SU622131A1 - Arrangement for shaping symbols on tv receiver screen - Google Patents

Description

one

The invention relates to computing and is intended for use in display devices operating according to a forming raster method. The device can be used in television, in devices for displaying and documenting data displayed on a television screen.

Sign characterization devices are known that contain a serially connected character generator, a shift video recorder, a video amplifier, a line scanning indicator, a line counter, as well as a delay line with a number of outputs corresponding to the number of lines in the character, and a delay shift selector. The input of the character generator is connected to the output of the row counter and in parallel to the first input of the selector, the remaining inputs of which are connected to the outputs of the delay line. The output of the selector is connected to the second input of the video shift.

The closest in technical essence to the invention is a device 2 comprising a switch, a delay unit and a pulse distributor connected in series, a pulse generator and a backlight pulse selector connected to a television receiver, the second

the input of the backlight pulse selector is connected to the output of the character decoder, and the third is connected to the output of the row decoder. A disadvantage of the known devices is

in the absence of the possibility of distinguishing the formed symbols and using them to form characters with a vertical decomposition of a raster, since such structures form only oblique symbols on a horizontally traced raster, while the vertical raster distorts the shape of the characters. This leads to a limitation of the field of application of the device.

The purpose of the invention is to expand the field of application of the device by forming signs with vertical decomposition of a raster. The goal is reached by the fact that

an element NOT, a trigger, an OR element and two clock generators are entered into the device for generating characters. The first inputs of the clock generators are connected to the element NOT connected to the first inputs of the switch, the second inputs of the generators are connected to a trigger connected to the switch, the second inputs of which are connected to the delay unit, and the outputs of the clock generators are connected to the OR element connected

to pulse distributor.

The drawing shows a block diagram of the device. The device contains a switch 1 unit

2delays, element NOT 3, generators 4, 5, cycles, trigger 6, element OR 7, distributor 8 pulses, generator 9 pulses,. the selector 10 lights, the decoder 11 lines, the decoder 12 characters, input tires 13-16, the bus 17 output device.

The device works in the following way.

The launch gate through the input buses 13 is fed directly or through the delay unit 2 to the input of the switch 1. Together with the CMM, the bus 14 directly to the first input of the 4 clock generator and the control input of the switch 1 and through the element NOT

3, in inverse form, the sign of the format of the sign arrives at the first input of the clock generator and the second control input of the switch 1. At the same time on the input bus 15 to the input of the decoder 11 lines and on the input bus 16 to the input of the decoder 12 characters gets the line code and the sign code, respectively.

If the received sign of the format of the sign has a logic level “1, the gate of the scouting input arrives to the input of the trigger 6 installation with a delay introduced by block 2, and at the logic level“ O - without delay. The logical “1” generated at the output of the trigger 6 gives permission to start that clock generator (4 or 5), at the second input of which the logical “1 signal of the format signal is present simultaneously. From the clock generator output, the clock cycles through the OR element 7 pass to the input of the distributor 8 pulses, where at its outputs they are transformed into a stack of sequentially distributed signals, of which 9 pulses are dried on the OR elements in a sequential form to form code combinations of pulses highlight character lines. The number of OR elements is determined by the necessary set of varieties of code combinations from the pulses of highlighting of character strings determined by the graphical drawing on the rectangular grid of the characters required for displaying the alphabet.

The last pulse signal generated by the distributor 8 (the end of the formation of the backlight of the characters) from the output of the distributor is fed to the reset input of the trigger 6 to form a signal to prohibit the generation of oscillator cycles 4.5.

The generated code combinations of the illumination pulses enter the illumination selector, to the control inputs of which from the outputs of the decoder 11 lines and the decoder 12 characters, the control signals of the line number and the generated character are supplied.

Under the influence of these signals, a combination of light pulses corresponding to the 5th row of the selected character formed on the output bus 17 from the backlight selector 10 passes.

The variable format of the characters formed is achieved by changing the period of formation of the illuminations of the rows of characters due to the different frequency of formation

0 cycles by generators 4 and 5, and the frequency of forming the cycles of generator 4 is higher than generator 5. The interval for forming the illumination of character lines when the generators are operating 4.5 is characterized by the expression:

/ zn, ass T zn,

The introduction of new elements and connections in combination with the known ones ensured the device operability both with horizontal and vertical decomposition of the raster.

Along with this, the device has the ability to form characters with

5 in a different format, which allows, first, to use, without additional adjustments, when working with a CRT with a different screen diagonal size, the size of the displayed characters on the screens

0 which is acceptable for each screen, secondly, to provide in the device a significant selection of the generated characters.

For a vertical raster, for example, it is the only kind of coding

5 (highlights) characters, which, in comparison with other types of coding: illumination, flickering, blinking, reverse contrast, with prolonged exposure, the fatigability of the vision of the operator's NIN is less affected.

At the same time, the possibility of forming symbols of various sizes allows, without increasing the hardware volume of the device (input elements of the circuit

5 are implemented in 4-5 logic packages "Logic-2, which practically does not affect the volume of the device) to almost double the range of symbols, which can conditionally be upset as lowercase and uppercase characters. All this favorably distinguishes the claimed device from the known analogs and expands the range of its use.

Claims (3)

1.Patent of France No. 2087887, cl. G 06K 15/20; publish 1972. 2. Krivosheykina R.Yu. and Popovska N.K. A device for forming characters on a television screen. M., Sov. radio 1975, p. 74-76. 3. The author's certificate number 572820, cl. G 06K 15/20, 1976.