JPH08321815A - Receiving machine - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve page feed in a receiver for FM text multiplex broadcasting. [Structure] Memory 24 for storing received character data
A display element 50 and a display feed key 62A. When the feed key 62A is operated, it is checked whether or not the character data of the next page in the display element 50 is prepared in the memory 24. As a result of this check,
When the character data of the next page is prepared, the character is displayed on the display element 50 by the character data. When the character data of the next page is not prepared, it waits for the character data of the next page to be prepared for a predetermined period, and when the character data of the next page is prepared in the predetermined period, the character data is prepared. Depending on the data, display element 5
Display a character at 0. When the character data of the next page is not prepared within the predetermined period, the character is displayed on the display element 50 by the character data of the page displayed when the feed key 62A is operated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver for receiving teletext broadcasting.

[0002]

2. Description of the Related Art In FM broadcasting, called "FM character multiplex broadcasting", it has been realized that data such as character information is multiplexed and transmitted together with a program of an original audio broadcasting. Then, the FM character multiplex broadcast is received, and L
FM receivers capable of displaying character information on a display element such as a CD (liquid crystal display element) have been commercially available.

This FM character multiplex broadcasting is capable of mobile reception and is called the DARC system. The standard for multiplexing digital data such as character information is that the subcarrier frequency is 76 kHz, the transmission rate is 16 kbit / sec, and the modulation is performed. The method is LMSK, and the error correction method is a product code based on the (272,190) shortened difference set cyclic code.

There are distinction between levels 1, 2, and 3 as a program service such as character information. All of these are for presenting (displaying) character information etc. by dot display, but Level 1 is a service for receivers that can display 15.5 characters × 2.5 lines including the header part,
Information is text. Level 2 is a service for a receiver capable of displaying 15.5 characters x 8.5 lines including a header part, and the information is characters and figures. Level 3 is a traffic information service for a receiver that can display a detailed map on a CD-ROM, that is, a navigation system.

As the level 1 program service, news, weather forecast, traffic information, entertainment and main complementary programs are considered. In this case, entertainment includes fortune telling, listener message boards,
It provides information such as quizzes and town information.

[0006] Further, the main supplementary program is, for example, when the original audio broadcasting program is a music program, the supplementary information of the program such as the music title, performer name, telephone number / FAX number at the time of request, and the like. It is provided. In the following, main complementary programs are referred to as “program information” or “program-linked”.

Further, as a program service other than the above,
"Urgent information" provided at any time when there is an urgent need
Is also considered.

FIG. 4 shows a frame structure of an LMSK signal multiplexed in the above FM character multiplex broadcasting. One frame of this LMSK signal is composed of 272 blocks,
Each block has 288 bits.

Further, one frame is divided into blocks of 190 data packets and blocks of 82 vertical parity packets, and the blocks of vertical parity packets are distributed and transmitted.

A 16-bit BIC (block identification code) is added to the beginning of each block. However,
Four types of BIC are used, which distinguish each parity packet and identify the beginning of the frame.

The block of the data packet is BI
It has a 176-bit data packet following C, followed by a 14-bit CRC code, followed by 82
It has a horizontal parity check code of bits.

In this case, the CRC code is added to detect the residual error after the error correction by the product code. The block of vertical parity packets is assumed to have a vertical parity packet of 272 bits following the BIC.

Further, each data packet is, as shown in FIG. 5, a 32-bit prefix followed by 144 bits.
And a data block of bits.

As shown in FIG. 6, this prefix is composed of a service identification code, a decoding identification flag, an information end flag, an update flag, a program number, a page number, a data link code, and a data packet number.

The service identification code is 4 bits,
The program content is identified. And level 1
Regarding, "1" is general information for sequential reception processing,
“2” is general information for recording and reception processing, and “4” is traffic information.

In this case, the sequential reception process is a mode in which the decoding process of the presentation is started as soon as the first data packet of the program data or page data arrives at the receiver, and the recording reception process is the program data or Receives and records all page data and CRs for each data group
In this mode, the presented decoding process is started only after the error correction process using the C code is performed.

Then, in the case of a program for which it is necessary to set the timing of presentation on the receiving side on the transmitting side, or for a program which cannot be presented in time if the decoding process is started after the final packet of the data group is obtained, It is a reception process.

The decoding identification flag is 1 bit and is set to "1" when the error correction circuit of the receiver outputs the data by decoding only in the horizontal direction, and the data is decoded after the horizontal and vertical directions are combined. When outputting, it is set to "0".

