Patent GB-1261372-A (GB)
Title: Improvements in or relating to data display arrangements
Inventor: GASKELL THOMAS ERNEST
IPC: G09G3/04
Filed: 1968-06-10
Abstract: 1,261,372. Digital data displays; display devices. MARCONI CO. Ltd. 2 June, 1969 [10 June, 1968], No. 27401/68. Headings G4H and G5C. A data display comprises a cylinder having a number of circumferential columns of characters, means for rotating the cylinder, means for illuminating selected characters and control means including a strip of magnetic material on the cylinder, or on a separate cylinder rotating with it, bearing stored representations of the characters and means for storing and reading out message signals indicating which characters are to be illuminated so that characters are repetitively illuminated in adjacent columns along a line so as to present a continuous display of the selected characters. The display cylinder 1, Fig. 1A, is hollow and transparent and is driven by motor 2. A further cylinder 3 on the motor shaft has two magnetic strips 6, for the character codes, and 7, for the incoming message signals. Each strip has a read/write head 4, 5. The cylinder 1 has eighty columns of characters, the same characters lying in lines parallel with the axis of the cylinder. Inside the cylinder are five rows of 80 lamps 10, Fig. 1B, spaced so that each coincides with a character. In line with each lamp is a light guide 11 attached to a display panel 12 of translucent material. Instead of using eighty separate lamps for each row an eighty-anode neon tube may be used. A single discharge tube having five lines of eighty anodes is also suggested. The lamps are lit once per revolution, to display the desired characters by comparison of data on the two magnetic strips. The strip store 6 comprises seven tracks in each character space of which is recorded a code representing that character. This is followed by a 3-bit coded member representing the first lamp row is represented by a separate bit. These are stored in 12 rows across the seven tracks. A number representing the next row of lamps follows with another twelve rows containing a bit for each lamp. This is repeated for the other lamp row. The whole of this data is repeated for the other character positions. Input may be from a keyboard 29, Fig. 3. The characters in 7-bit form are entered into coincidence register 31 and are counted by counter 32 which allots a column and row to each character. The register 31 receives the output of the counter and the output of the read amplifier reading the successive rows of data from strip 6. It controls the entry of the data into a column shift-register 33 and data is entered from this register via character coincidence gates 34 and write amplifiers 35 to appropriate ones of the 80 column positions and the three row number positions on strip 6. If data is entered via an input line 30 it is first written serially in track 24 of the strip 7 via buffer 38 and write amplifier 39. It is read from strip 7 via read amplifier 40 to the coincidence register 31. When all the information is stored in strip 6 it passes for display via read amplifier 41 to a row decoder and counter unit 42. Unit 42 enables appropriate gates 43 to light lamps and illuminate the characters to be displayed. Data from store 7 may be transmitted to other equipment via an output timing circuit 36 to an output terminal 44. The driving motor is controlled by unit 37 which compares the rate of input of data with the output rate and adjusts the motor to give the correct output rate.