SU1195374A1 - Device for displaying information on screen cathode-ray tube - Google Patents

Description

The invention relates to automation and computing and can be used to display graphic information, as well as curves of painted surfaces.

The purpose of the invention is to improve the accuracy of the display.

Figure 1 presents the block diagram of the device; figure 2 - diagram of the delay unit; on fig.Z - diagrams of the device; figure 4 is a diagram explaining the operation of the delay unit; figure 5 is an example of the image of the curve on the screen of a CRT and its encoding; figure 6 - the state of the cells of the memory block for the image presented in figure 5.

A device for displaying information on a CRT screen (FIG. 1) contains a clock pulse generator ’1, a memory block 2, a register 3, the first 4 and second 5 frequency dividers, a sawtooth voltage personnel generator 6 and a CRT 7, a sawtooth voltage horizontal generator 8 , the first counter 9, the decoder 10, the switch 11, the first element And 12, block 13 delay, the shaper 14 of the video signal, digital-to-analog converter 15, the second counter 16, the group of elements NOT 17, the second element And 18, the third element And 19 and the element 20.

The device works as follows.

The clock pulse generator 1 generates the pulses of the reference frequency

(fig.Z), which arrive at the input of the first counter 9 clocks and the input of the second counter 16 of the delay unit 13. From the bit outputs of the counter 9 clocks is removed, the three-digit binary code of the electron beam horizontal position within one point formed on the CRT screen and fed to the input of the decoder 10. From the overflow output of the same counter, the starting pulses of the first 4-frequency divider are removed. Start-up pulses follow with frequency, and the repetition period determines the size of a point on the CRT screen horizontally.

From the second output of the first frequency divider, the parallel binary code of the point address on the CRT screen is taken horizontally, which is fed to the input of memory block 2. The bit width of this code determines the number of dots on the CRT screen horizontally. From the first output of the frequency divider, the horizontal synchronization pulses are removed, which go to the input of the second frequency divider 5 ’and to start the horizontal generator 8 of the sawtooth voltage;

From the second output of the second frequency divider, the parallel binary code of the point address on the CRT screen is taken vertically, which is fed to the input of the memory unit. The digit capacity of this code determines the number of points on the CRT screen vertically. WITH

, 5 of the first output of the second frequency divider, a frame synchronization pulse is removed, which is fed to the input of the personnel generator 6 of the sawtooth voltage.

2o The deflecting voltages from the outputs of the generators 6 and 8 are fed to the deflecting systems of vertical and horizontal scanning.

25 At the eight outputs of the decoder 10, a cyclic sequence of pulses shifted relative to each other is formed (FIG. 3}. These pulses go to one of the inputs

_From switch 11, to another input of which is fed a three-digit binary code offset dX point horizontally from memory block 2. The values of the horizontal offset codes shown in (Fig. 3) are 0.4,2,0,3

35 This code selects one of the eight. mi pulse signals. C signal

the output of the switch 11 is fed to one of the inputs of the first element X 12 to another input which is from the block

The memory 40 receives a signal, which allows the passage of a pulse from the switch output to the input of the zero setting of the second counter 16, the NOT element 13 of the e-4 $ block and the first control input of the register 3.

On the information input of the register from the memory block, a sign signal is received, a three-digit binary

50 offset offset code point vertically and dot color code. These signals are recorded in the register by a pulse on: stepping from the output of the first And element, which determines the beginning of the formation of a point on the CRT screen.

The second counter 16 counts the pulses from the clock generator E _о , starting from the moment of its installation

3 n

to the zero state by a pulse from the output of the first element AND, As soon as the counter counts eight pulses, units And 18 appear at the inputs of the second element And element 18 gives the unit to the third element And 19. If the recording impulses are in two adjacent cycles E, they coincide (FIG. 4), the delayed pulse does not appear at the output of the element And 19, since the element NOT 20 prohibits the passage of a signal to one of the inputs of the element And 19.

If the recording pulses in the adjacent clock cycles E, are less than 8 clock cycles P _in , for example, are separated by a distance of 6 E _o (FIG. 4), then the delayed pulse will not appear at the output of the element And 19,. since the counter 16 is reset by the newly arrived write pulse and there is no match at the inputs of the And 18 element, which means there is no pulse at the And 18 output of the element. In these two cases, the information in the register is changed by the write pulse.

