Patent GB-762094-A (GB)
Title: Improvements in or relating to electrical storage of coded information
Inventor: WRIGHT ESMOND PHILIP GOODWIN
IPC: H04L12/54
Filed: 1953-06-10
Abstract: 762,094. Electric digital-data-storage apparatus. STANDARD TELEPHONES & CABLES, Ltd. June 4,1954 [June 10, 1953], No. 15938/53. Class 106 (1). [Also in Group XL (b)] An arrangement for the storage of information comprises a number of members for storing information to be received or transmitted, means for applying a distributer mark to a store as being the next to be used for reception or transmission and transferring the mark from store to store and means for detecting the mark and for controlling the direction of the information into or from the marked store. The signal elements are recorded on a drum section which has at the beginning of the section an element position T indicative of reception or transmission, and elements M1, M2 ... Mn providing distributer operation for reception and transmission. The drum is rotated at 50 revolutions per second and produces clock pulses - p, at 500 per second. A wave form PT is positive for the pulse T and wave form L is positive for the last element on the track. Pulses PM, WM are positive respectively for the duration of the M pulses and for the periods of the code combination of the elements of the individual characters. Three relatively delayed trains of short pulses t1, t2, t3 are produced, a pulse t1, t2, t3 occurring within the period of a PT or PM pulse. The timing of the operations is controlled by circuits C1, C2, the circuit C1 having a cycle corresponding to ten of the - p pulses, i.e. 20 ms.,. and the circuit C2 being stepped after each interval of 20 ms. The asterisks indicate the elements which are initially energized. Recording and storage of received characters. When the arrangement is to be used for receiving and storing information, the key KRO is in the left-hand position, and the initial spacing impulse operates the trigger F1 to position 1 so that gate G1 opens and permits gate G2 to pass pulses - p to step the counter C1. At time 30 ms. after the beginning of the start element denoted by c2.2, c1.5, the pulse from Tp is applied to gate G29 and if it is a space, element 5 of the register R1, of the type described in Specification 663,754, [Group XL (b)], is energized. At subsequent mid-element instants the remaining code elements are registered on elements 4 ... 1 of the register R1. At the end of 120 ms., C2 will step to c2.7 and the PT pulse occurring during the next revolution of the drum will operate F4 to f4.1 and the subsequent PM pulse operates F5 to position 1. The energization of f4.1 opens gate G37, Fig. 5, so that a pulse t2 opens gate G45 and operates recording device F9 to position 2 to record a " 0 " in the M1 position. At time t3 in the same PM pulse gate G19 opens and trigger F4 returns to the position 2. When the wave form WM corresponding to the first section appears gates G42, G43 are prepared, and at time t2 if r 1.51 is positive, G44 will open and operate F9 to position 1 and cause a space to be recorded. At time t3 gates G14, G15, Fig. 3, will open and, step the pattern to the right so that the second element is on R1.5 and r1.5.1 will be positive if a space. By means of the inverter XI, a mark will make r15.0 positive. For the PM pulse coinciding with M2, f3.1 is not energized and gates G34, G35 are closed. Gate G36 is opened by f4.2 and f5.1, and at time t2, G44 is opened, F9 is operated to position 1 and " 1 " is recorded in the M2 position. At time t3 during this PM pulse G21 and hence G22 will open, and with F5.2 re-operated the existing elements on the drum will be again recorded. Gate G35 causes M3 to be recorded as " 0 " and the third character re-recorded. When the second character is sent from T/p and the time scale reaches the position C2.7, circuit F41 is operated by/1.1 1 and PT and f4.1 is energized so that the PM pulse occurring with M2 opens F51 the contents of R1 are recorded by F9 in position 2 and since f4.2 is not energized until time t3 of the PM pulse coinciding with M2, both M1 and M2 will be recorded as " 0 " by gate G37. Until time t3 of the PM pulse coinciding with M3, f5.1 remains energized so that a " 1 " is recorded for element M3 by means of G36. The third character is passed from the teleprinter to the