JPH11155158A - Electronic exchange - Google Patents

Abstract

(57) [Problem] To provide an electronic exchange which can accurately correct the time of an internal clock at low cost. SOLUTION: A CPU 150 includes a telephone 200 and an INS.
An incoming / outgoing call to / from the network 300 is detected and notified to the correction circuit 140. The correction circuit obtains a time difference between the CLK 130 and the INS time information service 400 in accordance with an instruction from the CPU 150.
The time difference between the INS time information service 400 and the INS time information service 400 is obtained to obtain a correction value. The obtained correction value is divided by n, and is used for time correction of the CLK by dividing it into n times at predetermined time intervals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic exchange, and more particularly, to an electronic exchange capable of automatically correcting a built-in clock.

[0002]

2. Description of the Related Art Electronic exchanges require accurate time management in units of seconds for recording call time, billing information, and the like. For this reason, the electronic exchange has a built-in clock, but its accuracy is not sufficient, and it is necessary to appropriately correct the time.

Conventionally, in an electronic exchange, in order to automatically correct the time of an internal clock, time signal information is periodically obtained from a time signal service network, compared with the time indicated by the internal clock, and based on the result of comparison, the internal time is determined. I am trying to correct the time on the clock.

[0004] Such electronic exchanges include, for example,
JP-A-63-15191 and JP-A-61-124.
No. 177, for example.

[0005]

In the conventional electronic exchange, in order to obtain the time signal information by calling the time signal service of NTT, if the period for correcting the internal clock is shortened, the running cost increases and cannot be ignored. In addition, if the period of time correction of the internal clock is lengthened to reduce running costs, the amount of one correction will increase, and time will be lost or time will be duplicated during correction. There is a problem that the recording of the call time is hindered.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electronic exchange which can accurately correct the time of an internal clock at a low cost.

[0007]

According to the present invention, there is provided an internal clock, and an automatic switching means for automatically correcting the time indicated by the internal clock, and at least one telephone and an electronic exchange connected to the INS network. , The automatic time adjustment means detects an incoming / outgoing call between the telephone and the INS network, determines a correction value of the internal clock using a time information service of the INS network, and divides the correction value into n. The electronic exchange is characterized in that the time of the internal clock is corrected n times at predetermined time intervals.

According to the invention, there is provided an internal clock, and automatic time correction means for automatically correcting the time indicated by the internal clock, wherein at least one telephone and an electronic exchange connected to an INS network have the time. An automatic correcting means for detecting an incoming / outgoing call between the telephone and the INS network; and a first means for storing first time information from the internal clock in response to a detection signal from the detecting means. And an I.S. of the INS network in response to a detection signal from the detecting means.
A second storage unit for storing second time information from the NS time information service, a comparing unit for comparing the first time information with the second time information, and a comparison result of the comparing unit does not match Control means for further storing third time information from the internal clock and third time information from the INS time information service in the first storage means and the second storage, respectively, The first time information and the third
A first time difference from the second time information, a second time difference from the second time information and the fourth time information, and further obtains the first time difference and the second time A calculating means for obtaining a correction value by obtaining a difference from the difference and dividing by a predetermined number n; and a correction executing means for correcting the time indicated by the internal clock n times using the correction value. Is obtained.

Further, according to the present invention, a communication path switch connected to a plurality of telephones, and the communication path switch and the INS
A digital office trunk that interfaces with the network;
A system clock, an INS time data memory for detecting and storing an INS time information service from the INS network via the digital office trunk, and a system clock data memory for temporarily storing the time indicated by the system clock. , An INS time data memory and a system clock data memory to compare values stored therein, and a correction value for calculating a correction value using a predetermined number n based on a comparison result of the difference comparison circuit An arithmetic circuit, a system clock update control circuit that corrects the system clock by n times at predetermined time intervals using the obtained correction value, and a central processing unit that performs sequence control of each unit. An electronic exchange characterized by the following.

[0010]

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

FIG. 1 shows an embodiment of the present invention. The electronic exchange 100 shown in FIG. 1 includes a communication path switch (SW) 110 connected to a plurality of telephones 200,
Digital office trunk (BRT) 12 for interfacing with an NS (Information Network System) network 300
0, system clock (CLK) 130, and BRT 120
INS time data service (MEMI) 141 that receives, detects and stores the INS time information service 400 from the INS network 300 via the INS network 300, and a system clock data memory (MEMS) that temporarily stores the time indicated by the CLK 130
142, a difference comparison circuit (CMP) 143 for comparing values stored in the MEMI 141 and the MEMS 142, and a CM
A correction value calculation circuit (APC) 144 that calculates a correction value using a preset number n based on the comparison result of P143.
, A system clock update control circuit (AC) 145 that corrects n times at predetermined time intervals using the obtained correction value, and a central processing unit (CPU) that controls all the sequences of the electronic exchange 100. ) 150
And In addition, MEMI141 and MEMS1
42, CMP 143, APC 144, and AC 145
Constitutes the correction circuit 140.

Next, the operation of the electronic exchange 100 shown in FIG. 1 will be described with reference to FIGS.

First, the CPU 150 is connected to the electronic exchange 100.
I for any of the phones connected to
When an incoming / outgoing call to the NS network 300 is made, each unit is controlled so as to perform a process according to the flowchart shown in FIG.

