JPH0264753A - Teletext receiver and method for coupling memory expansion card - Google Patents

Abstract

PURPOSE:To attain memory capacity extending by a card to which different kind memories are mounted without increasing an address line by connecting the expansion card providing the different kind memory with a common bus line. CONSTITUTION:A teletext processing part 4 and a memory expansion card 7 providing the different kind memory of a RAM 34 and a PROM 37 are connected with a common bus line. Then, through a multiplexer 69 of the processing part 4, the address of the RAM 34 from a CPU 21 for which 20 lines are necessary is time-divided and is transmitted with the 10 lines. On the other hand, for 14 address lines which necessary to access the ROM 37, the 10 address lines for accessing the RAM 34 through the multiplexer 69 and the 4 address lines direct-connected with the CPU 21 not through the multiplexer 69 are used. By the connecting, the number of the address lines are reduced and memory capacity extending can be executed by the expansion card mounting the different kind memory.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a teletext receiving device to which a memory expansion card for page expansion, software expansion, etc. can be connected. It is about the method.

“Prior art” The built-in memory (R
The functions of AM and ROM were predetermined by their capacity. In other words, in order to provide many functions, a large capacity memory is required, but the cost of memory accounts for a large proportion of the total device cost. The model was prepared.

``Problems to be solved by the invention'' Providing a wide variety of models as in the past makes it difficult for manufacturers to manage demand and parts, and from the user's perspective, it is difficult to improve functionality. In order to do this, we had to purchase a different model, which was a lot of waste.

In such a case, the present invention aims to expand the memory by using a card having different types of memory, ROM and RAM.

"Means for Solving the Problems" The present invention provides a teletext processing unit with a memory expansion card that is removably attachable to the teletext processing unit, wherein the memory expansion card is equipped with different types of memories, and these different memories are connected to a common system. A method for coupling a teletext receiver and a memory expansion card, characterized in that the teletext receiver is coupled to the teletext processor via a bus line.

"Example" Hereinafter, one embodiment of the present invention will be described based on the drawings.

First, teletext reception will be explained with reference to FIG. (1
) is an RF modulator for controlling RF double signal switching, (2) is a tuner circuit for tuning and intermediate frequency amplification,
(3) is the video/audio switching control section, (4) is the teletext processing section, (5) is the remote control receiving section, (6) is the remote control, (7
) is a memory expansion card.

The RF modulator (1) is equipped with an RF signal input terminal (8) from a television antenna and an RF signal output terminal (9) for an RF multiplied signal.

The video/audio switching control section (3) includes an audio multiplex decoder (
10), analog switch (11), RGB encoder (12), system microcomputer (13), non-volatile RAM (
In addition to 14), an RGB 21-pin connector (15) and other connectors are provided. The video/audio switching control section (3) also includes a CRT (16) connected to a 21-pin connector (15), a VCR (17) for storing and reproducing video tapes, video cassettes, etc., a stereo, two A display section (18) for Japanese and other data is combined.

The teletext processing unit (4) includes a waveform equalization circuit (19), a teletext data reception IC (20), a CPU (21), a P
(Program) ROM (22), gate 7 L/-1
' (23), Program RAM (24), Nonvolatile RA
M (25), composite processing IC for teletext processing (26),
Gate array (27), ■ (video) RAM (28),
A CG (character generator) ROM (29), a printer I/F (30), an audio signal filter and amplifier (31), a card connector (32), and other connectors are provided. In addition to the card (7), a printer (33) is connected to this teletext processing section (4).

The operation of the above configuration will be explained.

A. First, the video signal path will be explained.

The signal is input from the antenna to the RF modulator (1) via the RF signal input terminal (8), and further sent to the tuner circuit (2). This tuner circuit (2) converts the signal into an intermediate frequency signal and sends it to the video/audio switching control section (3).

(a) When watching general TV broadcasts, switch the analog switch (
11), CRT (1) via the 21-pin connector (15)
6) and displayed on this CRT (16).

