JPH0115238B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a key input device on the local side (main body side) of a device having a remote control function using an optical signal. It can be applied to many television receivers, VTRs, and computer input keyboards.

Conventional configurations and their problems Taking the case of a television receiver as an example, a local keyboard is provided on the main unit for inputting commands directly on the main unit in addition to remote control; Several input ports of the microprocessor IC that make up the machine are used to connect them with connection lines, and the inputs of different numbers of connection combinations of the key matrix of these local keyboards are serially transmitted inside the IC. It is converted into a signal and transmitted via a data bus connected to the input/output ports of the IC.

An example of a conventional key input device will be explained with reference to FIG. 1 is a microprocessor, and 2-9 are input/output ports for input using local keys 10-25. 26 is an input port for serial input, to which an output line of a preamplifier 28 for receiving remote control signals is connected. 27 is a light receiving diode for receiving remote control signals, 28
is a preamplifier, and 29 and 30 are power supply lines. The remote control light emitted by the remote control transmitter is transmitted to the light receiving diode 2.
7, amplified by a preamplifier 28, and sent to the microprocessor 1 via an input line 26.
is input. Here that input signal is decoded,
A control signal is sent from the output port 31 to control other circuits. Alternatively, it is applied to other decoders as a serial signal from a data bus connected to the output port 32. On the other hand, local key 10-2
5 inputs are applied to the microprocessor 1 from input/output ports 2 to 9, and are input by the combination of connections at the intersections of these 8 lines by local keys 10 to 25.
The microprocessor 1 directly receives 16 different instructions and sends them to the output port 31 or output port 3.
A control signal corresponding to the input command is output to the second data bus.

This conventional key input device has eight lead wires to connect the ports of the microprocessor 1 and the local keys 10 to 25, and therefore has the disadvantage of requiring a large number of connection wires.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a key input device that can transmit signals from local keys to a microprocessor without using many connection lines.

Structure of the Invention The present invention is characterized by a key matrix encoder that converts input from a plurality of local keys arranged in a matrix into serial signals;
A light emitting element that converts this serial signal into a near-visible light signal, an optical transmission means that transmits this near-visible light signal to a light receiving element that receives a remote control signal, and the output of this light receiving element is input to control the load. The reason is that a control circuit such as a microprocessor is provided.

DESCRIPTION OF EMBODIMENTS FIG. 2 shows a key input device according to an embodiment of the present invention. In this figure, the same parts as in FIG. 1 are given the same numbers and detailed explanations are omitted. The feature of this embodiment is that a key matrix encoder 33, an oscillator 35, a light emitting diode 34 and a light guide 36 are provided, and the optical signal of the light emitting diode 34 is transmitted to a light receiving diode 27 for receiving a remote control signal. There is a particular thing. 10 to 25, 33, 35, and 34 can be constructed with substantially the same circuit as a conventional remote control transmitter. That is, the signals from local keys 10 to 25 are input to the key matrix encoder 33 and are input to any local key 1.
It is converted into a serial signal depending on whether 0 to 25 is operated, and the output is used to control the light emitting diode 34.
is driven and sent out as optical output. This light output is applied via a light guide 36 to a light receiving diode 27 for receiving a remote control signal. However, local keys 10 to 25 and light receiving element 2
7, so the light intensity only needs to be weaker than that of a remote control transmitter, and the power is supplied from the set itself, so no batteries are required, and optical transmission is possible. Since the line is also constant, it can be driven with less power.

Although FIG. 2 shows an embodiment in which a light guide 36, which is a flexible photoconductive wire, is used to guide light to the light receiving diode 27, it is possible to guide the light to the light receiving diode 27, but it is possible to use the light guide 36, which is a flexible photoconductive wire, to guide light to the light receiving diode 27. It can also be configured as a light transmission means by using a transparent material or a material that transmits or reflects near-visible light.

Figures 3 and 4 show specific examples of this. Figure 3 uses infrared reflecting mirrors 37 and 38, and Figure 4 uses a photoconductor 3 made of glass fiber or the like.
9 was used. 40 is the cabinet, 4
1 is an infrared filter.

If the preamplifier 29 is installed in the left-right direction as shown in FIG. 3, the light-emitting diode 34 and the light-receiving diode 27 can be placed in a position where they can be seen through the mirrors 37 and 38. That is, the mirrors 37 and 38 allow the light from the light emitting diode 34 to reach the light receiving diode 27 with one reflection.

As shown in FIG.
may be reached.

Effects of the Invention As described above, according to the present invention, the number of input ports of the microprocessor and the number of connection lines routed between the input/output port of the microprocessor and the local key can be saved, and efficient use can be achieved. can.
Further, the circuit configuration is simple, and the number of input local keys can be increased.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a key input device in a conventional example, Fig. 2 is a circuit diagram of a key input device in an embodiment of the present invention, and Figs. 3 and 4 are cross-sectional views showing the specific structure of the same device. It is a diagram. 10-25... Local key, 33... Key matrix encoder, 34... Light emitting diode, 36... Light guide, 27... Light receiving diode, 1... Microprocessor.

Claims (1)

[Claims] 1. A key encoder that converts input from multiple local keys arranged in a matrix on the side of the remote-controlled main unit into serial signals, a light emitting element that converts this serial signal into an optical signal of near-visible light, and a light-emitting element that converts the serial signal into an optical signal of near-visible light. A key input device comprising a transmitting means for remotely controlling an optical signal of a light beam and transmitting the signal to a light-receiving element that receives the light, and a control circuit for controlling a load using the output of the light-receiving element.