merged sequence.