The pulse signal delay from the output of the element And 19 is fed to the second control input (input zero) register 3 and determines the end of the formation of a point on the screen of a CRT. The characteristic signal shifted in time from the first register is fed to the inputs of the driver 14 of the video signals of the digital-to-analog converter 15 and enables them to work. The input of the video signal shaper receives the time-shifted color code of the point, on the basis of which the video signals are generated that control the operation of the CRT modulator.

The inputs are shifted in time to the inputs of the digital-to-analogue converter, the vertical offset code AU, on the basis of which the pulsed deflection voltage is generated,. arriving at the sign deflection system CRT.

Each point on the screen corresponds to one cell of the memory block 2, in which the three-digit code dX of the horizontal offset, the three-digit code dU of the vertical shift, the sign and the color code of the dot are written. Cell address of the memory block coincides with the position of the point on ec95374 4

CRT wound. The sign is equal to "1" if the point belongs to the displayed curve (plane), and is equal to "O" otherwise.

5 From Fig. 5, it can be seen that the display curve on a CRT screen using a known device (lower) as compared with the curve obtained by the proposed device (upper 10th) has gaps and an inconvenient view. The coordinate grid in figure 5 corresponds to a television raster. Numbers and correspond to the position of a point on the CRT screen and are addresses of memory cells.

A positive effect in the device is achieved due to the additional addressing of points in the line spacing of two adjacent lines of a television raster. This allows you to draw smooth curves, 'circles,

25 color pie charts.

In the proposed device, a screen of 256x256 points is used by additional addressing of points to one of eight positions between two adjacent raster lines. Since the point during the formation of the image can move 1/8 of the distance between two adjacent raster lines horizontally and 35 vertical lines, dense filling of the curve points (figure) occurs. The curve obtained in this way is observed as continuous even at a small distance of the observer from the ^40th screen. Thus, the loss of information between the slings of the television raster does not occur, and the curve has no gaps.

45 Using a 256x256 dot screen with additional addressing in the proposed device is equivalent to a raster with a screen size of 2048x2048 dots. However the volume

⁵⁰ memories for the screen in the size of 2048x2048 taking into account three bits of the color code is 12582912 bits The amount of memory in the proposed device, taking into account three bits for encoding the position of the beam vertically, three bits for coding the position of the beam horizontally, one bit

to set the attribute of belonging

five

1195374

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the points of this curve (figure) and the three bits for color coding is 655360 bits. Thus, the amount of memory in the proposed device is 20 times less than the memory capacity of the known device.

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Claims (2)

1.USTROYSTVO FOR INFORMATION DISPLAY ON SCREEN cathode ray tube (CRT), comprising a clock pulse generator, two series-connected divider chas- Toty first output which are connected to inputs of line and frame sawtooth voltage generators respectively, the outputs of line and frame sawtooth voltage generators are connected to coordinate deflection system CRT, modulator of which is connected to the output of the video signal conditioner, input of the video signal conditioner is connected to the first output of the register, the information input of which is connected to the first output of the memory block, the input of which is connected to the second outputs of the frequency dividers, increase the accuracy of the display, it contains the first counter, the input of which is connected to the output of the clock pulse generator, and the overflow output - to the input of the first frequency divider, the decoder, the input of which is connected to the discharge outputs of the first counter, the switch, whose input is connected to the output of the decoder and to the second, the output of the memory block, the first element I, whose inputs are connected to the output of the switch and the third output of the memory block, and the output to the first control input of the register, the delay unit whose inputs are connected to the output m of the clock pulse generator and the first element I, and the output to the second control input of the register, and a digital-to-analog converter, the input of which is connected with the second output of the register, and the output - K with the sign deflection system of a CRT. 2. Device pop.2, characterized in that the delay unit contains the second counter, the inputs of which are the inputs of the block, and the outputs through the elements of the NOT group and directly connected to the inputs of the second element And the output of which is connected to the first input of the third element And the output of the third element And is the output of the block, and the second input is connected to the output element NOT, the input of which is connected to one of the inputs of the second counter. 1195374 > "1195374 2