JP2002314513A - Data transceiving method in infrared two-way communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data transceiving method in an infrared two-way communication system that prevents stagnation of processing steps on a receiver side when a transmitter side repetitively transmits same data. SOLUTION: According to the method, when the transmitter side repetitively transmits same data in spite of return of an ACK signal from the receiver side to the transmitter side, and number of transmission times of the data reaches a prescribed reference number of times, the reception is terminated and the processing continues to a step that is scheduled next.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission / reception method in an infrared two-way communication system, and more particularly to a processing technique when the same data is repeatedly transmitted from a transmission side.

[0002]

2. Description of the Related Art Infrared two-way communication systems are suitable for transmission and reception within a limited range, and do not require wiring. Therefore, in recent years, they have been adopted in many conference facilities including an international conference hall. .

[0003] This type of conference facility is called an IR (infrared) conference facility. In the IR conference facility, both the chairman's seat (parent machine) and each member's seat (child machine) receive infrared rays as communication means. A light-emitting device is provided to perform a speech request, a speech permission, and a vote for or against, for example.

By the way, a communication error is likely to occur when infrared rays receive strong light such as sunlight or downlight leaking into a room or when the distance between the transmitter and the receiver becomes long. For this reason, for example, data reception confirmation is performed as follows.

Referring to FIG. 4, for example, a speech request signal is output from the slave unit and is received by the master unit.
(Acknowledgement) signal is returned.
Similarly, when the master unit is the sender and the slave unit is the receiver,
The slave unit transmits an ACK signal to the master unit.

[0006] When an ACK signal is received by the slave unit (transmitting side), an ANS (answerback) signal indicating that the ACK signal has been received from the slave unit is further transmitted to the master unit (receiving side). In some cases.

[0007]

If an ACK signal from the master unit does not reach the slave unit for some reason, the slave unit receives the same data until the ACK signal is received. Request signal) repeatedly.

Normally, after the master unit transmits an ACK signal to the slave unit, a next scheduled processing step is performed, for example, a transmission step of checking the progress of the meeting and transmitting a speech permission signal or a speech waiting signal. Move to

[0009] However, if the same data is repeatedly sent from the slave unit as described above, the master unit must continue to receive the data, making it impossible to shift to the next processing step. Challenges arise.

The present invention has been made to solve such a problem, and an object of the present invention is to prevent stagnation of processing steps on the receiving side when the same data is repeatedly transmitted from the transmitting side. To provide a data transmitting and receiving method in an infrared two-way communication system.

[0011]

In order to achieve the above-mentioned object, the present invention comprises an infrared receiver and a light-emitting device, each of which comprises a master unit and a slave unit, one of which is a transmitting side and the other is a receiving side. When the receiving side receives the data transmitted from the transmitting side, the receiving side returns an ACK signal (data reception acknowledgment signal) from the receiving side to the transmitting side, and the ACK signal is not received by the transmitting side. Is a data transmitting and receiving method in an infrared two-way communication system that repeatedly transmits the same data from the transmitting side to the receiving side, wherein the transmitting side transmits the data,
The data is transmitted by adding specific transmission number information indicating the number of transmissions to the data, and the receiving side decodes the transmission number information added to the data, and the transmission number reaches a predetermined reference number. In this case, the above-mentioned transmission processing is repeatedly performed, and the next predetermined processing step is executed.

Separately, the receiving side counts the number of receptions of the same data repeatedly transmitted from the transmitting side, and when the number of receptions reaches the reference number, thereafter, the receiving side transmits the same data. May be performed, and the next predetermined processing step may be executed, thereby achieving the above object.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a master unit 10 and a slave unit 20 for constructing an infrared two-way communication system according to the present invention. In this embodiment, the parent device 10 is for a chairman of an IR conference facility, and the child device 20 is for a member of the council.

Although only one slave unit 20 is shown, a plurality of slave units are actually prepared. Note that, because of the two-way communication, when the slave 20 is on the transmitting side, the master 10 is on the receiving side, and when the master 10 is on the transmitting side, the slave 20 is on the receiving side.

As a basic configuration for implementing the present invention, master device 10 and slave device 20 have a C
PUs 11 and 21 and infrared receivers 12 and 22 are provided. Although not shown, the master device 10 and the slave device 20 are provided with various key buttons for operation.

For example, assuming that the child device 20 is on the transmitting side and the master device 10 is on the receiving side, FIG.
When the data is transmitted from the child device 20 and the parent device 10 receives the data,
The K signal is returned.

However, if the ACK signal does not reach the handset 20 for any reason (in the case of a reception failure), the handset 20 repeatedly transmits the same data. Is transmitted repeatedly, transmission number information is added to the data.

FIG. 2 schematically shows a configuration example of transmission data D per transmission. In this example, the transmission data D is composed of 9 bytes (1 byte, 8 bits), the first to eighth bytes are a data write area, and the number of transmissions n is written in the remaining nine bytes.

This writing is performed by the C
This is performed by the PU 21. CPU 11 of master device 10
When the data is received, the number of times of reception of the same data is known from the number of transmissions n of the ninth byte. The write address of the number of transmissions n may be arbitrary, for example, the first 1
The number of transmissions n may be written in the byte, and the second to ninth bytes may be used as the data write area.

Next, a data transmission / reception method according to this embodiment will be described with reference to the flowchart of FIG.
An example will be described in which a request is made from 0 to the master device 10 for the chair. The slave 20 starts in the transmission mode, and the master 10 starts in the reception mode.

