JPH08330993A - Receiver - Google Patents

Abstract

PURPOSE: To improve the display method for emergency information in a receiver for FM teletext broadcasting. CONSTITUTION: A memory 24 where character data received by reception circuits 11 to 14 is stored and a display element 50 are provided. An emergency information key 62A and a circuit 20 which detects emergency information at the time of broadcasting of this information are provided. When emergency information is broadcasted, data of emergency information is stored in the memory 24 in accordance with the output of the circuit 20 which detects this information, and emergency information is displayed on the display element 50 by data of this information. When the emergency information key 62A is operated, emergency information is displayed on the display element 50 again by data of emergency information stored in the memory 24.

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, as described above, the FM text multiplex broadcasting has "emergency information" provided when there is an urgent need.
Is assigned.

However, during the character multiplex broadcasting, the program name of "emergency information" is not included in the general table of contents shown in FIG.
The program name of "urgent information" is not displayed.

Therefore, when emergency information is broadcast,
If another program is displayed even once after the emergency information is displayed, even if the previous emergency information is displayed again, it cannot be displayed.

The present invention is intended to solve such a problem.

[0036]

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,
A display element, an emergency information key, and a circuit that detects the emergency information when it is broadcast. When the emergency information is broadcast, the data of the emergency information is output according to the output of the circuit that detects the emergency information. Is stored in the above memory,
The emergency information is displayed on the display element by this emergency information data, and when the emergency information key is operated, the emergency information is re-displayed on the display element by the emergency information data stored in the memory. This is the receiver.

[0037]

When the emergency information key is operated, the emergency information data stored in the memory is read out, and the read data redisplays the emergency information on the display element.

[0038]

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 tuner circuit 12 of the synthesizer system to select a broadcasting station of 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, a summed signal (L + R) of the stereo left and right channel audio signals L and R, a DSB signal balanced-balanced by the difference signal (LR), and a 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 as a part of the routine, for example, the routines 100 and 200 shown in FIGS. 2 and 3. , 30
0 is provided.

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 to a font ROM (character generator) 31 having font data for converting a character code sent by 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 in this example has the same configuration 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 emergency information is broadcast and received, the microcomputer 20
At, the fact that the emergency information is broadcast is detected from the program number, the CPU 21 executes the routine 100, the data of the emergency information is stored in the RAM 24, and the emergency information is displayed.

That is, when emergency information is received, CP
The processing of U21 starts from step 101 of the routine 100, and next, at step 102, it is checked whether or not the data of the emergency information before that is stored in the RAM 24. If not stored, the processing proceeds from step 102 to step 102. Proceeding to 103, in this step 103, the area for storing the emergency information data is secured in the RAM 24, and then the process proceeds to step 105.

In step 102, the RAM 2
When the data of the emergency information before that is stored in 4, the processing proceeds from step 102 to step 104, and in step 104, of the RAM 24,
The area in which the emergency information before that is stored is cleared, and then the process proceeds to step 105.

Thus, the area for the data of the current emergency information is secured in the RAM 24 regardless of the state when the current emergency information is received.

Then, in step 105,
The received emergency information data is stored in the area of the RAM 24 secured in step 103 or 104, and then, in step 106, a timer defining the retention period of the emergency information data is set. Then, step 1
At 07, the data (character code) currently used for display on the LCD 50 is temporarily saved in the RAM 23.

Next, in step 108, the emergency information data stored in the RAM 24 in step 105 is displayed on the LCD 50 as a character string. In this display, as described above, the emergency information data (character code) held in the RAM 24 is converted into display data by using the font of the ROM 31, and the display data is written in the memory 32. Will be realized.

Then, in step 108, the processing of this routine 100 is terminated.

Thus, according to the routine 100, when the emergency information is broadcast, the latest emergency information data is stored in the RAM 24 regardless of the presence or absence of the emergency information data up to that time.
The latest emergency information is stored in LCD5.
Displayed at 0. The display of the emergency information can be canceled by key operation as described later.

Further, the routine 200 is executed, for example, every 1 ms by interruption, and the data of the emergency information in the RAM 24 is managed.

That is, the processing of the CPU 21 starts from step 201 of the routine 200 by interruption every 1 msec, and then in step 202, the timer set in step 106 of the routine 100 sets a predetermined time, for example, 30 minutes. It is checked if it has passed.

When the time has not passed, the process proceeds from step 202 to step 206, and this routine 200 ends.

However, in step 202, when the timer has passed the specified time of 30 minutes, the process proceeds from step 202 to step 203. In this step 203, is the emergency information being displayed on the LCD 50? If it is checked and it is being displayed, the process proceeds from step 203 to step 206, and the routine 200 ends.

