JPH0636627B2 - Remote control transmitter - Google Patents

Description

The present invention relates to a remote control transmitter.

[Conventional technology]

An example of a conventional, generally known remote control transmitter is shown in FIG. 3 and explained. In the figure, reference numeral 1 is an oscillation circuit having an oscillation stopping function for generating a reference signal,
2 is a timing generation circuit for inputting a reference signal from the oscillation circuit 1 to generate timing (clock), and 3 is m ×
An n (m, n is a positive integer) keyboard matrix, 4 is a scan output circuit that outputs a scan signal to the keyboard matrix 3, and 5 is a key input circuit that receives the output of the keyboard matrix 3.

Further, 6 is an instruction circuit for determining a key input signal from the keyboard matrix circuit 3 and setting the output timing of the transmission signal, 7 is a first counter for setting the operation sequence of the instruction circuit 6, and 8 is the instruction circuit 6 described above. Is an output circuit that outputs the transmission signal 70 by using the output signal from the input terminal.

The operation of the remote control transmitter in the circuit thus configured will be described with reference to the time chart of FIG.

FIG. 4 is a time chart in the case where the input signal applied to the input terminal 10 of the key input circuit 5 and the scan signal of the output terminal 40 of the scan output circuit 4 are turned on and off by the keyboard matrix 3. .

In the figure, (a) shows an input state of the input terminal 10 of the key input circuit 5, and (b), (c) and (d) show output terminals 40, 50 and 60 of the scan output circuit 4, respectively. , Ie, the scan output signal, (g) to (j) indicate the count values of the counter 7, (e) ha transmission signal 70, (f) indicate the oscillation state of the oscillation circuit 1. Is.

First, in the key input standby state (period A) in which none of the keys of the keyboard matrix 3 is turned on, the key input circuit 5
The state (a) of the input terminal 10 is "H", and the states (b), (c), (d) of the output terminals 40, 50, 60 of the scan output circuit 4 are
Is "L" and the state (e) of the transmission signal 70 is "L", which sets the operation sequence of the instruction circuit 6.
The first counter 7 is in the count initial state as shown in (g) to (i), and the oscillation circuit 1 is in the oscillation stopped state as shown in (f).

The point (α) is when the key of the keyboard matrix 3 is turned on, and at this time, the input terminal 1 of the key input circuit 5
0 detects “L” at the output terminal 40 of the scan output circuit 4, the oscillation circuit 1 starts oscillation, and the first counter 7
Start counting like (g) to (j). According to the order in which the count value of the first counter 7 advances, the instruction circuit 6 determines the key input, selects the transmission signal corresponding to the key input, and outputs the transmission signal 70 from the output circuit 8.
(Fig. 4 (e)) is output (period (B)).

Next, when there is no key input (period (C)), the instruction circuit 6 determines that there is no key input according to the count value of the first counter 7, and the scan output signal is output.
(b), (c), (d) become "L", and the count values (g) to (j) of the first counter 7 are in the initial state (point (β)).

With the above operation, when the key of the keyboard matrix 3 is turned on, the oscillation circuit 1 operates, and when the key is turned off, the oscillation circuit 1 stops the oscillation.

[Problems to be solved by the invention]

By the way, the count value of the first counter 7 for setting the operation order of the instruction circuit 6 and the count value for operating the instruction circuit 6 do not necessarily match.

Therefore, in the conventional remote control transmitter as described above, the count value of the first counter 7 becomes a value other than the count value used for the operation sequence of the instruction circuit 6 due to noise from the outside or the like. In this case, there is a problem that the instruction circuit 6 becomes inoperable and the oscillation circuit 1 may continue to oscillate.

An example of this state will be described using the time chart shown in FIG. 5. The state up to the period (B) is the same as in the case of FIG. 4, but in the state of the period (C), due to noise or the like. A point (γ) is a point at which the count value of the counter 7 is deviated and the count value becomes larger than the count value used for the operation order of the instruction circuit 6. Then, after the point (γ), the instruction circuit 6 becomes inoperable, the oscillation circuit 1 continues to oscillate, and there is a risk that the state of the period (D) cannot be stopped. In other words, there is a danger that the battery will be uselessly consumed and it will become impossible to get out of the state where transmission is impossible.

In order to get out of such a state, it is necessary to turn off the power supply once and then turn it on again to perform the initial setting.

In view of the above points, the present invention has been made to solve such a problem, and an object thereof is to eliminate the drawbacks of the above-described conventional circuit with a simple configuration, and even in a place with a bad environment, noise, etc. , To provide a remote control transmitter that can be used without concern.

[Means for solving problems]

A remote control transmitter according to the present invention counts clocks from a determination circuit that determines a change in input level of a key input circuit and a timing generation circuit, and is reset when the determination circuit determines a change in output level. A second counter is added, and when the second counter finishes counting, the first counter for setting the operation sequence of the instruction circuit is set to a constant count value, that is, the first counter is set. This is set to the initial state.

[Action]

In the present invention, the determination circuit detects a state equal to the state where there is no keyboard input, that is, the state where the first counter malfunctions and the instruction circuit does not operate, and at this time, it is reset when there is a keyboard input. When the second counter is not reset and the second counter reaches the set count value, the first counter is set to the initial state. Therefore, even if the instruction circuit becomes inoperative due to noise or the like. , Its inactive state is released.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a remote control transmitter according to an embodiment of the present invention.

In FIG. 1, the same reference numerals as those in FIG. 3 indicate the same things, 9 is a judging circuit for judging the level change of the signal inputted to the key input circuit 5, and 10 is a clock from the timing generating circuit 2. Is a second counter that is reset when the determination circuit 9 determines that the input level has changed. The second counter 10 is a counter of the oscillation circuit 1 when the count value reaches a set value. Stop the oscillation,
Moreover, the first counter 7 is configured to be set to the initial state.

