SU1188778A1 - Device for displaying circles and ellipses on screen of cathode-ray tube (crt) - Google Patents

Abstract

A DEVICE FOR DISPLAYING ENVIRONMENTS and ellipses ON THE SCREEN ELECTRON-BEAM TUBE (CRT), containing the first and second digital-to-analog center coordinate converters, whose inputs are the first and second inputs of the device, and the outputs through the beam deflection amplifiers are connected to deviating systems of the ray deflection amplifiers, respectively, are the first and second inputs of the device, and the outputs through the beam deflection amplifiers are connected to deflectors using the deflection of the beam, respectively, and respectively. and the second digital-to-analog converters of radius coordinates, the first inputs of which are, respectively, the third and fourth inputs of the device, the trigger trigger, the first input of which is the fifth input the device house, and the output is connected to a pulse distributor, characterized in that, in order to increase the device speed, it contains a waiting generator of sine and cosine voltages, first and second registers, four switches, four multipliers, two adders and an inverter, the first input A sine wave and cosine voltage generator is connected to the first input of the first digital-to-analogue coordinate converter of the radius, the second input is connected to the trigger trigger output, the third input is connected with the output of the pulse distributor, the first output is connected to the second input of the first digital-to-analogue radius coordinate converter, the second output is connected to the second input of the second digital-to-analogue radius coordinate converter, the third output is connected to the second input of the trigger trigger, the inputs of the first and second registers are the sixth and seventh inputs devices, the first inputs of the first and second multipliers are connected to the output of the first register, the first inputs of the third and fourth multipliers are connected to the output second register, the second inputs of the first and fourth multipliers are connected to the output I of the first digital-analogue radius coordinate converter, the second inputs of the second (L and third multipliers are connected to the output of the second digital-analogue converter of radius coordinates, the first input of each switch is connected to the output of the corresponding multiplier, the second inputs of the first and The second switch is connected to the output of the first register, the second inputs of the third and fourth switch are connected to the output of the second register, the first and Secondly, the OS 00 inputs of the first adder are connected respectively to the outputs of the first and third switches, the first and second inputs of the second adder are connected respectively to the outputs of the second and fourth switches, the outputs of the adders are connected to the first inputs of the beam deflection amplifiers, the input of the inverter is connected to the output of the pulse distributor, and the output is connected to a CRT modulator.

Description

The invention relates to digital data output devices on indicator devices, in particular, cathode ray tubes (CRT), and is intended for use in electronic devices displaying graphical information.

The purpose of the invention is to increase the speed of the device.

The drawing shows a structural diagram of the proposed device.

The device contains trigger trigger 1, pulse distributor 2, digital-to-analog converters of radius 3 and 4 coordinates, digital-to-analog converters of center coordinates 5 and 6, beam deflection amplifiers 7 and 8, CRT 9, standby generator of sine-wave and cosine-like stresses 10, first 11 and second 12 registers, multipliers 13-16, switches 17-20, adders 21 and 22, inverter 23.

The standby generator of sinusoidal and cosine voltage 10 includes a switch 24, an adder 25, digital-controlled resistances 26 and 27, integrators 28 and 29, reset keys of integrators 30 and 31, a comparator 32, a two-digit counter 33, a decoder 34.

The device works as follows.

When constructing circles, the cosp and sinp codes are written in the cosine and sine registers And and 12. In this case, the sinp code must be equal to zero, and the cosp code must be equal to one. The coordinate codes of the center of the circle are fed to the input of digital-to-analog converters of the coordinates of center 5 and 6, and the radius code is fed to the first inputs of digital-to-analog converters of coordinates of radius 3 and 4, as well as to the first input of a waiting generator of sine and cosine oscillations 10. After a certain time sufficient for output the electron beam to the center of the circle, the signals from the output of digital-to-analog converters of the coordinates of the center 5 and b, which, through the amplifiers 7 and 8, affect the CRT 9, the signal " A start, in which the output signal of the start trigger 1 starts the pulse distributor 2 and enters the input of the switch 24. The reference voltage through the switch 24 is fed to the input of the adder 25. From the output of the adder 25, the signal passes through the digital-to-analog converter 3, the multiplier 13, the switch 17, The adder 21, the bias amplifier 7, acts on the first input of the CRT 9 and causes the beam to move (without illumination) along the X axis relative to the center of the circle by the radius value. After a time interval sufficient to terminate the transient process when outputting from the center of the circle to the starting point of its construction, a signal is generated at the output of the pulse distributor 2 that controls the opening of the reset keys of the integrators 30

