JPH0662023A - Polling system - Google Patents

Abstract

PURPOSE:To improve polling efficiency by evading the collision of call origination responses to the polling of a master station, stopping the unrequired call origination for fixed time of a terminal equipment after data transmission and eliminating the polling to the terminal equipment not provided with transmission data. CONSTITUTION:Master station transmission polling signals are received at a hybrid circuit 31 and a data reception part 32, data signals are supplied to a reception processing part 33 and also polling signals are supplied to a polling decision processing part 36, a call origination stoppage decision, processing part 37 and a call origination stoppage clear discrimination processing part 40. A timer (1) 38 times random time for arranging the call origination response to the polling and the timer (2) 39 times the time for stopping the call origination for the fixed time immediately after the master station receives the transmission data. Then, the data transmission for which response origination after the lapse of the random time and the call origination suppression for the fixed time after the master station receives response data are performed is performed at a data transmission part 34.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a polling system,
In particular, the present invention relates to a polling method in which a plurality of terminal devices connected in a multi-drop format (branching method) such as a CATV system responds and transmits a data signal to a master station.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a polling method has a master station 20 and a plurality of terminal devices 21-i (i = 1, 1,
2, 3, ... N) are connected in a multi-drop format, and data transfer from the terminal device 21-i to the master station 20 is
As shown in FIG. 4, after receiving the polling signal 5 shown in FIG. 5 from the master station 20, the terminal device 21-i sends out the data signal 16 for the polling.

In FIG. 3, a plurality of terminal devices 21-i for transmitting and receiving data are branched and connected to a data transmission line 22 whose one end is connected to a master station 20.

In this multi-drop type communication system, when data is transferred from each terminal device 21-i to the master station 20, the master station 20 has a timing as shown by an arrow in FIG. The polling signal 5 is transmitted by sequentially performing the polling individually, and the data signal 16 in response to the polling from each terminal device 21-i is received.

That is, an address for specifying each terminal device 21-i is assigned in advance, and as shown in FIG. 4, the master station 20 first sends the polling signal 5 shown in FIG. It is transmitted to the device 21-1.

In FIG. 5, F1 is a plug signal and CTL.
Reference numeral 2 is a control division signal, SPID3 is a call-termination terminal device ID that designates a terminal device for stopping call origination, and BCC4 is an error detection code.

The terminal device 21-which receives this polling
1 sends the data signal 16 shown in FIG. 6 to the master station 20. In FIG. 5, F11 is a flag signal, CTL12 is an information division signal, ID13 is a transmission terminal device ID that specifies a terminal device to transmit, INFO14 is information, and BCC15 is an error detection code.

After receiving the data signal 16 sent from the terminal device 21-1, the master station 20 receives the next terminal device 2
The polling for 1-2 is transmitted, and the terminal device 21-2 returns the data signal 16 for this polling to the master station 20.

Thereafter, in the same manner, the master station 20 becomes the terminal device 2
, 21-n are sequentially executed to receive data signals from the terminal devices 21-3, ..., 21-n.

[0010]

In the conventional polling method described above, the master station 20 sequentially sends polls to each terminal device 21-i, and also polls a terminal device that does not have data. The disadvantage is that the polling time becomes long.

Further, when the power supply of the terminal device is cut off, the polling time becomes longer because of the retransmission.

The object of the present invention is to eliminate the above-mentioned drawbacks, and by eliminating polling to a terminal device which does not have data to be sent, polling efficiency can be significantly improved. To provide a method.

[0013]

According to the method of the present invention, a plurality of terminal devices are connected to a master station via a data line in a branching manner, and the master station collects data by polling. Each terminal device responds to the polling performed by the master station by sending a data signal in response to each other after a lapse of a random time, and stops calling from its own terminal device for a certain time after receiving the data signal by the master station. The data signal is not responded to the polling of the master station until the clear signal for canceling the call suspension from the master station is received or the timeout of the fixed time is reached.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. FIG. 1 shows a configuration of a terminal device according to the present invention. A hybrid circuit 31 for branching and inputting a signal from a master station, and a data reception for receiving a branching input by the hybrid circuit 31 and separately outputting a polling signal and a data signal. A unit 32, a reception processing unit 33 for receiving a data signal, a polling determination processing unit 36 for performing a polling signal determination process, a call termination determination processing unit 37 for performing a call termination determination process for the own terminal, A call-stop-clear determination processing unit 40 that performs a call release cancellation determination process;
A configuration including a timer (1) 38 that measures a random time, a timer (2) 39 that measures a fixed time, a data transmission unit 34 that transmits a data signal, and a transmission processing unit 35 that creates transmission data. Have.

Next, the operation of this embodiment will be described.

The data signal sent from the master station 20 is branched and input by the hybrid circuit 31, and the data receiving section 32 is provided.
Is output to.