(b) When recording on the VCR (17), from the analog switch (11) through the RGB1 line: I-da (12)
Recorded in CR (17).

(C) When sending an RF multiplied signal to an external device other than a VCR.

From the ROB encoder (12) to the RF modulator (
1) and is output from the RF signal output terminal (9).

(d) In the case of teletext, the signal input to the video/audio switching control section (3) is sent directly to the teletext processing section (4).
is sent to the waveform equalization circuit (19). This waveform equalization circuit (1
9), after performing waveform shaping such as ghost removal according to the command from the CPU (21), the teletext data receiving IC (20)
) to generate sampling pulses for data acquisition,
After the data is taken in and subjected to processing such as error correction, it is sent to the program RAM (24) via the CPU (21) and the gate array (23). This program RAM
(24) constitutes a ring buffer, which exchanges and stores new data one after another.

Here, when a certain program is selected by a control signal from a remote control (6), which will be described later, the teletext composite processing IC (
26) and in the V RAM (28) with reference to the CG ROM (29). This VRAM
The data in (28) is from the teletext composite processing IC (26).
) to the video/audio switching control unit (3), and the 21-pin connector (15) of this video/audio switching control unit (3).
The image is then sent to the CRT (16) where the character image is displayed.

(a) For VCR recording of character images, the teletext processing unit (
4) to the RO of the video/audio switching control unit (3).
B! encode = + - da (12) and output it to the VCR (17
).

(f) During RF output of a character image, a signal similarly encoded by the RGB encoder (12) is sent to the RF modulator (1) and output from the RF signal output terminal (9).

(g) When printing character images, V RAM (28
) is output to the printer (33) for printing via the teletext composite processing IC (26), gate array (27), and printer I/F (30).

B. Next, the route of the audio signal will be explained.

(a) R from the antenna via the RF signal input terminal (8)
It is input to the F modulator (1) and then to the tuner circuit (
2) and is sent to the video/audio switching control section (3). This video/audio switching control section (3) has an audio multiplex decoder (
10) to an analog switch (11), where the signal is switched between a general TV broadcast audio signal and a teletext audio signal, which will be explained in (b) below.

(b) Since the teletext audio signal is stored together with the image data in the program RAM (24) of the teletext processing unit (4), it is separated by the teletext composite processing IC (26), The signal is reproduced as an audio signal and sent to the analog switch (11) of the video/audio switching control section (3) via an audio signal filter and amplifier (31).

(C) Either one of the audio signals selected by the analog switch (11) is first sent to the CRT (16) via the 21-pin connector (15), and then sent to the second L knee V
CR (17) and thirdly, the RF modulator (
1) is output from the RF signal output terminal (9).

C0 Next, the route of the control signal from the remote controller (6) will be explained.

A signal from the remote control (6) is received by the remote control receiving section (5) and input to the system microcomputer (13) of the video/audio switching control section (3). This system microcomputer (13)
Then, control as follows.

(a) Send a switching signal to the analog switch (11) to switch between a normal TV broadcast audio signal and a teletext audio signal.

(b) Send a switching signal to the analog switch (11) and combine the video signal from the tuner circuit (2) with the teletext processing unit (
4) Switch the teletext synchronization signal from 4).

(c) Channel selection control of the tuner circuit (2) is performed based on the channel data of the non-volatile RAM (14).

(d) Selection of a teletext program by instructing the CPU (21) via the gate array (23) of the teletext processing unit (4);
Instructs printing, voice control, etc.

(e) Instruct the audio multiplex decoder (10) to
Switch sub.

(f) Control the display by commanding the display section (18).

In the above-mentioned device, the memory expansion card (7) of the present invention has different types of memories, that is, an expansion RAM (34) and an F ROM (37). Here, for example, the expansion RAM (34) is 1M
Byte type, FROM (37) is 16 byte type, and in order to combine these with the teletext processing unit (4), 20 lines and P are required for the address of expansion RAM (34).
14 for address of ROM (37) and other data.

Approximately 50 lines are required including the control line.