and 31. The same signal, the passage through the inverter 23, acts on the third input of the CRT 9 and causes the beam to illuminate when constructing a circle. When the reset keys of the integrators 30 and 31 are opened, the signals are generated at the outputs of the adder 25 and the integrator 28

X25 U3-r-cos t; eleven

(one)

Y28 Uw-Sin | t,

where TI is the period of harmonic oscillation

signal;

Uji is the reference voltage. The period of the harmonic oscillation of the signal is determined by the radius code and is equal to

T, 2nCR (l + Yes / 2), (2)

where CR is the capacitance and resistance of the integrators 28 and 29, which determine the oscillation period of the signal when constructing a circle with a minimum of 1 radius;

2gai2 is a binary code for the radius of a circle. It can be seen from the above expression (2) that the oscillation period of the signal varies in direct proportion to the code of the radius of the circle.

From the outputs of the adder 25 and the integrator 28, the signals (1) are fed to the inputs of digital-to-analog converters 3 and 4, respectively. At the outputs of these converters, signals are generated

X3 Rcos $ t; eleven

TI

where R is the amplitude value of the harmonic oscillation proportional to the circle.

From the outputs of digital-to-analog converters, signals are fed to multipliers 13-16. At the same time, at the outputs of multipliers 13 and 14, an input signal appears without attenuating its amplitude, since cosp 1 is set in advance when constructing a circle.

At the outputs of the multipliers 15 and 16, the output signal is zero, since sinp O is also set in advance. Switches 17-20 under the action of a sign bit (direct or inverse of registers 11 and 12) change

polarity of the output voltage). As a result, the outputs of the adders 21 and 22 are formed signals

X21 XsoSr,

eleven

Y22 4 cos p R sin | b t.

These signals are fed to the inputs of the amplifiers 7 and 8, the outputs of which

Signals are generated that control the beam of a CRT 9 and provide for the construction of circles, the formation time of which varies in proportion to the code of their radii

X7 X4 + Rcos t,

Yg Yi -t- R.

From the output of the integrator 28, a sinusoidal signal is fed to the input of the comparator 32, which determines the moments of the signal passing through zero. The signal from the output of the comparator 32 is fed to the input of a two-bit counter 33. During one oscillation period, the counter 33 goes into a state that will be deciphered by the decryptor 34. The signal from the output of the decipher 34 sets the trigger of trigger 1 to zero (initial) state, when which blocks the dispensing of impulses of signals b.

When building ellipses, the proposed device works as follows.

The cosp and sinp codes are recorded in registers 11 and 12. The codes for the major (A) and minor (B) ellipse semiaxes are fed to the inputs of digital-to-analog converters 3 and 4, and the coordinate codes of the center of the ellipse to digital-to-analog converters of center coordinates 5 and 6. After time, sufficient for the electron beam to exit to the coordinate point of the center of the ellipse under the action of signals from the outputs of digital-to-analog converters of the center coordinates 5 and 6, a start signal is given, according to which the start trigger 1 output signal starts the pulse distributor 2 and enters the comm 24. The reference voltage through the switch 24 is fed to the input of the adder 25. From the output of the adder 25, a signal passing through the digital-to-analog converter 3, multipliers 13 and 16, switches 17 and 20, adders 21 and 22, deviation amplifiers 7 and 8, affects The first and second inputs of a CRT 9 cause the beam to move (without illumination) to the starting point of the ellipse contour, which is angled relative to the X coordinate of the CRT screen.

At the outputs of the adders 21 and 22, at the moment when the CRT beam reaches the starting point of the ellipse contour, the signals X2I A cosp are formed; Y22-A sinp,

where A is the amplitude value proportional to the greater half-axis of the ellipse.

