Patent GB-1479584-A (GB)
Title: Data terminals and data processing apparatus incorporating such terminals
IPC: G06K17/00
Filed: 1973-07-14
Abstract: 1479584 Data terminal SOLARTBON ELEC TRONIC GROUP Ltd 15 July 1974 [14 July 1973 13 March 1974] 33643/73 and 11137/74 Heading G4H A data terminal comprises a keyboard 62, a display 2 having a plurality of zones 64a-70a corresponding to respective keys 64-70 of the keyboard and being arranged to display in each zone an indication of the message or part of a message represented by the key corresponding to that zone, means responsive to manual selection of a key to change the visual appearance of the display so as to indicate which key has been selected, and means 76 operable when a key has been selected to communicate the message or part of a message represented by the selected key to a data processor 82. As shown in Fig. 2, the keyboard incorporates capacity touch switches 64-70 selected in turn by a scanner 100 which is addressed by the outputs 103-104 of a counter 152 incremented by clock pulses from a circuit 110-140. When the scanner reaches a touched key, its output 102 causes flip-flop 142 to change state at the next clock pulse, the resulting signal 150 serving to stop the counter, whose outputs 103-104 (together with the flip-flop output 148) constitute a key-identifying signal 74. Display 2 may be a CRT which is scanned by counters 24, 26 incremented by a clock 10. Data to be displayed is fed from a computer store 82a in the processor to a random access memory 32, thence in 6-bit ASC11 code to a read only memory 46 which produces video signals in 5 Î 7 matrix form for supply via a register 20 to the display. Data in the zone corresponding to the selected key may be displayed light on a dark background while the other zones are displayed as dark on a light background, or vice-versa; a bit 42 from RAM 32 indicates which type of display is required at each moment for the signal 40 being transmitted to ROM 46, the bit and the register output 54 being fed to an XOR gate 56. When an operator has pressed a key, he can see by looking at the display whether it was the required one. If so, means 76 is then actuated; this may be a switch located beneath the keyboard and actuated by subsequent pressure on the touched switch. The processor computer 82 may be used primarily as a data store, in which case the function of the keys is to select progressively more detailed information from the store for display; alternatively or additionally the computer may be used for computation or control, when the keys are used to modify the execution of a program, e.g. by changing values of parameters used therein, an operation being initiated by switch 76 when the display has been verified. For example, the computer may contain detailed information concerning a number of simulated aircraft under radar surveillance, the computer forming part of a simulator for training air traffic controllers, each aircraft being controlled by a "pilot" (the trainer). The initial display may be the flight numbers of, e.g. four aircraft: an aircraft is selected by touching a key, when this number (in contrast to the others) is displayed dark against a light background. When the "pilot" has verified visually that he has selected the correct flight number, he operates switch 76. The computer program is then operated to retrieve from the store further information relating to the chosen flight number: the display will then show, e.g. speed, heading, height and destination for the chosen flight number. Any of these (e.g. speed) may then be changed by touching the respective key so that the display is changed again to indicate (e.g.) four speeds, one of which may then be selected.