JP3416195B2 - PB signal transmission method of private digital electronic exchange - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transmitting a PB signal of a private digital electronic exchange used in a private digital electronic exchange. 2. Description of the Related Art Conventionally, private branch exchanges have been
As shown in FIG. 8, the signal is transmitted by a common PBOST.
(PB sender trunk). FIG. 8 is a block diagram for explaining a conventional PB signal transmission method of a private digital electronic exchange. In FIG. 8, 1 is an extension telephone, 2 is an extension circuit (LC), 3 is a switch circuit (SW), 4 is a central office trunk (COT), and 6 is a PB signal circuit (PBOS).
T) and 7 are a central processing unit (CC), and 8 is a main memory (MM). In this type of private digital electronic exchange, if it is attempted to transmit PB signals to a local line or the like more than the number of PB signal circuits 6 at the same time, it is necessary to wait until the PB signal circuit 6 becomes empty. You have to give up sending. This is a so-called block state. To solve such a situation, Japanese Patent Laid-Open Publication No. Sho 59-66290 proposes a system in which a PB sender is provided in the line trunk 4 for each line. Further, as shown in a block diagram for explaining a method of transmitting a PB signal in another conventional private digital electronic exchange of FIG. 9, PB signals are assigned in correspondence with one type of PB signal per address. Japanese Patent Laid-Open No. 63-271 discloses a method of transmitting a PB signal to a large number of office lines at the same time by controlling the channel memory by the channel control memory.
No. 91 proposes this. However, in a system having a PB sender in the office trunk 4 for each office line, the cost of the office trunk 4 is increased, and one type of PB per address is required. In the method of allocating signals to the channel memory and simultaneously transmitting PB signals to a large number of office lines, all types of PB signals (“0” to “9”, “*”, “#”, “A” to
"D") unconditionally requires 16 addresses,
The number of extensions and office lines that can be accommodated is limited by the total number of addresses of the communication path memory, and the extension and office line capacity is reduced accordingly. In particular, in private branch exchanges of small and medium capacity, the number of extensions and office lines that can be accommodated in the exchange must be reduced. In view of the above problems, the present invention has no restriction on the number of simultaneously transmitting station lines for PB signals and reduces the ratio of addresses allocated to PB signals to all addresses in a speech path memory. It is an object of the present invention to provide an inexpensive digital electronic exchange with a PB signal transmission system. According to the present invention, there is provided a method for transmitting a PB signal of a private digital electronic exchange, wherein a plurality of types of PB signals are allocated to one address of a communication path memory, and a dial number to be transmitted to an office line is assigned. writing sequentially the speech path memory a plurality of types of PB signals assigned to one address of the speech path memory at a predetermined time interval that meets the minimum transmission time of each digit, prior to
When a request for transmitting the PB signal is generated , the communication path information is synchronized with the fixed time interval and based on the dial number.
The timing at which the content of the address for reading the PB signal written in the memory is rewritten in the channel control memory, and the PB signal corresponding to the called party dial number is written in the channel memory. , The PB signal
Supplying a predetermined time slot on the highway exit reads from the speech path memory address for reading, also when the PB signal is timing that is not written in the speech path memory, then the PB signal After delaying the reading until the timing of writing to the channel memory, the data is read from the channel memory and supplied to a predetermined time slot on the output highway, and the PB signal is transmitted to the office line requested to be transmitted. is there. According to the present invention, a plurality of types of PB signals are assigned to one address of the communication path memory, and the communication path memory is provided at a predetermined time interval which satisfies the minimum transmission time of each digit of the dial number to be transmitted to the office line. sequentially written into the speech path memory a plurality of types of PB signals assigned to one address of the delivery request of the PB signal is generated, before in synchronization with the predetermined time interval
Write to the call path memory based on the dialed number
Talk about the contents of the address to read the PB signal
When the PB signal corresponding to the called party's dial number has been written to the channel memory, the PB signal is read immediately .
