JPS58213577A - Receiving device for television text broadcasting - Google Patents

Abstract

PURPOSE:To prevent occurrence of discrepancy in color in the picture, by producing longitudinal addresses of a color memory to be used for reading out color data even in a program of the longitudinal scroll sending mode in response to the longitudinal address of a pattern memory. CONSTITUTION:The output side 23 of a longitudinal direction counter 21 equipped with an input terminal 25 for horizontal synchronizing signals H, an input terminal 26 for vertical synchronizing signals V, and preset terminal 27, outputs longitudinal addresses P of a pattern memory and is connected to the address input side of an address 1/12 ROM22. The output side 24 of the address 1/12 ROM22 outputs longitudinal addresses C of a color memory. Since the counting value of the longitudinal direction counter 21 is prefixed so as to circulate values from 0 (zero) to 215, the value to be counted next to the 215 is 0 (zero) and, since a value 12 is loaded upon the 0 (zero), the value to be counted next to the 215 becomes 12. By utilizing a lateral address in addition to the longitudinal addresses P and C, characters are displayed without any discrepancy in color.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a television teletext receiving apparatus, and more particularly to a television teletext receiving apparatus for displaying a vertically scrolling transmission mode program.

According to the report of the Radio Technology Council in March 1982, television teletext broadcasting is carried out using the method described below.

On the teletext screen, this section is a small section (color block) based on the full-page fixed display page (full display section).
divided into The number of color blocks that make up the entire display section is
A combination of 31 horizontal blocks, 117 stages, and 527 is obtained. The number of pixels constituting a color block is 8 dots horizontally x 112 dots, and the entire display section is composed of 248 dots horizontally x 204 dots vertically, for a total of 50,592 dots. A horizontal row of pixels is called a pattern line, and the entire display section is composed of 204 pattern lines.

All digital data signals (character signals) for teletext broadcasting, such as dot information and control signals obtained by scanning characters and graphic patterns horizontally and decomposing the image into 248 dots per pattern line, are divided into data packets as a unit. The 10th to 2nd scanning line numbers (2738th in even fields) in the vertical blanking period of the television video signal
Each data packet is time-divisionally superimposed on any two scanning lines between 18 (284th H). Data packets include page control packets (PCP) that transmit control signals related to the entire page such as program number and page number, and color code packets (CCP) that transmit color signals that specify coloring, blinking, concealment, etc. for each color block. > ,
Pattern data packet (FDP) that transmits binary digital data obtained by horizontally scanning text and graphic patterns
(the aforementioned one pattern line is included in the PDPI packet), a horizontal scroll data packet (HDP) that transmits a signal for horizontal scrolling, a program index packet (Pl, P ),
There are six types of dummy packets (DMP) that are sent when broadcast data packets cannot be transmitted in the superimposed section. A data packet consists of a header section and an information data section following it. The header section contains a clock run-in signal (CR) for synchronization, a framing code signal (FC) for frame synchronization, and information indicating the type of broadcasting service. Service identification/
It consists of an interrupt signal (SI/IN) and a data identification signal (DI> that indicates the type of data packet), and the information data section consists of pattern data and a control signal.The header section consists of 48 bits and information data. The part consists of 248 bits,
The entire data packet consists of 296 bits.

FIG. 1 is a schematic block diagram showing a conventional television teletext receiving apparatus. In the configuration, the parts constituting an ordinary television receiver include a tuner 2 to which an antenna 1 is connected, and a cathode ray tube 13 via an intermediate frequency amplification circuit 3, a video amplification circuit 16, and an output interface circuit 12.
connected to and configured. In the character signal receiving part, an intermediate frequency amplification circuit 3 is connected to a buffer memory 5 via a sampling circuit 4.
, a buffer memory 5, a central processing unit (CPU) 6 such as a microprocessor, a pattern memory 7, a color memory 8, a program selection device @10, a ROM 14, and a RAM.
15 are connected to each other through a pass line 9, and a continuous control circuit 11 is connected to the pattern memory 7 and color memory 8.
The pattern memory 7 and the color memory 8 are connected to the output interface circuit 12.