Therefore, the routine 200 does substantially nothing when the prescribed time of 30 minutes has not elapsed since the emergency information was issued and when the emergency information is being displayed.

However, in step 203, the LCD
When the emergency information is not displayed in 50, the process proceeds from step 203 to step 204, in which the data of the emergency information in the RAM 24 is erased, and then in step 205, the step 2
The timer checked by 02 is cleared, after which the routine 200 ends in step 206.

Therefore, when the prescribed time has passed since the emergency information was broadcast and the emergency information is not currently displayed on the LCD 50, the emergency information data in the RAM 24 is erased. In other words, the RAM 24 stores the latest emergency information data for a prescribed time.

On the other hand, when information other than emergency information is displayed on the LCD 50, for example, when an arbitrary FM teletext program is displayed, the emergency information key 62A of the operation keys 62 is pressed. , CPU21 routine 30
0 is executed and the emergency information is displayed again.

That is, when the emergency information key 62A is pressed, the processing of the CPU 21 is performed in step 30 of the routine 300.
Starting from 1, next, in step 302, it is checked whether or not the emergency information is currently displayed on the LCD 50. In this case, since it is not displayed, the process proceeds from step 302 to step 303. And
In step 303, the data currently used for display on the LCD 50 is temporarily saved in the RAM 23.

Next, in step 304, the RAM 2
It is checked whether or not the emergency information data is stored in step 4, and if it is stored, the process proceeds to step 3
From 04 to step 305, in this step 305, the emergency information data stored in the RAM 24 is read, and the emergency information is displayed on the LCD 50 by the read data. Then, thereafter, in step 306, this routine 300 is ended.

In step 304, the RAM 2
When the emergency information data is not stored in 4, the process proceeds from step 304 to step 311, and in this step 311, the character code of the character string prepared in the ROM 22 is converted into the display data by the font data of the ROM 31. The display data is supplied to the memory 32, and the LCD 50 displays, for example, a character string “There is no emergency information”. Then, thereafter, in step 306, this routine 300 is ended.

Further, in step 302, at present,
When the emergency information is displayed on the LCD 50 (including the case where “There is no emergency information” in step 311 is displayed), the process proceeds from step 302 to step 312, and in step 312, step 107 or The data saved in the RAM 23 is read by 303, and the LCD 50 is displayed by the read data.

Therefore, from this point on, the display on the LCD 50 becomes the screen immediately before the step 107 or 303 is executed, that is, the screen immediately before the emergency information is displayed. Then, thereafter, in step 306, this routine 300 is ended.

In this way, according to this FM receiver, when the emergency information is broadcast, the emergency information is displayed immediately, but even if the display of the emergency information is canceled within the specified time. The emergency information can be displayed again.

Further, when the re-display is stopped, the display is returned to the display when the re-display is performed, so that the user's key operation can be reduced. Further, as described above, the usability in an emergency is improved, and in the in-vehicle device, the safety during operation by the driver is improved.
Each time 2A is pressed, the display of the emergency information and the display up to that time are switched. However, a dedicated key for returning from the display of the emergency information to the display up to that time may be provided.

In the above, step 107,
In 303, the data of the displayed screen is R
Although it is assumed that the data is saved in the AM 23, if there is no possibility that the data in the RAM 24 (data of the screen displayed at that time) will be rewritten during the display of the emergency information, the RAM
Being able to identify that data in 24,
This can be used as the display of the original screen when used in step 312. Furthermore, when the emergency information is displayed or re-displayed while receiving the teletext in the successive reception mode, and then the display of the original program is returned to, the screen at the time of returning may be used.

In the above description, various operations can be performed by the remote controller, but all of these operations can be performed by 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.

[0080]

According to the present invention, when the emergency information is broadcast, the emergency information is displayed immediately, and even if the display of the emergency information is canceled within the specified time, the emergency information is displayed. The information can be displayed again.

[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 flowchart showing an 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

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, an emergency information key, and detecting when emergency information is broadcast. When the emergency information is broadcast, the emergency information data is stored in the memory according to the output of the detecting circuit, and the emergency information is displayed by the emergency information data. A receiver adapted to re-display the emergency information on the display element according to the data of the emergency information stored in the memory when the emergency information key is displayed on the element. 2. The receiver according to claim 1, wherein the data of the emergency information in the memory is erased when a predetermined period has elapsed since the data of the emergency information was stored in the memory. Receiving machine. 3. The receiver according to claim 1, wherein when the display of the emergency information is canceled, the display of the program at the time of displaying the emergency information is restored.