The data receiving section 32 separates the polling signal from the master station 20 and a normal data signal, and sends the data signal to the reception processing section 33, which receives and processes it.

On the other hand, the polling signal is supplied to the polling signal receiving section 36, the call stop determination processing section 37 and the clear determination processing section 40.

Upon receiving the polling signal, the polling determination processing unit 36 notifies the data transmission unit 34 and waits for data transmission at random time.
The timer (1) 38 is started.

When the SPID 3 of FIG. 5 which designates the calling stop is received, the timer (2) 39 is started in order to wait the calling for a fixed time.

When the timer (1) 38 and the timer (2) 39 have timed out, the data transmitting unit 34 is notified that the call is released.

The data of the transmission processing unit 35 is sent to the data transmission unit 34, and is transmitted to the master station in the callable time zone at the timing of polling reception from the master station.

FIG. 2 is a diagram showing an example of an operation sequence of the embodiment shown in FIG. The operation of this embodiment will be described in more detail below with reference to FIG.

In FIG. 2, the polling from the master station 20 is first performed by all the terminal devices 21-i (i = 1, 2, 3, ...,
n).

Each of the terminal devices 21-i, when a call request is issued by the terminal device 21-i, indicates the I of the terminal device 21-i shown in FIG.
A timer (1) 3 as a random timer for transmitting a data signal 16 accompanied by D and information to the master station 20 and at the same time determining whether or not to respond to the next polling.
8 is operated.

The data signals 16 from a plurality of terminal devices 21-i arrive at the master station 20, but collisions occur and they cannot be recognized correctly, so the master station 20 polls again.

At this time, each terminal device transmits the data signal 16 to the master station 20 only when it has a data signal to be transmitted and the timer (1) 38 is in the time-out state. To do.

When the master station 20 recognizes another collision, the same polling as described above is repeated, and each terminal device 21-i also repeats.

When the master station 20 receives a data signal from a certain terminal device, it judges that a collision has not occurred, and at the time of transmitting the next polling signal, the call-stop terminal for that terminal device. The polling signal 5 to which the device ID 3 is added is transmitted.

The terminal device corresponding to the call termination terminal device ID3 does not make a call for a certain period of time, and the terminal device that does not correspond to the call suspension does the same operation as before.

At the time of initial startup of the master station 20,
When the terminal device 21-i is initialized, the master station 2
0 is C of the polling signal 5 for the terminal device 21-i.
A clear signal for canceling the call origination stop is transmitted with meaning by TL2 and SPID3.

In FIG. 2, t1-1 and t2- are also shown.
1, t3-1, etc. each have the above-mentioned data to be transmitted, and indicate a state in which the timer (1) 38 can call out due to a timeout, and at t2-2, the data signal of the terminal device 21-2 is The fixed time is indicated by the timer (2) 39 which is received by the master station 20 and is designated by the master station to prohibit calling.

In this way, it is possible to avoid the collision of the response call to the polling of the master station 20 and to secure the polling in which the unnecessary repetition of the data response transmission is significantly suppressed.

In the above-described embodiment, each terminal device is not divided into a plurality of groups, but whether or not to divide into a plurality of groups is determined by determining the collision time due to simultaneous call origination. It can be arbitrarily determined in consideration of the requirements.

[0036]

As described above, according to the present invention, a plurality of terminal devices operated by the polling method call the master station after a random time has elapsed in response to polling of the master station, and the accepted terminal device is By not issuing a call again until a clear signal is received from the master station or a timeout occurs in the own terminal device for a certain period of time, call collision on the transmission path can be avoided and polling efficiency can be significantly improved. There is an effect.

Further, the master station does not need to resend the polling to the terminal device whose power is cut off, so that the polling efficiency can be further improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing an example of an operation sequence of the embodiment of FIG.

FIG. 3 is a block diagram showing a basic configuration of a polling method.

FIG. 4 is a diagram showing an operation sequence of FIG. 3;

5 is a data format of a polling signal in the embodiment of FIG.

6 is a data format of a data signal in the embodiment of FIG.

[Description of Reference Signs] 5 Polling signal 6 Data signal 31 Hybrid circuit 32 Data receiving unit 33 Reception processing unit 34 Data transmission unit 35 Transmission processing unit 36 Polling determination processing unit 37 Call termination determination processing unit 38 Timer (1) 39 Timer ( 2) 40 call stop clear judgment processing unit

Claims (1)

[Claims] 1. A polling method in which a plurality of terminal devices are connected to a master station via a data line in a branching manner, and the master station collects data by polling, in the polling method, each of the plurality of terminal devices performs polling performed by the master station. , The data signal is transmitted as a response after a random time has passed, and the call from the own terminal device is stopped for a certain time after the data signal is received by the master station, and the call from the master station is stopped. A polling method, wherein the response of the data signal to the polling of the master station is not performed until the reception of a clear signal to be released or the timeout of the fixed time.