After a time interval, sufficient to terminate the transient by bringing the beam from the center of the ellipse to the starting point of the ellipse contour, the output of the pulse distributor 2 generates a signal controlling the opening of the reset keys of the integrators 30 and 31. The same signal through

the inverter 23 acts on the third input of the CRT 9 and provides the illumination of the electron beam. When the reset keys of the integrators 30 and 31 are opened, the outputs of the digital-to-analog converters 3 and 4 generate signals

Xs A,

4V.

The voltage at the outputs of the amplifiers 7 and 8 when forming the contour of the ellipse is

X Hz + cosp + sinp Yg Uts sinp + B cosp

From the above expression, it can be seen that these signals applied to the CRT 9 provide for the construction of ellipses oriented relative to the X axis of the screen coordinates at arbitrary angles p. The period of the harmonic signal T; determined by the major axis of the ellipse

T, 2nCR (I -f 2ai2),

where C, R are the capacitance and resistance of the integrators 28 and 29, which determine the period of oscillation of the signal when building an ellipse with a dead .- / smaller semi-axes;

2ai2 - the binary code of the major axis

° ellipse.

From the output of the integrator 28, a sinusoidal signal is fed to the input of the comparator 32, which determines the moments of the signal passing through zero. The signal from the output of the comparator 32 is fed to the input of the counter 33. For one

the oscillation period Ti counter 33 goes to a state that is decoded by the decoder 34. The signal from the output of the decoder 34 sets the trigger of trigger 1 to the zero (initial) state, at which the distributor pulses the 2 signals.

Thus, when constructing circles and ellipses, the device provides a change in the period of the generator of harmonic sinusoidal and cosine oscillations TI is directly proportional to the code of the radius of the circle or to the code of the greater semi-axis of the ellipse. This makes it possible to vary the time of formation of the circles in proportion to the codes of their radii, and the ellipses to the codes of large semi-axes. Speed performance

The proposed device is increased because it is determined by the value inversely proportional to the total time of forming a set of circles with different radii or a set of ellipses with different semi-axes on the CRT screen in one display cycle.

Claims (1)

DEVICE FOR DISPLAYING CIRCLES AND ELLIPSES ON THE ELECTRON BEAM TUBE (CRT) SCREEN, containing the first and second digital-analog converters of the center coordinates, the inputs of which are the first and second inputs of the device, and the outputs through the beam deflection amplifiers are connected to the first and second electron beam deflectors digital-analog converters of coordinates of radius, the first inputs of which are the third and fourth inputs of the device, a trigger, the first input of which is the fifth input three, and the output is connected to a pulse distributor, characterized in that, in order to increase the speed of the device, it contains a standby sine and cosine voltage generator, first and second registers, four switches, four multipliers, two adders and an inverter, and the first input of the standby generator sinusoidal and cosine voltages is connected to the first input of the first digital-analog converter of radius coordinates, the second input is connected to the output of the start trigger, the third input is connected to the output p pulse distributor, the first output is connected to the second input of the first digital-to-analog converter of coordinates of the radius, the second output is connected to the second input of the second digital-to-analog converter of coordinates of the radius, the third output is connected to the second input of the start trigger, the inputs of the first and second registers are the sixth and seventh inputs of the device, the first the inputs of the first and second multipliers are connected to the output of the first register, the first inputs of the third and fourth multipliers are connected to the output of the second register, the second inputs of the first and fourth multipliers are connected to the output of the first digital-analog converter of radius coordinates, the second inputs of the second and third multipliers are connected to the output of the second digital-analog converter of radius coordinates, the first input of each switch is connected to the output of the corresponding multiplier, the second inputs of the first and second switches are connected to the output of the first register, the second inputs of the third and fourth switches are connected to the output of the second register, the first and second inputs of the first sum and are respectively connected to the outputs of the first and third switches, the first and second inputs of the second adder are respectively connected to the outputs of the second and fourth switches, the outputs of the adders are connected to first inputs of beam deflection amplifiers, an inverter input coupled to an output of the pulse distributor, and the output is connected to modulator CRT.