In operation, a television signal received by the antenna 11 and superimposed with a character signal is channel-selected by the tuner 2 and converted into a video intermediate frequency, and further amplified and detected by the video intermediate frequency amplification circuit 3 and converted into a video signal. Ru. When receiving normal television broadcasting, this video signal is amplified by a video amplification circuit 16 and driven to a cathode ray tube 13 via an output interface circuit 12. On the other hand, in the case of receiving a teletext broadcast, the character signal superimposed on the video signal is separated from the video signal by the extraction circuit 4, and this character signal is temporarily stored in the -H buffer memory 5.

Since the bit rate of the sent character signal is much faster than the data processing speed of the CPU 6, the buffer memory 5 temporarily stores one packet worth of character signal.
The CPU is used for reading as necessary until the next character signal arrives. Among the stored character signals, the signal of the teletext program selected by the program selection device 110 is read out from the buffer memory 5 by the CPU 6 and subjected to data processing, and the character pattern data is sent to the pattern memory 7 and the color data is sent to the color memory 8. Each is transferred and stored via the pass line 9. The procedure for the CPU 6 to process character signals is stored in the ROM 14, and the RA
M15 is used for temporary data storage and storage during the processing. When one page of data is stored in the pattern memory 7 and color memory 8, the readout control circuit 11 sequentially reads out the stored data and displays the character screen on the cathode ray tube 13 via the output interface circuit 12. Display is performed.

By the way, as a transmission mode for teletext broadcasting, there is a vertical scroll transmission mode in which the character screen sequentially moves from the bottom to the top on the cathode ray tube. In the vertical scroll transmission mode, scrolling is performed in the vertical direction (vertical direction of the cathode ray tube) once per vertical synchronization of the preview signal. However, the text screen is only 1
Move one line at a time from bottom to top in vertical synchronization.

FIG. 2 is an explanatory diagram showing the relationship between the character screen of a cathode ray tube and the number of lines. In vertical scroll sending mode,
A total of 12 lines, line 0 to line 11, are fixedly displayed as a page header.

Scrolling is then performed on the remaining lines. That is, initially, lines 12 to 203 are displayed on the screen, and the remaining lines 204 to 215 are not displayed on the screen as hidden parts. Then, in the next vertical synchronization, line O to line 11 and line 13 to line 204 are displayed on the screen. In other words, line 12 is scrolled. Furthermore, for the next one vertical synchronization, line O
~ Line 11 and Line 14 ~ Line 205 are displayed on the screen. In this manner, in the vertical scroll transmission mode, lines 0 to 11 are fixedly displayed as page headers such as the program name, and the text screen is scrolled in the remaining lines 12 and below.

By the way, as mentioned above, the pattern data and color data are synchronized with the horizontal synchronization signal of the television signal.
They are read out from the pattern memory and color memory, respectively, by the readout control circuit.

The addresses of pattern memory and color memory are divided into addresses corresponding to the vertical direction of the screen (@address) and addresses corresponding to the horizontal direction of the screen (horizontal address), and one address composed of both vertical and horizontal addresses is The stored data is read from each memory,
displayed at the corresponding position on the screen. Generally, a vertical address for reading data is created by counting the horizontal synchronization signal of the television signal, and the clock of a clock generator synchronized with the horizontal synchronization signal of the television signal provided separately is counted. This creates a horizontal address for reading data. As mentioned above, one color block includes 12 vertical lines, so the read address of the color memory is 12 vertical lines (
In other words, it must be the same as the period during which the horizontal synchronizing signal is counted 12 times. That is, generally, the vertical address of the color memory can be obtained by dividing the horizontal synchronizing signal by 1/12 and counting.

However, in the vertical scroll sending mode, the lines are sequentially scrolled as described above, so the frequency division ratio must be changed in accordance with the scrolling. For example, in the case of one-line scrolling, the division ratio of the color block part including the scrolled line is 1/11, and the other parts are 1/11.
12. In the case of two-line scrolling, the division ratio of the color block portion including the scrolled line must be 1/10 and the other parts must be 1/12. In the vertical scroll transmission mode, if the frequency is simply divided by 1/12, the pattern and color data will not match, causing color shift on the screen.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a television teletext multiplexing receiving apparatus that does not cause color shift on the screen even in vertical scroll transmission mode.

To summarize, this invention creates a vertical address of a pattern memory by counting the horizontal synchronization signal of a television signal, adds the vertical address of the pattern memory to an address input of a memory for continuous use, and adds the vertical address of the pattern memory to the address input of a memory for continuous use. By storing the vertical address of the color memory corresponding to the vertical address of the pattern memory added to its address input, it creates the vertical address of the color memory as its output, and uses the pattern when reading program data in the vertical scroll transmission mode. This eliminates mismatch between data and color data.