register R and the first " 1 " coinciding with a PM pulse will be M3 causing f4.1 to be energized and M3 to be recorded as " 0 ". The PM pulse opens G20, Fig. 4, energizing f5.1 and the contents of R1 corresponding to the third signal from the teleprinter are recorded on the drum. As there are no further Mn elements of condition " 1 ", a pulse PT coinciding with element T is used to reset F5 to the condition with F5.2 energized. Retransmission of stored characters. For this operation the key KRO, Fig. 2, is moved to the right and an impulse X occurring with a PT pulse opens gate G32 and at time t2 operates device F9 to record a " 1 " in the position T on the drum. During the next cycle when the element T is read F3.1 will be operated and F6.1 will be operated by the opening of gate G23. For the next PM pulse, i.e. coincident with M1, G38 is operated and F9.1 operated to cause M1 to be recorded as " 1 ". Also at time t2 of PM, G28, Fig. 4, is opened and F7 operated to position 1 whilst at time t3 of the pulse PM, G24 is opened and F6.2 re-energized. On the occurrence of the WM wave form at time t2 if the first element is a space, F3.1 is operated, and via gate G16, Fig. 3, element R1.0 is energized, and at time t3 the state of R 1.0 is passed to R 1.1. By subsequent pulses t2, t3 occurring during the WM positive wave form the elements are passed to R1.0 and the pattern stepped. When the PM pulse coinciding with M2 appears gate G29 is opened at t1 and F7.2 is re-energized. At the same time G5, G6 are operated and F2 is moved to position 1 so that the time scale C1, C2 is brought into operation. At time cl.2, G46 in Fig. 6 opens and F10 moves to position 1 to operate relay TR to space. At successive times c2.2, c2.3 ... c2.6, G50 and G52 will open and G51 or G53 will be opened in dependence on the first element passing from R1.5. At cl.7 G55, G15 will open and R1 will be stepped so that the element R1.5 is mark for the signal being retransmitted and r1.50 is positive. At c2.3 G.53 opens and at cl.2, F10 changes over to F10.2 and TR is operated to send mark. At c1.7 the register is advanced and as the third element is a space TR returns to space at c1.2 of the next cycle. When c2.7 is reached, at time c1.2, F10.2 is energized to transmit mark for the stop signal which persists until a time set up by cl.7, c2.8, i.e. 150 ms., from the commencement of the start signal when gate G7, Fig. 2, operates F2 to position 2 producing a reset. pulse T to open gate G4 and restore the time scale to positions c1.1, c2.1. When F2.2 is re-energized, the first PT pulse which follows opens G23 and F6.1 is energized and the PM impulse of M2 opens gate G28 for F7.1 and the elements of the second character are passed to R1.0 and stepped to the positions R1.5 to R1.1. Circuit F7.2 is re-energized for the PM pulse coinciding with M3. At .the same time F2.1 is operated and the time scale started so that the contents of R1 are transmitted to the line. The third character is transferred to the register and transmitted in a similar manner, and since M1, M2, M3 aie all " 1 ", G28 cannot open. Circuit F6 is returned to position 2 by the last pulse PL and element T is recorded as " 1 " via gate G32. After the characters have been transmitted, KRO is restored to the lefthand position, G33 (Fig. 5) is opened and F9.2 is energized causing a " 0 " to be recorded for T. Also the next PT pulse opens G23, Fig. 4, causing F6.1 to be energized and G31 opens so that F8.1 is energized. At time t3 in the subsequent PM pulse, G26 is opened and F6.2 operated. As F6.1 is still energized at time t2 of this PM pulse, a " 1 " is recorded for M1, but M2, M3 will be recorded as " 0 ". The pulse PL at the end of the section restores F8 to the position 2. Modifications. More than one message or set of data may be stored by a multiplexing arrangement similar to that shown in Specification 744,356, and messages or sets of varying length recorded with the use of an end-of-message character. The drum may have a number of tracks with the recording and reading heads staggered around the periphery. Further the transfer from the register to the store may be effected element-by-element instead of character-by-character with a bi-stable device in lieu of the pattern register. Specifications 713,902, [Group XL (c)], 744,352, 744,357 and 744,358 also are referred to.