That is, the CPU 150 controls the telephone 200
If an outgoing / incoming call between the INS network 300 has occurred, the fact is detected via the communication path switch 110, and in step S21, the time (TS1) indicated by the CLK 130 at that time is stored in the MEMS 142 and , I
The coded INS date / time element (TI1) obtained from the NS time information service 400 is stored in the MEMI 141. The INS date / time element is as shown in FIG. 3, and octets 3 to 8 are binary-coded. Bit 1 is the least significant bit.

Next, the CMP 143 executes step S22.
Then, the time information stored in the MEMI 141 and the time information stored in the MEMS 142 are compared, and when they match (TS1 = TI1), the CPU 150 is notified to that effect. CPU 150
Receives the notification from the CMP 143, determines that the time indicated by the CLK 130 matches the time of the INS time information service 400, and ends the operation.

If the time information stored in the MEMI 141 and the time information stored in the MEMS 142 do not match, the CPU 150 is notified of the mismatch. Thereafter, in step S23, CPU 150 detects an outgoing / incoming call newly generated between telephone 200 and INS network 300, and, as in the previous case,
The time (TS2) indicated by the CLK 130 is stored in the MEMS 142, and the encoded INS date / time element (TI2) obtained from the INS time information service 400 is stored.
Is stored in the MEMI 141.

Next, the CMP 143 performs step S24.
Then, the time differences ΔTI = TI2-TI1 and ΔTS = TS2-TS1 of the system clock are obtained. And APC1
44 is a step S25 at which the correction value ΔT of the CLK 130 is determined based on the difference ΔTI and ΔTS = (ΔTI−ΔTS) /
Find n. Then, the correction value ΔT is output to AC 145.

In step S26, AC 145 corrects the time of CLK 130 using input correction value ΔT. At this time, the AC 145 performs the correction n times at a predetermined time interval. If the correction value ΔT is positive, the time indicated by CLK 130 is
Since it is later than the time of
When the correction value ΔT is negative, the time indicated by CLK
Since the time is ahead of the time of the NS network 300, a subtraction correction is performed.

As described above, in the present embodiment, I
By using the INS time information service 400 of the NS network 300 and performing the correction of the system clock 130 in a plurality of times, the system clock 130 is inexpensive, the amount of one correction is small, and there is no missing or duplicated time. Automatic correction becomes possible.

[0020]

According to the present invention, an incoming / outgoing call between a telephone and an INS network is detected and the INS time information service is used, so that the internal clock can be automatically corrected at low cost. it can.

According to the present invention, the correction of the internal clock is performed by dividing the time into a plurality of times, so that the amount of one correction can be reduced. can do.

[Brief description of the drawings]

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

FIG. 2 is a flowchart illustrating an operation of automatic time correction in the electronic exchange shown in FIG. 1;

FIG. 3 is a diagram showing a configuration of an INS time date time information element.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Electronic exchange 110 Communication path switch (SW) 120 Digital office trunk (BRT) 130 System clock (CLK) 140 Correction circuit 141 INS time data memory (MEMI) 142 System clock data memory (MEMS) 143 Difference comparison circuit (CMP) 144 Correction value calculation circuit (APC) 145 System clock update control circuit (AC) 150 Central processing unit (CPU) 200 Telephone 300 INS (Information Network System) network 400 INS time information service

Claims (3)

[Claims] 1. An electronic exchange connected to at least one telephone and an INS network, comprising: an internal clock; and an automatic time correction means for automatically correcting the time indicated by the internal clock. Detects incoming and outgoing calls between a telephone and the INS network, obtains a correction value of the internal clock using a time information service of the INS network, divides the correction value into n, and performs n times at predetermined time intervals. An electronic exchange, wherein the time of the internal clock is corrected. 2. An electronic exchange, comprising: an internal clock; and automatic time correction means for automatically correcting the time indicated by the internal clock. In an electronic exchange connected to at least one telephone and an INS network, the automatic time correction means Detecting means for detecting an incoming / outgoing call between a telephone and the INS network; first storing means for storing first time information from the internal clock in response to a detection signal from the detecting means; Second storage means for storing second time information from an INS time information service of the INS network in response to a detection signal from the detection means; and storing the first time information and the second time information Comparing means for comparing, and when the comparison result of the comparing means does not match, the first storage means and the second storage further store third time information from the internal clock and the INS time information service. The third Control means for storing time information;
Calculating a first time difference from the first time information and the third time information; obtaining a second time difference from the second time information and the fourth time information; Calculating means for calculating the difference between the time difference of 1 and the second time difference and dividing the difference by a predetermined number n, and correcting the time indicated by the internal clock n times using the correction value An electronic exchange, comprising: 3. A communication path switch connected to a plurality of telephones, a digital office trunk for interfacing the communication path switch with an INS network, a system clock, and the INS network via the digital office trunk. IN from
An INS time data memory for detecting and storing the S time information service; a system clock data memory for temporarily storing the time indicated by the system clock; and a value stored in the INS time data memory and the system clock data memory. A difference comparison circuit to be compared, a correction value calculation circuit that calculates a correction value using a preset number n based on the comparison result of the difference comparison circuit, and a correction value obtained for the system clock. An electronic exchange comprising: a system clock update control circuit for correcting n times at predetermined time intervals; and a central processing unit for performing sequence control of each unit.