In the successive reception process, when the decoding identification flag is "0", the receiver receives the first BIC of each data packet and receives the first BIC of the data packet 302 packets after. At this point, it is specified to perform a decoding process for presentation of each data packet.

The information end flag is 1 bit and is set to "1" when the data group to be transmitted with a certain data group number ends, and "0" otherwise.
It is said. Furthermore, the update flag is 2 bits and is incremented by 1 each time the data group is updated. The program number is 8 bits and the page number is 6 bits, and a data group number is formed by both.

Further, since the data link code is 2 bits and the data which should belong to one data group is a large amount of data such that the number of packets exceeds the maximum value of the data packet number, the maximum is possible. It is a code for linking in the order of 0 → 1 → 2 → 3 between the data groups when divided into four data groups and transmitted by the same data group number with different data link codes.

The data packet number excluding the data link code is 8 bits and is assigned in order from "0".

Further, the program numbers are set from 0 to 255, the "total table of contents" is assigned to "0", and "254" is assigned to the main complementary program (program information or program interlocking) as emergency information. “255” is assigned to each.

The page numbers are from 1 to 62,
That is, one program has a maximum of 62 pages. One page corresponds to one data group, and one data group is composed of one or a plurality of data blocks.

At level 1, one page is generally in the display format of 15.5 characters × 2.5 lines,
The display format can be 5.5 characters x 8.5 lines. Also,
In this case, the character data specifies the character to be displayed by the JIS code.

As described above and as shown in FIG. 7, the receiver corresponding to the level 1 is, for example, the LCD 1 having the display screen 1a capable of displaying 15.5 characters × 2.5 lines. . However, the lower left 15 characters x 2 lines portion 1b of the display screen 1a is set as the body text display area, and the upper 0.5 lines and the right half character portion 1c with hatching are set as the header sentence display area. It

The receiver receives the LMSK signal together with the stereo composite signal, decodes the character data from the LMSK signal, and writes the decoded character data in the buffer memory.

Further, the receiver or the remote control transmitter for remotely controlling the receiver is provided with a "general table of contents" key, and by operating this key, the receiver displays as shown in FIG. 8 (A). A general table of contents (main menu) is presented on the screen 1a. However, in FIG. 8A, the total table of contents is displayed over a plurality of pages or in a display format of 8.5 lines, and the first one page or the first 2.5 lines of them is displayed.

Further, the receiver or remote control transmitter is
Further, a "page (screen) advance" key is provided. By operating this key, as shown in FIG. 8B, the display screen 1a displays the next page, or a page with a display format of 8.5 lines. The next two lines of are displayed.

Then, when the user selects and decides the number of the item to be viewed from the total contents, the contents of the selected and decided item are further presented. For example, when the user selects “3. Weather forecast” from the total table of contents, the table of contents such as “1. Today's weather” and “2. Tomorrow's weather” is presented as shown in FIG. .

Further, when the user selects and determines the number of the item to be viewed from the table of contents, the first page of the selected and determined item is presented. For example, when the user selects “1. Today's weather” from the above table of contents, as shown in FIG. 10, specific character information on “Today's weather” is presented.

[0032]

By the way, when an FM character multiplex broadcasting receiver is installed in an automobile, the reception state of the broadcast wave may change significantly as the vehicle travels. In some cases, a state in which the character code cannot be normally received occurs, and it takes a long time to receive all the character codes for one page.

In such a case, for example, even if the key operation for page feed is performed in order to know the weather of the destination, the screen indicating that the process is in progress is displayed forever.

The present invention is intended to solve such a problem.

[0035]

Therefore, in the present invention, a receiving circuit for receiving the character multiplex broadcasting, a memory for storing the character data received by the receiving circuit,
It has a display element and a character display feed key, and when the feed key is operated, it is checked whether or not the memory is provided with the character data of the page next to the currently displayed page. When the character data of the next page is prepared, the character corresponding to the display element is displayed by the character data, and when the character data of the next page is not prepared, the character data of the next page is displayed for a predetermined period. While waiting for the character data of the page to be prepared, when the character data of the next page is prepared in the predetermined period, the character data is used to display the character corresponding to the display element, When the character data of the page of is not prepared within the predetermined period, the character data of the page displayed when the feed key is operated causes It is an receiver so as to display the character corresponding to the child.

