SU465629A1 - Device for displaying graphic information on the screen of a cathode ray tube - Google Patents

Description

one

The invention relates to the field of automation and computer technology and can be used in electron beam display devices for data output from an electronic computer.

A device for displaying graphical information on a screen of a cathode ray tube, comprising a reversible counter, connected directly and through a generator to a digital computer, one digital-to-analog converter connected to a source of reference voltage, a cathode-ray tube and another digital-analog converter connected to a reversible counter .

The proposed device is characterized in that it additionally introduces p-2 digital-analog converters and an operational amplifier, with one input of additional digital-analog converters connected to a digital computer, and their outputs with an operational amplifier connected to a cathode ray tube, other inputs additional, starting SP - 1, digital-to-analogue converters of the terminal, respectively, with outputs

"-U

- digital-to-analog converters, and

output / 1st digital-to-analog converter - with reference voltage source.

This allows the functional capabilities of the device to be improved and to improve the accuracy of the presentation of graphic data.

Pa drawing shows the block diagram of the device.

The device contains a reversible counter 1 connected to a digital computer (DVM) 2, generator 3, basic 4, 5, and additional 6-10 digital-to-analog converters, reference voltage source 11, summed, operational amplifier 12, and cathode ray tube 13 .

The operation of the device will be considered on the example of the formation of a third-degree Nominom using five additional digital-analog converters.

From the digital computer 2 to the reversible counter 1 in the digital code, the initial coordinate A of the image is entered and the generator 3 is simultaneously started. Pa second inputs of digital-to-analog converters 7-10 supply the corresponding coefficients of the approximating polynomial image ai, a, Oz and a.

At the output of the digital-to-analog converter 4, the voltage is proportional to the indelible timeless X and is equal to t / on X, where op is the value of the voltage of the source 11 of the reference nanowire. Pa outputs of digital to analogue converters 5 and 6 appear

the voltages are t / on and Uo X, respectively, because the second inputs of the reversible counter 1 receive an independent variable X, and their first inputs are connected in series. The voltage U „p X passes the deflection system (not shown) the coordinates of the Aop of the cathode-ray tube 13 and to the first input of the digital-to-analog converter 7; since its second input from digital computer 2 supplies the digital code of the coefficient fl, then the voltage Uon (i X.

There is a similar connection between digital-analogue converters 5 and 8, 6 and 9. At the output of converter 8, the voltage is equal to on 0-2 A and at the output of converter 9 - and on oh X. At the output of converter 10, the voltage is proportional to coefficient ao, since its first input receives a signal (7 oi directly from the source 11 of the reference voltage, and the second input from the digital computer - the digital code ao. voltage t / on o-X, f / op, t / on o ,: X and and on о are fed to the inputs of the summing op amp 12 from the outputs of the transducers 7-10. its operational amplifier is formed by an analog value y coordinate of graphic image

U U „„ (a, X + + + ao),

which controls the beam bias along the coordinate Y of the cathode ray tube 13.

Thus, in each step of changing the independent variable A, the device calculates the value of the Y coordinate and the set of displayed points connects not piecewise broken, but curves represented by a third degree polynomial.

Subject invention

Graphic display device

information on the screen of the cathode-ray tube, contains 1, its reversible counter, connected directly and through the generator to the digital calculator, one digital-analogue converter,

connected to a reference voltage source, a cathode ray tube and another digital-to-analog converter associated with a reversible counter, characterized in that, in order to improve the accuracy of the display of graphic data, an additional n-2 digital-to-analog converter and an operational amplifier were introduced, some inputs of additional digital-to-analog converters connected to

digital computer, and their outputs - with an operational amplifier connected to a cathode-ray tube, other inputs are additional, starting with p - 1, digital-to-analog converters connecting the specificifrony respectively from the output.

analog converters, output of the dth digital-to-analog converter 35 and a source of reference data.