The above objects and other objects and effects of the present invention will become more apparent from the following detailed description with reference to the drawings.

FIG. 3 is a schematic diagram showing a device for creating a pattern memory vertical address and a color memory vertical address for reading data of a vertical scroll transmission mode program, among the readout control circuits used in carrying out the present invention.

In the configuration, the output side 23 of the vertical counter 21, which is provided with an input terminal 25 for the horizontal synchronizing signal H of the television signal, an input terminal 26 for the vertical synchronizing signal V, and a preset terminal 27, receives the vertical address P of the pattern memory. At the same time, it is connected to the address input side of the address 1/12 ROM 22, and the output side 24 of the address 1/12 ROM 22 outputs the color memory vertical address C.

FIG. 4 is a block diagram showing further details of the vertical counter 21 and its preset terminal 27 shown in FIG. 3.

In the structure, the vertical counter 21 is provided with an input terminal 25 for the horizontal synchronizing signal H and an input terminal 26 for the vertical synchronizing signal V, as described above, and its output side 23 outputs the vertical address P of the pattern memory. . The preset terminal 27 in FIG. 3 is composed of a preset data terminal 34 and a load terminal 39 for loading preset data. The output side of the selector switch 31, which is provided with a CPU terminal 37 and a terminal 38 at the initial stage 11, is the preset data terminal 3.
Connected to 4. Further, the input side of the decoder 32 is connected to the output side of the vertical counter 21, and one output side 36 of the decoder 32 is connected to the switching control input side of the changeover switch 31 and to the input side of the OR gate 33.
The other output side 35 of the decoder 32 is connected to the input side of the OR gate 33, and the output side of the OR gate 33 is connected to the load terminal 39.

In operation, the vertical counter 21 receives the horizontal synchronizing signal H as a clock pulse at the terminal 25, counts it, and outputs a pattern memory vertical address P. On the other hand, the decoder 32 receives and decodes the pattern memory vertical address P, and outputs a pulse to the output terminal 35 at count 11. is loaded with preset data given through terminal 34. The preset data is output from the changeover switch 31, but the changeover switch 31 is normally output from the CPU terminal 37 side (A
)It is connected to the. And from the CPU terminal, first O
preset data is given. This preset data is given from CPtJ, but is held in a latch (not shown). , O even when the preset data is loaded, the count number does not substantially change, so the count continues as 12, 13, etc. At count 203, the vertical synchronization signal V is received at the terminal 26, and the vertical direction Counter 21 is reset to O.

Then, counting is performed again by the clock of the horizontal synchronizing signal H, and at count 11, the preset data is loaded again. After being further reset by the vertical synchronization signal V, preset data of 1 is given from the CPU.

(After that, the preset data increases by 1 each time it is reset, and returns to O again from 215.) In this way, the next 1
Since preset data 1 is loaded when counting 2, the count jumps from 11 to 13.

Then, counting continues, and at count 204, a reset is performed by the vertical synchronizing signal @V.

After this, the count is performed in the same manner as above, 1 to 11.14 to 205, then 1 to 11.15 to 206, etc.
As is clear from FIG. 2, after the count of 1 to 11.24 to 215 is performed, the count of 1 to 11.25 to 2
It needs to be counted as 15.12. This is because, as mentioned above, it is necessary to scroll cyclically in the darkness of 12 to 215 lines. This operation will be explained below.

When the count reaches 215, the decoder 32 outputs a pulse to the terminal 36, whereby the changeover switch 31 is controlled and the switch is temporarily connected to the terminal 38 side (B) at its initial value. The initial value is set to 12 in advance, and 12 preset data is given to the vertical counter 21.

Further, the output pulse of the terminal 36 is applied to the load terminal 39 via the OR gate 33, and 12 preset data are loaded into the next count value. Since the count value of the vertical counter 21 is predetermined to cycle through O-'215, the count value next to 215 is O, and 1 is added to this.
Since 2 is loaded, the count value becomes 12 after all. In this way, 215 is followed by a count of 12. Then, it is reset by the vertical synchronization signal V,
After that, counting from 0 to 11.26 to 215, 12.13 is performed. As described above, the vertical address P for reading the pattern memory for the vertical scroll transmission mode program is created.