[0036]

When the feed key of the display is operated and the character code of the page to be displayed next is completed, that page is displayed. However, when the character code of the page to be displayed next is not completed even after a lapse of a predetermined time, this is notified by a beep sound and the display of the original page is restored.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of a signal system when the present invention is applied to an on-vehicle FM receiver. Further, it is assumed that this FM receiver has a level 1 receiving capability for FM text multiplex broadcasting.

That is, the FM signal received by the antenna 11 is supplied to the synthesizer-type tuner circuit 12 to select a broadcasting station having a target frequency, and the FM signal is converted into an intermediate frequency signal. This intermediate frequency signal is sent to the FM demodulation circuit 1 through the intermediate frequency amplifier 13.
4 is supplied.

In this way, from the demodulation circuit 14, the summed signal (L + R) of the stereo left and right channel audio signals L and R, the DSB signal balanced-modulated by the difference signal (LR), and the pilot signal. And the above-mentioned F
A frequency-multiplexed signal with the LMSK signal in M-character multiplex broadcasting is taken out.

Then, this frequency-multiplexed signal is supplied to the stereo demodulation circuit 15, and the added signal (L + R) and D are added.
Audio signals L and R are demodulated from the SB signal, and these signals L and R are supplied to left and right channel speakers 17L and 17R through amplifiers 16L and 16R.

Further, the FM receiver is provided with a microcomputer 20 for selecting a channel in the tuner circuit 12 and displaying characters by FM character multiplex broadcasting.

That is, this microcomputer 20
Is a CPU 21 for executing the program, and a ROM
22, a RAM 23 for a work area, and a RAM 24 for a reception buffer of data of FM character multiplex broadcasting. In this case, various routines and data for displaying a predetermined character string (sentence) are written in the ROM 22, and a display feed routine 100 shown in FIG. 2, for example, is provided as a part of the routine. .

The memories 22 to 24 are connected to the CPU 21 through the system bus 29, and
The bus 29 has interface circuits (ports) 25 to
28 is connected.

Then, the interface circuit 25 supplies the tuner circuit 12 with data for channel selection, and the channel selection is executed. In addition, the demodulated signal from the demodulation circuit 14
The data in the FM character multiplex broadcast is decoded and taken out from the LMSK signal supplied to the decoder circuit 41, and this data is read through the interface circuit 26 to R
Written in the AM 24, the data in the RAM 24 is constantly updated with the latest data.

The interface circuit 27 is also connected to various operation keys 42 composed of non-lock type push switches, and the key output thereof is taken into the microcomputer 20. Thus, the key 42
If you press any of the keys, the pressed key will
The determination is made by U21, and the process corresponding to the pressed key is executed.

However, when the FM receiver is mounted on a vehicle,
Since the operation panel is narrow and a large number of operation keys cannot be arranged, in this example, the keys 42 are only the keys with high operation frequency and the important keys, and the other operations are remote control (remote operation). ).

Therefore, the receiving circuit 43 of the remote controller is also connected to the interface circuit 27. In this example, the remote controller is of the infrared type, and the receiving circuit 43 includes a light receiving element for receiving infrared rays from the transmitter 60 of the remote controller and a decoder circuit for decoding the remote control signal from this light receiving element. Have and.

Further, the remote controller transmitter 60 is also provided with various operation keys 62 (62A to 62N) constituted by non-lock type push switches. Although a part of the key 62 has the same function as the key 42, when any key of the keys 62 is pressed, data corresponding to the pressed key is formed, and the data is converted into infrared rays to be converted into the FM receiver. Sent to.

In the FM receiver, the transmitter 6
When the infrared ray transmitted from 0 is received by the receiving circuit 43, the original data is taken out and this data is supplied to the interface circuit 27. Thus, the key 42
When the key 62 is pressed, the processing corresponding to the pressed key is performed by the microcomputer 20 as in the case of pressing.
Is executed by In the following, the transmitter 60
The operation of each part will be described depending on the case where the key 62 of is used.

Further, a beep sound signal forming circuit 44 is connected to the interface circuit 28, and the beep sound signal is supplied to the amplifiers 16L and 16R.

Further, the bus 29 is connected with a font ROM (character generator) 31 having font data for converting the character code sent by the FM character multiplex broadcasting into display data, and a display memory. 32 and a display controller 33 are connected, and an LCD 50, for example, is connected to the controller 33 as a display element.

In this case, the LCD 50 is constructed in this example in the same manner as the LCD 1 described above, and is 15.5 characters × 2.
It has a display capacity of 5 lines. The memory 32 is of a bitmap type corresponding to the dot display type of the LCD 50 and has a capacity of one screen. In the following, a teletext program is performed at level 1, and one page has the size (capacity) of one screen.