The present invention is a method for reducing the number of these lines as much as possible (specifically, to 31 lines). That is, in FIG. 1, a bank switching circuit (67), an address decode (68), and a multiplex (69) are connected to the CPU (21) in order to reduce the number of address buses. Further, a timing generation circuit (70), a timing generation circuit (71), a timing generation circuit (72), a gate (73), a gate (74), etc. are coupled to the CPU (21), and among these, The output from the gate (74) provides the lower address (AO to 89) and upper address (A□. to A1.) in the multiplex (69).
).

In the above configuration, first, the expansion RAM (3
4), the 20 addresses of the expansion RAM (34) are divided into two times and 10 addresses are output in a time-division manner. In other words, the lower address (A - As) is connected to the memory expansion card (75) using a 1° address line (75).
), the upper address (Alo-A) is output to the memory expansion card (7) through the same 10 address lines (75) by switching at the multiplex (69).

Next, to access PROM (37),
Fourteen addresses are required for M (37). The address space of this FROM (37) is the teletext processing unit (4).
) side, time division is performed, and if bank switching data is output to the ROM, a malfunction will occur. Therefore,
In addition to sharing the ten address lines (75) as they are with the expansion RAM (34), the four address lines (76) that do not go through the multiplex (69) are used to connect the memory expansion card (7). output to the side. That is, when accessing the FROM (37) of the memory expansion card (7), the address line (75) used when accessing the expansion RAM (34) is not switched;
The access time is saved by passing the address of U (21) as it is and outputting it.

In this way, the address lines of the expansion RAM (34) are reduced from 20 to 10, and the address lines of the F ROM
Of the 14 address lines in (37), 1o are shared with the address lines of the expansion RAM (34), so a total of 20 lines are omitted. However, the switching control line is
Since the number of lines increases, the number actually becomes 50-20+1=31 lines. In addition, expansion RAM (34), FROM (37)
The memory capacity of is not limited to the example.

"Effects of the Invention" Since the present invention employs the method described above, different types of memories can be mounted on one card, and the number of address lines can be greatly reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram for explaining the combining method according to the present invention, and FIG. 2 is a block diagram of the entire teletext receiving apparatus. (1)...RF modulator, (2)...tuner circuit, (3)...video/audio switching control section, (4)...
・Teletext processing unit, (5)...Remote control receiving unit, (6
)...Remote control, (7)...Memory expansion card,
(8)...RF signal input terminal, (9)...RF signal output terminal, (10)...audio multiplex decoder, (11)
... Analog switch, (12) ... RGB encoder, (13) ... System microcomputer, (14) ...
・Non-volatile RAM, (15)...21 pin connector, (
16)...CRT, (17)...VCRl (18)
...display section, (19) ...waveform equalization circuit, (20)
--- Teletext data reception IC1 (21) ・CP
U. (22)...FROM, (23)...gate array, (24)...program RAM, (25)...non-volatile R
AM, (26)... Composite processing IC1 (2) for teletext broadcasting
7)...Gate array, (28)...VRAM, (
29)...CGROM, (30)...Printer I/
F, (31)...Audio signal filter and amplifier, (
32)...Card connector, (33)...Printer, (34)...Expansion RAM, (37)...FRO
M, (67)... Bank switching circuit, (68)... Address decoding, <69)... Multiplex, (
70) (71) (72)...Timing generation circuit, (75) (76)...Bus line. Applicant Fujitsu General Ltd.

Claims (3)

[Claims] (1) A memory expansion card is removably attached to the teletext processing unit, and the memory expansion card is equipped with different types of memories, and these different memories are connected to the teletext processing unit via a common bus line. A method for combining a teletext receiver and a memory expansion card, characterized in that: (2) A method for combining a teletext receiver and a memory expansion card according to claim (1), wherein the memories of different types are RAM and ROM. (3) The bus line between the teletext processing unit and the memory expansion card uses time-sharing addresses when accessing the RAM, and the RO
3. The method of combining a teletext receiver and a memory expansion card according to claim 2, wherein a part of the address is shared with a RAM address during M access.