JP2563330B2 - Wireless signal transmission method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless transmission method using infrared rays, such as on / off of a key in a wireless keyboard switch, for accurately transmitting data. Is intended to be provided.

2. Description of the Related Art Conventionally, as shown in FIG. 3, a wireless keyboard switch using infrared light transmits two types of data, that is, ON data indicating ON / OFF of a key and OFF data indicating OFF of the key. ing.

In this conventional wireless transmission method, if the OFF data indicating the key is off is not transmitted to the receiving side due to a blocking object crossing the infrared light transmission path as shown in FIG. The state of recognition continues.

To prevent this, as shown in Fig. 5, the transmitting side transmits the data of the turned-on key at regular intervals Ts, and if the receiving side does not send a signal for a time longer than Ts, the key is turned off. By recognizing that it has been turned off, it prevents the erroneous recognition state on the receiving side from continuing indefinitely.

Problems to be Solved by the Invention However, as shown in FIG. 6, when two or more keys are simultaneously pressed, if the OFF data indicating the key OFF is not transmitted to the receiving side, all the keys are turned OFF, False recognition continues until the receiving side recognizes that all keys have been turned off after the time Ts has elapsed after nothing is received by the receiving side.

The present invention solves the conventional problem that erroneous recognition continues on the receiving side, and an object of the present invention is to provide a wireless signal transmission method capable of quickly returning erroneous recognition on the receiving side to normal recognition. It is what

Means for Solving the Problems In order to achieve the above object, the present invention has a buffer for storing data on both the transmitting side and the receiving side, and the address of the buffer in which the data is stored in the data as a transmission signal. And the status of the buffer indicating the usage status of the buffer are sent, and the receiving side identifies the usage status of the buffer on the sending side.

Action The present invention has the following effects by taking the above method. That is, by adding the address of the buffer in which the data is stored to the data sent as a transmission signal by the transmitting side and transmitting the data, the buffer on the receiving side matches the contents of the buffer on the transmitting side. In addition, if the data indicating that the data stored in the buffer on the sending side has been erased is not normally transmitted to the receiving side by sending the status of the buffer indicating the usage status of the buffer as a transmission signal, it is sent to the buffer on the receiving side. You can erase the data that remains.

Embodiment FIG. 1 shows the configuration of an embodiment of the present invention and the format of a transmission signal. The spare in FIG. 1 is for when the number of buffers is increased.

Next, the operation of the embodiment will be described with reference to FIG.
The format of the transmission signal in FIG. 2 uses the format of FIG. When both the key 1 and the key 2 in FIG. 2 are turned off, data is not stored in the buffers on both the transmitting side and the receiving side, which means that the data is empty. In this state, the receiving side buffers A1 to A3 are all empty, so the receiving side recognizes that "all keys are off". Next, when the key 1 is turned on, the transmitting side stores the key 1 on data in the buffer B1 address of the transmitting side buffer B and transmits the signal a. The content of the signal of a is the buffer in which key 1 on data is stored.
This is the address of B1. Upon receiving the signal a, the receiving side stores the key 1 on data in the buffer A1 of the receiving side buffer A. At this time, the receiving side recognizes that the key 1 is turned on. Next, the transmitting side alternately transmits the slave transmission signal b of the status indicating the use state of the buffer B and the key 1 on data a. Since the buffer B1 is in use, the content of the slave transmission signal of status b is set to "1". buffer
Since B2 and B3 are not used, "0" is set. When the receiving side b receives the data, it checks whether the usage statuses of the buffers A1 to A3 are correct. Next, when the key 2 is turned on, since the key 1 on data is already stored in the buffer B1 of the transmitting side buffer B, the key 2 on data is stored in the buffer B2 and the main transmission signal of c is transmitted. Upon receiving this, the receiving side stores the ON data of the key 2 in the buffer A2 of the receiving side buffer A. At this point, the receiving side recognizes that both keys 1 and 2 are turned on. Next, when the key 1 is turned off, the transmitting side transmits the off data d indicating that the key 1 is turned off, deletes the contents of the buffer B1 and puts it in the vacant state. At this time, if the main transmission signal of d is normally received by the receiving side, there is no problem, but if the wireless signal is not normally received by the receiving side due to a blocking object crossing between the transmitting side and the receiving side. On the receiving side, the storage of the key 1 ON data in the buffer A1 is not deleted and remains as it is, so that it is erroneously recognized that both keys 1 and 2 are ON. Next, the transmission side alternately transmits the transmission signal e indicating the status of the transmission side buffer B and the ON data c of the key 2 which is turned ON later. At this time, the slave transmission signal of the status of e is "0" in the buffer B1 because the buffer B1 in which the key 1 is turned off is empty, and "1" in the buffer B2 because the ON data of the key 2 is stored in the buffer B1. Buffer B3 is still empty, so it is set to "0". When the receiving side receives the secondary transmission signal of the status of the buffer of e, it knows that the content of the buffer B1 on the transmitting side is already in an empty state, so it judges that key 1 is off, and only key 2 is on. That will be the correct recognition. Finally, when the key 2 is turned off, the transmitting side transmits the off data f of the key 2 and deletes the storage of the buffer B2 to bring it to the vacant state. When the receiving side receives f, it deletes the storage of the buffer A2 on the receiving side and recognizes that all the keys have been turned off because all the buffers become empty. If the main transmission signal of f is not normally received on the receiving side, it is recognized that all the keys have been turned off from the time point g according to the processing when nothing is transmitted to the receiving side for the same fixed time as in the conventional example.

As described above, according to the above-described embodiment, even if the receiving side is in the incorrect recognition state, it is possible to return to the correct recognition from that point by receiving the status of the buffer transmitted later.

EFFECTS OF THE INVENTION The present invention does not cause an erroneous recognition state on the receiving side to continue indefinitely as is clear from the above embodiment,
It is possible to limit the time when the status of the buffer is modified when it is received and the false recognition continues within a certain time.

[Brief description of drawings]

FIG. 1 is a diagram showing the structure and the format of a transmission signal in one embodiment of the present invention, FIG. 2 is a timing diagram for explaining the actual operation, FIG. 3 is a timing diagram of the transmission signal, and FIG. FIG. 5 is a timing chart for preventing erroneous recognition in the conventional example, and FIG. 6 is a timing chart for erroneous recognition that cannot be prevented in the conventional example. A: receiving side buffer, B: transmitting side buffer.

Claims (1)

(57) [Claims] 1. A buffer for storing key data, a buffer address for identifying the buffer in which the key data is stored, a main transmission signal for transmitting the key data as a pair, and a usage state of the buffer. It is equipped with a transmitter for transmitting two types of slave transmission signals for transmitting the buffer status, a buffer for storing key data at the same address as this buffer address by receiving the main transmission signal, and transmission by receiving the slave transmission signal. A wireless signal transmission method comprising a receiving side capable of identifying the usage state of a buffer on the side.