Next, the operation of the embodiment shown in FIG. 1 will be described with reference to the time chart of FIG.

In FIG. 2, the same reference numerals as those in FIGS. 4 and 5 indicate the same or corresponding waveform portions, and (k) indicates the reset signal to the second counter 10 of the judgment circuit 9. Is the output signal of the set count value of the second counter 10.

First, point (α) is when the key of the keyboard matrix 3 is turned on, and at this time, the input terminal 10 of the key input circuit 5 is "L" of the output terminal 40 of the scan output circuit 4 (see FIG. )) Is detected, the oscillation circuit 1 starts oscillating,
The counter 7 starts counting as shown in FIGS. 2 (g) to (j). Then, the instruction circuit 6 determines the key input according to the order in which the count value of the first counter 7 advances, selects the transmission signal corresponding to the key input, and outputs the transmission signal 70 (see FIG. 2) from the output circuit 8. (e)) is output.

At this time, since the input terminal 10 of the key input circuit 5 inputs the key scan output signal of the key scan output circuit 4 through the keyboard matrix, the determination circuit 9 detects the level change due to the key scan signal, The reset signal (k) is output to the second counter 10.

When the oscillation circuit 1 starts oscillating, the second counter 10
Counting has started, and the count value up to that point is reset by the reset signal (k). That is, each time the level change of the key scan output signal of the key scan output circuit 4 is transmitted to the input terminal of the key input circuit 5 via the keyboard matrix, the second counter 10
Resets the count value up to that point.

At point (γ), when the count value of the first counter becomes larger than the count value used for the operation sequence of the instruction circuit 6 due to noise or the like, the period (D) in FIG. It will be the same. In this state, the instruction circuit 6 becomes inoperative, and the key output signal is not output from the scan output circuit 4, so the signal (k) from the determination circuit 9 remains "L". Therefore, the second counter 10 continues to count, and when the set value is reached, the oscillation of the oscillation circuit 1 is stopped, the count value of the first counter 7 is set to the initial set value, and the period (D ) And the standby state for the period (A). (Refer to point ζ) Further, from the point (γ), the first counter circuit 1 performs an abnormal operation, the scan output circuit 4 outputs an abnormal signal, and the signal (k) from the determination circuit 9 causes the second counter circuit to output. Even if the reset signal is output to 10 and the state such as the period (D) cannot be escaped, normally in a remote control transmitter such as a TV, by stopping the key input, the keyboard matrix circuit Thus, the key input circuit 5 and the scan output circuit 4 are separated from each other, so that the determination circuit 9 does not output the reset signal, and when the second counter 10 reaches the set value, the state of the period (D) is released. The standby state for the period (A) is entered.

In this way, it is possible to eliminate the drawback of the conventional circuit in which transmission is not possible without stopping the oscillation, and it is possible to use it without concern even in a place where there are many noises in a bad environment. it can.

〔The invention's effect〕

As described above, according to the remote control transmitter of the present invention, the determination circuit that determines the level change of the input signal of the key input circuit and the clock from the timing generation circuit are counted without using complicated means. Then
A second counter, which is reset when the determination circuit determines a change in the input level, is added, and when the second counter reaches the set count value, the oscillation circuit is stopped and the operation order of the instruction circuit is increased. First to set
With a simple configuration in which the counter of is set to the initial state, it is possible to eliminate the drawback of the conventional circuit in which transmission cannot be performed without stopping the oscillation, and in a place where there are many noises in a bad environment. Since it can be used without worrying about it, the practical effect is extremely large.

[Brief description of drawings]

FIG. 1 is a diagram showing a remote control transmitter according to an embodiment of the present invention, FIG. 2 is a time chart diagram for explaining the operation of FIG. 1, and an example of a conventional remote control transmitter of FIG. FIG. 4, FIG. 5 and FIG. 5 are time charts for explaining the operation of FIG. 1 ... Oscillation circuit, 2 ... Timing generation circuit, 3 ... Keyboard matrix, 4 ... Scan output circuit, 5 ... Key input circuit, 6 ... Instruction circuit, 7 ... Counter (first
Counter), 8 ... Output circuit, 9 ... Judgment circuit, 10 ... Counter (second counter).

Continuation of front page (56) References JP-A-60-48523 (JP, A) Actual opening 57-104676 (JP, U) Actual opening Sho-60-158248 (JP, U) Actual opening 61-74128 (JP , U)

Claims (2)

[Claims] 1. An oscillator circuit for generating a reference signal, a timing generator circuit for inputting a reference signal from the oscillator circuit to generate a timing signal, and a keyboard matrix of m × n (m and n are positive integers). A scan output circuit that outputs m scan signals to the keyboard matrix, a key input circuit that inputs n outputs of the keyboard matrix, and a key input circuit that determines the key input of the keyboard matrix Instruction circuit for setting the output timing of the transmission signal according to the above, a first counter for counting the timing signal and setting the operation sequence of the instruction circuit, and an output signal from the instruction circuit for inputting the transmission signal. The output circuit for outputting and the signal from the scan output circuit are A determination circuit for determining the level change of the input signal when input to the key input circuit via the board matrix, and counting the clock from the timing generation circuit,
The determination circuit includes a second counter that is reset when a change in the input level of the key input circuit is determined. When the second counter finishes counting, the first counter is turned on. A remote control transmitter characterized by being set to a constant count value. 2. The remote control transmitter according to claim 1, wherein the oscillating circuit stops oscillating when the second counter finishes counting.