Returning to FIG. 3, the stored data for the address 1/12 ROM 22 (which becomes the color memory vertical address) is predetermined as follows. Addresses 0-11 → Data 0° Addresses 12-23 → Data 1. Addresses 24-25 → Data 2. ..., addresses 192-203 → data 16. Address 204-215
→Data is 17.

Then, the pattern memory vertical address P created as described above is given to the address input of the address 1/12 ROM 22, and the stored data is transferred to the output side 2.
4 and output as color memory vertical address C.

For example, the pattern memory vertical address P is...11°1
2.13, 14.15.16.17.18.19.20
．． 21.22.23.24. ..., the color memory vertical address C read from the address 1/12 ROM 22 is ...0.1.1°1.1,1,1,
1, 1, 1, 1, 1.1, 2゜..., and also...
・・11, 13, 14.15.16.17.18.19
,20,21.22,23°24...
・0,1.1.1,1.1.1゜1.1.1,1.1.
2. ...and further...11.14.15.1
6,17,18,19,20゜21.22,23,24
．． In the case of... o, 1゜1.1.1.1.1
．． 1.1, 1.1.2. ...and ...11,1
5, 16.17.1B, 19°20.21, 22, 23
, 24. In the case of...0.1.1.1,1,
1.1, 1.1.1, 2°... As is clear from this, as the lines are scrolled line by line, the division ratios of successive addresses of color data of color blocks including the scrolled line are automatically changed.

Using the pattern memory vertical address P and color memory vertical address C created in this way, and further using the horizontal address created by the method using the general lock generator described above, the apparatus shown in FIG. By configuring the readout control circuit, programs in vertical scroll transmission mode can be displayed without color shift.

As described above, according to the present invention, it is possible to obtain a television teletext multiplexing receiving apparatus that can display programs in vertical scroll transmission mode on the screen without color shift.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram showing the rise and fall of television teletext broadcasting reception, FIG. 2 is an explanatory diagram showing the relationship between the character screen and pattern lines, and FIG.
A schematic diagram showing a device for creating a pattern memory vertical address and a color memory vertical address for reading data of a vertical scroll transmission mode program in the lJ# circuit. FIG. 4 shows the vertical direction counter shown in FIG. 3 and its preset. FIG. 3 is a block diagram showing further details of the terminal. In the figure, 1 is an antenna, 2 is a tuner, 3 is an intermediate frequency amplification circuit, 4 is a character signal extraction circuit, 5 is a buffer memory, 6 is a central processing unit, 7 is a pattern memory, 8 is a color memory, and 9 is a color memory. 10 is a teletext program selection device; 11 is a serial control circuit; 12 is an output interface circuit; 13 is a cathode ray tube; 14 is a ROM; and 15 is a RAM. 16 is a tm image amplification circuit, 21 is a vertical counter, 22 is an address 1/12 ROM 131 is a changeover switch, and 32 is a decoder. Agent Shin Kuzuno - (1 other person) Figure 1 Figure 4 Tower 2 Prisoner hj mouth

Claims (1)

[Scope of Claims] A device that receives character signals for television teletext broadcasting that are transmitted superimposed on the vertical blanking period of a television video signal, and displays a character screen on a display such as a cathode ray tube. The television video signal includes a horizontal synchronization signal and a vertical synchronization signal, and the television teletext broadcast includes at least a program in a vertical scroll transmission mode in which the character screen sequentially moves from bottom to top on the display. , the character signal includes at least pattern data for transmitting character and graphic data, and color data for transmitting data for coloring the character screen, a pattern memory for storing the received pattern data; a color memory for storing the received color data; and a color memory for storing the pattern data and the color data stored in the pattern memory and the color memory, respectively, in order to display the character screen on the display. means for reading in synchronization with a horizontal synchronization signal, the reading means for reading the pattern data of the vertical scrolling transmission mode program in response to the horizontal synchronization signal and the vertical synchronization signal; and means for generating a color memory vertical address for reading the color data of the vertically scrolling delivery mode program in response to the pattern memory vertical address. Receiving device. , (2) The means for creating the color memory vertical address is: adding the pattern memory vertical address to an address input of a memory in which the color memory vertical address is stored as data in advance to create a pattern memory vertical address corresponding to the input pattern memory vertical address. 2. The television teletext multiplexing receiving apparatus according to claim 1, further comprising means for reading out said color memory vertical address.