Patent GB-989947-A (GB)
Title: Improvements in memory systems
IPC: G11C11/44
Filed: 1961-05-17
Abstract: 989, 947. Electric data-storage apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. May 17, 1961 [May 18, 1960], No. 5916/61. Heading G4C. In a binary data storage system which includes a plurality of registers each having a plurality of binary storage stages with each stage connected to corresponding stages in the other registers and to corresponding sections of an input device, each register may have all its stages conditioned simultaneously for read-in of data from the input device or for read-out, and data can be entered into a plurality of registers and the read-out device simultaneously. Fig. 1 shows two ordered of a cryogenic store comprising three registers, and input device 17, and output terminals 101. . . 104. Terminals 21, 22 are adapted to receive supplies of current for lines 31 to 34, and the READ, WRITE, and RESET terminals 151. . . 156, 176 receive current pulses at appropriate times. Data entry is performed by setting switch arms 51, 52 &c. could or "0" contacts, as appropriate. With switch arm 51 on contact 55 current flows to earth via cryotron gate 76, rendering the latter resistive and so directing current from terminal 21 into line 32. If WRITE line 153 of register 3 is now energized momentarily, driving cryotron gate 205 resistive, the current in line 32 is directed around loop 141a, 141b 141c and 141d. If now the current to terminal 21 were terminated, persistent current would be established in the cryotron storage loop 141 to represent binary "1"; conversely, the absence of persistent current would represent binary "0". The data set up on the entry switches 51, 52 &c. could be entered in all three registers simultaneously by energizing all three WRITE lines 151. . . 153 instead of just one. Also, by supplying current to terminals 91, 92. . . &c. the current-carrying lines of the series 31, 32, 33, 34. . . &c. will actuate cryotron gates of the series 111, 112, 113, 114. . . &c. to defect the current to those terminals 101, 102, 103, 104. . . &c. representing the registered data. To read previously stored data to the output or to another register or registers, current is restored to terminals 21, 22 &c. and the reset line 176 is energized momentarily to make cryotron gates 177, 178 &c. resistive and so cause current from terminals 21, 22 to flow only in lines 31, 33. The READ line 154, 155 or 156 of the register storing the required data is now energized. If READ line 156, for example, cryotron gates 211, 212, &c. are made resistive and tend to deflect current in lines 31, 33 round sense loops 145, 146. However, if storage loop 141, for example, is carrying persistent current (representing binary "1") it renders cryotron gate 201 resistive thus blocking effective current in line 31 and deflecting the current to line 32, the effect being that current from terminal 21 flows via 141a, 141b, 141c and 141d towards terminal 41. Transfer of the data into any other register or to the output, can now be effected by energizing the respective WRITE line &c. as described above. Other embodiments providing for greater flexibility are also described. Specification 862,178 is referred to.