Then, the character code held in the RAM 24 is read by the CPU 21, the read character code is converted into display data using the font data of the ROM 31, and this display data is stored in the memory 3.
Written to 2. At this time, the controller 33
Thus, the display data in the memory 32 is repeatedly read, converted into a display signal, and supplied to the LCD 50. Therefore, in the LCD 50, the CPU 21
The characters of the character code read from M24 are displayed.

In such a structure, when the page feed key of the keys 62 (or 42) is operated to instruct display of the next page, the CPU 11 executes the routine 100.

That is, assume that an arbitrary character multiplex broadcast program is selected and one page of the program is displayed on the LCD 50. For example, as shown in FIG. 3A, it is assumed that the weather forecast is selected and one page of the weather forecast is displayed on the LCD 50. It should be noted that this display is displayed in the RAM 2 as described above.
The character code of the first page of the selected program, out of the teletext data held in 4, is converted into display data using the font of the ROM 31, and this display data is written in the memory 32. Is realized by

When the page feed key 62A of the operation keys 62 is pressed in such a state, the CP
The process of U11 starts from step 101 of the routine 100, then in step 102, it is checked whether the page currently displayed on the LCD 50 is the last page. If the page is the last page, the process proceeds from step 102 to step 105. Go to, this routine 10
0 ends.

However, when it is not the final page, the process proceeds from step 102 to step 103, and in this step 103, by checking the received data of the RAM 24, the character of the page next to the page currently displayed on the LCD 50 is checked. All code is RAM24
Is checked to see if it was written successfully.

Then, when the data is normally written, the process proceeds from step 103 to step 104,
In this step 104, the LCD is read from the RAM 24.
The character code of the page next to the page currently displayed on 50 is read, and this character code is converted into display data and written in the memory 32.
At 0, the next page is displayed, for example, as shown in FIG. 3C. Then, the process proceeds to step 105, and this routine 100 ends.

Therefore, when the page feed key 62A is pressed, if the character code of the next page is prepared in the RAM 24, the next page is immediately displayed on the LCD 50.

Further, in step 103, the LCD
When all of the character codes of the page next to the page currently displayed in 50 are not yet written in the RAM 24, the process proceeds from step 103 to step 111.
Proceed to. Then, in this step 111, the ROM
The character codes of a predetermined character string are sequentially read from 22 and are converted into display data and supplied to the memory 32. In this way, the LCD 50 displays, for example, in FIG.
As shown in, a character string (text) of "please wait for a while" is displayed.

Subsequently, the process proceeds to step 112, and in this step 112, the timer by software is set. This timer determines the time limit for receiving the next page of data.

Then, in step 113,
It is checked whether or not all the data of the next page has been written in the RAM 24. If not, the process proceeds from step 113 to step 114,
In this step 114, it is checked whether or not the timer set in step 112 has passed a specified time, for example, 1 minute, and if not, the process returns from step 114 to step 113.

Therefore, when the page feed key 62A is pressed and there is no data for the next page in the RAM 24, steps 113 and 114 are repeated until the timer set in step 112 times out, and the next page Wait for all data to be received.

Then, during the period in which the steps 113 and 114 are repeated, that is, the page feed key 62A.
If all the data of the next page can be received within 1 minute after pressing, the process proceeds from step 113 to step 11
5, and in this step 115, the forming circuit 44
Is controlled to output a beep sound from the speakers 17L and 17R, and then the process proceeds to step 104.

Therefore, for example, as shown in FIG. 3C,
The next page is displayed on the LCD 50, and at this time, the fact that the display has been updated is notified by a beep sound. Thereafter, at step 105, this routine 100 is executed.
To end.

In this way, when the page feed key 62A is pressed, even if the character code of the next page is not prepared in the RAM 24, if the character code of the next page is prepared in the RAM 24 within 1 minute, the Page (next page)
Will be displayed on the LCD 50 immediately. At this time, this is notified by a beep sound.

However, when all the data of the next page cannot be received during the period in which steps 113 and 114 are repeated, that is, within 1 minute after pressing the page feed key 62A, the processing is over time, and the process is terminated. The process proceeds from step 114 to step 116. And
In step 116, the forming circuit 44 is controlled to output the beep sound from the speakers 17L and 17R, and then the process proceeds to step 117.