First, the slave unit 20 sets a variable n of the number of transmissions to 1 (step T1), and transmits a speech request signal to the master unit 10 with the transmission number information "n = 1" added (step T1). Step T2). After the transmission, 1 is added to the variable n to obtain "2" (step T3), and then the mode is switched to the reception mode (step T4).

When the speech request signal from the slave device 20 is received by the master device 10 (step R1), the master device 10 reads a variable n of the number of transmissions added to the speech request signal and obtains a reference number k. (3 times in this example) is determined (step R2). In this case, since n = 1 and the determination result is NO, the mode is switched to the transmission mode (step R3), and an ACK signal for reception confirmation is returned to the child device 20 (step R4). Then, the mode is switched to the reception mode again.

The slave 20 determines whether or not the ACK signal has been received (step T5). If the ACK signal can be received, the transmission of the speech request signal is terminated (step T6). If the ACK signal cannot be received, the process returns to step T2, and the same speech request signal is transmitted n = 2 times. To resend.

Then, 1 is added to the variable n to obtain "n = 3".
(Step T3), the mode is switched to the reception mode,
The state is awaiting an ACK signal from master device 10 (steps T4 and T5).

On the master unit 10 side, n = 2 (times) and k = 3
(N), since n ≦ k, the ACK signal is returned to the slave unit 20 again. However, if the ACK signal from the master unit 10 is not received by the slave unit 20 even after the second transmission, the step is repeated. Returning to T2, the same speech request signal as above is retransmitted with the number of transmissions n = 3.

When the master device 10 receives the third utterance request signal, since n = k (= 3), the determination in step R2 is YES, and the ACK signal is not returned to the slave device 20. Then, the processing shifts to the next scheduled processing step (step R5).

In other words, when the same utterance request signal is repeatedly sent from slave unit 20, master unit 10 determines that there is an error in transmission and reception of the ACK signal by limiting the number of times of transmission (three times in the above embodiment). After the determination, as a next processing step, for example, in order to respond to a speech request from the handset 20, the process proceeds to a transmission step of transmitting a speech permission signal or a speech waiting signal by examining the progress of the meeting. This allows
The processing time of master device 10 can be reduced.

As another embodiment, data from the slave unit 20 is repeatedly transmitted without adding the number of transmissions, and it is determined whether or not the data received by the master unit 10 is the same. In this case, the number of receptions of the same data may be counted, and when the number of receptions reaches the reference number, the processing may be shifted to the next scheduled processing step as in the above embodiment.

In each of the above embodiments, the slave unit 20 is set to the transmitting side,
Although the parent device 10 is the receiving side, the CPU 21 of the child device 20
It should be understood that the processing program of the present invention is installed in both the CPU 11 of the master device 10 and the CPU 11.

[0030]

As described above, according to the present invention,
If the same data is repeatedly transmitted from the transmitting side even though the ACK signal is returned from the receiving side to the transmitting side, if the number of transmissions reaches a predetermined reference number, the reception is terminated. By shifting to the next scheduled step, the stagnation of the processing step on the receiving side can be prevented, and the processing time can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a master unit and a slave unit that construct an infrared two-way communication system of the present invention.

FIG. 2 is a schematic diagram showing a configuration example of transmission data employed in an embodiment of the present invention.

FIG. 3 is a flowchart for explaining the operation of the present invention.

FIG. 4 is an explanatory diagram of a conventional data confirmation method between a parent device and a child device.

[Explanation of symbols]

 Reference Signs List 10 parent device 20 child device 11, 21 CPU 12, 22 infrared ray receiver and emitter 12a, 12a infrared ray emitter 12b, 22b infrared ray receiver

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04L 12/28 300 29/08 F-term (Reference) 5K002 AA05 BA14 BA16 CA12 FA03 GA06 5K014 AA02 DA02 FA03 HA09 5K018 AA04 BA03 CA01 FA03 5K033 AA01 AA02 BA02 CB04 DA01 DA20 DB05 5K034 AA02 CC01 DD01 EE01 HH01 HH02

Claims (2)

[Claims] Claims: 1. Both devices have an infrared receiver / receiver, and when one is a transmission side, the other is constructed from a master unit and a slave unit which are reception sides, and the reception side receives data transmitted from the transmission side. Then, an ACK signal (data reception acknowledgment signal) is returned from the receiving side to the transmitting side. If the ACK signal is not received by the transmitting side, the same data is transmitted from the transmitting side to the receiving side. In the method for transmitting and receiving data in an infrared two-way communication system, the transmitting side transmits the data by adding specific transmission number information indicating the number of transmissions to the data, and transmitting the data. Decrypts the transmission count information added to the data, and when the transmission count reaches a predetermined reference count, ignores repeated transmission from the transmission side thereafter. Method of transmitting and receiving data in the infrared bi-directional communication system and executes a predetermined process steps then are scheduled. 2. An apparatus according to claim 1, further comprising an infrared receiver, wherein one is a transmitting side, and the other is constructed from a master unit and a slave unit which are receiving sides, and the receiving side receives data transmitted from the transmitting side. Then, an ACK signal (data reception acknowledgment signal) is returned from the receiving side to the transmitting side. If the ACK signal is not received by the transmitting side, the same data is transmitted from the transmitting side to the receiving side. In the method for transmitting and receiving data in an infrared two-way communication system, the receiving side counts the number of receptions of the same data when the same data is repeatedly transmitted from the transmitting side, and the number of receptions is used as a reference. When the number of times has been reached, the infrared communication system is characterized in that it repeats the subsequent transmission from the transmitting side and executes the next predetermined processing step. Data transmission and reception method in a Temu.