SU449355A1 - A device for displaying graphic information on a cathode ray tube screen - Google Patents

Description

(54) DEVICE FOR DISPLAYING GRAPHIC INFOS OF MATSIA ON THE SCREEN OF ELECTRON-BEAM PIPE

The device works as follows.

The code of the image coordinates on the screen of the CRT 10 in the form of syllables I the initial coordinate Y, the increments of the coordinates Y,

2

the second difference of the increments and the number

points and syllable X is stored in the memory block

12, which comes either from the communication unit

13, or from a light pencil 14 through shapers of codes in axes X 15 / and

A 16, a syllable shaper along the Y axis 17 and a comparison block along the X axis 18. From the memory block, the word enters the syllable register 1 along the Y axis and the syllable register 2 along the X axis.

The value of the Y coordinate from the area of the initial coordinate of the syllable register 1, and along the y axis through the adder of the Y coordinate, 6 is fed to the digital-to-analog conversion of the Y coordinate of the 8 1: and to the deflecting system 11 ZLT 10. Coordinate values of the Y formed by sequential addition in increment adders 3 and adder coordinate Y 6 differences of the first and second order stored respectively in areas 16 and 1 in register 1, the number of cycles of addition is determined by the contents of subtractive counter 4, in which when receiving a number from area 1, 2 numbers of reg points Stra zanosits Y value of the number of points reproduced without re referring to the memory unit. Simultaneously with decreasing the content of subtractive counter 4 by one and depending on the contents of the syllable register along the X 2 axis, the reversible counter of the X 7 coordinate is either added or subtracted or its content remains unchanged (with a vertical curve). In the X coordinate counter, the coordinate code is then generated, and the initial code value in counter 7 is set equal to the contents of subtractive counter 4 when the word is first transmitted. The values of the X and Y coordinates that are regenerated are supplied respectively.

to digital-to-analog converters at coordinates X 9 and U 8, and then to a deflection system.

Thus, a portion of the image of a curve on the screen of the PLC can be formed in one word when the memory block 12 is accessed once.

The control unit 5 is a combination of a pulse distributor and a two-input decimator and serves to synchronize the operation of the circuit.

Subject invention

A device for displaying graphical information on the screen of a cathode ray tube, containing digital-to-analog converters in X coordinates and connected to a deflection system, a light pencil connected to shaper codes on axes X and. Y connected respectively to a syllable former on the Y axis and a comparison unit on the X axis, connected to a communication unit and a memory unit associated with the syllable registers on the X and Y axes, a control unit connected to the syllable register on the X axis and through the reversing; {th counter of the X coordinate to the digital-to-analog converter on the X coordinate, characterized in that, in order to simplify the device and increase its speed, it contains increment adders that subtract the counter and adder of the Y coordinates; moreover, the input of the subtracting counter is connected to the syllable pei HcrpoM along the X axis, and the output of its other input is connected to the control unit; increment adders are connected to the syllable register along the y axis, the control unit and the addendum of the u coordinate associated with the syllable register along the y axis, the control unit and the digital-to-analog converter along the u coordinate.