Then, in this step 117, the original page data, that is, the page data displayed on the LCD 50 before this routine 100 is executed is read from the RAM 24, and this character code is read. It is supplied to the memory 32 after being converted into display data.

Therefore, for example, as shown in FIG. 3D,
The page when the page feed key 62A is operated is displayed again on the LCD 50. The processing of the CPU 21 ends the routine 100 in step 105.

Thus, when the page feed key 62A is pressed and the character code of the next page is not prepared in the RAM 24 and the character code of the next page is not prepared in the RAM 24 within 1 minute, the original The page will be displayed on the LCD 50. At this time, this is notified by a beep sound.

Thus, according to this FM teletext broadcast receiver, when the page feed key 62A is pressed and the character code of the next page is prepared in the RAM 24, the next page is immediately displayed on the LCD 50. It

The character code of the next page is RAM2.
If the character code of the next page is prepared in the RAM 24 within 1 minute even if the page is not prepared in 4, the page (next page) is immediately displayed on the LCD 50. further,
When the character code of the next page is not prepared within 1 minute, the original page is displayed on the LCD 50.

Therefore, even if the time until the next page can be displayed is indefinite due to the reception state of the FM character multiplex broadcasting wave, the display "Please wait for a while" during processing does not continue forever. For example, it is not mistaken for a malfunction of the receiver.

When the next page or the original page is displayed after finishing the display during processing, this is notified by a beep sound, so that it is not necessary to pay attention to the screen of the LCD 50.

In the above description, various operations can be performed by the remote controller, but all of these operations can be performed from the key 42 of the FM receiver. In that case, the remote control function may not be necessary. In addition, when the FM character multiplex broadcasting is level 2, one screen has 8.5 lines, of which 8 lines are the body display area. In this case, the character data for 8 lines is divided into 2 lines each. The above-mentioned processing may be performed by dividing the page into 1 and treating it as one page.

[0076]

According to the present invention, even if the time until the next page can be displayed is indefinite due to the reception state of broadcast waves, the display during processing does not continue, and for example, the receiver You can't mistake it for the breakdown.

Further, when the next page or the original page is displayed after finishing the display during processing, this is notified by a beep sound, so that it is not necessary to pay attention to the screen of the display element.

[Brief description of drawings]

FIG. 1 is a system diagram showing an example of the present invention.

FIG. 2 is a flowchart showing an example of the present invention.

FIG. 3 is a diagram showing a display example of the present invention.

FIG. 4 is a diagram for explaining a signal format.

FIG. 5 is a diagram for explaining a signal format.

FIG. 6 is a diagram for explaining a signal format.

FIG. 7 is a diagram for explaining a display screen.

FIG. 8 is a diagram for explaining a display screen.

FIG. 9 is a diagram for explaining a display screen.

FIG. 10 is a diagram for explaining a display screen.

[Explanation of symbols]

 12 tuner circuit 13 intermediate frequency amplifier 14 FM demodulation circuit 15 stereo demodulation circuit 20 microcomputer 21 CPU 22 ROM 23 RAM (for work area) 24 RAM (for reception buffer) 31 font ROM (character generator) 32 memory (for display) 33 Display controller 41 Decoder circuit 42 Operation key 43 Reception circuit (for remote control) 44 Forming circuit (for beep sound signal) 50 Display element 60 Transmitter (for remote control) 62 Operation key 100 Display feed routine

Claims (3)

[Claims] 1. A receiving circuit for receiving a character multiplex broadcast, a memory for storing character data received by the receiving circuit, a display element, and a feed key for displaying a character. The feed key is operated. In this case, check whether the character data of the next page of the currently displayed page is prepared in the memory, and when the character data of the next page is prepared, When the character corresponding to the display element is displayed and the character data of the next page is not prepared, the character data of the next page is waited for a predetermined period and the character of the next page is prepared. When the data is prepared in the predetermined period, the character data displays the character corresponding to the display element, and the character data of the next page is When not provided in the constant period, the character data of the page that was displayed when operating the feed key, receiver so as to display the character corresponding to the display element. 2. The receiver according to claim 1, wherein when the character data of the next page is not prepared, the fact that processing is being performed for a predetermined period is displayed on the display element, and The receiver that waited for the character data of the page to be prepared. 3. The receiver according to claim 1, further comprising a beep sound signal forming circuit, and when the display is changed during the predetermined period or after the predetermined period has elapsed, the forming circuit. The receiver is controlled so that a beep sound is output to notify that the above display has been changed.