Address is read from the channel memory and supplied to a predetermined time slot on the outgoing highway. If the PB signal has not been written to the channel memory, then the PB signal is After the reading is delayed until it is written into the channel memory, the data is read from the channel memory and supplied to a predetermined time slot on the outgoing highway, and the PB signal is transmitted to the office line requested to be transmitted. Therefore, when a PB signal is to be sent to a local line at the same time, no block occurs and
There is no limit on the number of office lines for simultaneous transmission of B signals, and the ratio of addresses to which PB signals are allocated to all addresses of the speech path memory can be reduced, so that the effective use of extensions and office lines that can be accommodated in the exchange is achieved. be able to. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A PB signal transmission system of a private digital electronic exchange according to an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals and symbols as those in the conventional example denote the same or corresponding components as those in the conventional example. FIG. 1 is a block diagram for explaining a PB signal transmission system of a private digital electronic exchange according to an embodiment of the present invention, and FIG. 2 is a detailed configuration diagram of a switch circuit in FIG. In FIG. 1, 1 is an extension telephone, 2 is an extension circuit, 3 is a switch circuit, and 4 is a trunk. 5
a, 5b, 5c,... 5o, 5p are PB signal generation circuits (PBGEN0 to PBGEND), 5a is a PB signal "0", 5b is a PB signal "1", and 5c is a PB signal "2". , 5d generate the PB signal “3”,... 5o generate the PB signal “C”, and 5p generate the PB signal “D”. .. 6h are PB signal switch circuits (PBSW1 to PBSW8), which sequentially switch PB signals generated by the PB signal generation circuits 5a to 5p at a constant period to be described later, and supply them to the switch circuit (SW) 3. . In this embodiment, two PB signal generating circuits 5a, 5a,
This shows an example in which 5b, 5c, 5d,... 5o, 5p are switched. The PB signal switch circuit 6a outputs the PB signal “0” generated by the PB signal generation circuits 5a and 5b, respectively.
And the PB signal "1" are alternately switched and supplied to the switch circuit 3. Similarly, the PB signal switch circuit 6b supplies the PB signals "2" and "3",... The PB signal switch circuit 6h supplies the PB signals "C" and "D" to the switch circuit 3, respectively. Reference numeral 7 denotes a central processing unit, and reference numeral 8 denotes a main memory. As shown in detail in FIG. 2, the switch circuit 3 includes a multiplexing circuit (MPX) 11, a demultiplexing circuit (DMPX) 12, a communication path memory (SPM) 13, and the communication path memory 13 Channel control memory (C
M) 14. The channel memory 13 is connected to the multiplexing circuit 11 through the input highway 15 and
Through the output highway 16 to the demultiplexing circuit 12,
Each is connected. The control of the communication channel memory 13 is as follows.
In this embodiment, a sequential write / random read control method is used. That is, the data time-division multiplexed by the multiplexing circuit 11 is transferred to the time slot t1 on the incoming highway 15.
To tn in the order of addresses # 1 and # 2 of the channel memory 13.
... On the other hand, at the time of reading, the data is sequentially read from the address specified by the memory content of each address of the communication path control memory 14. by this,
The incoming highway 15 and the outgoing highway 16 exchange data in the same time slot number. In other words, time slot conversion is performed. Further, the multiplexing circuit 1
1 are connected to the PB signal switch circuits 6a to 6h, so that the signal data DSa, DSb,... DSh from each of the PB signal switch circuits 6a to 6h are time-division multiplexed and supplied to the input highway 15. And predetermined addresses #Sa and # in the communication path memory 13 in the order in which they are supplied.
Written in Sb ... FIG. 3 is an explanatory diagram showing the data contents of the signal data supplied from the PB signal switch circuit to the multiplexing circuit in FIG. 1. The signal data supplied from the PB signal switch circuits 6a to 6h to the multiplexing circuit 11 is shown in FIG. DSa, DSb,
.. Indicates the data contents of DSh. PB signal generating circuits 5a and 5b are connected to the PB signal switching circuit 6a, and PB signals "0" and "PB" generated by the PB signal generating circuits 5a and 5b, respectively.
Since the signal "1" is alternately switched at regular intervals, the PB
The signal data DSa supplied from the signal switch circuit 6a to the multiplexing circuit 11 is signal data that repeats PB signal data DP0 and PB signal data DP1 generated by the PB signal generation circuits 5a and 5b, respectively, at a fixed period. The following P
Since the relationship between the B signal switch circuits 6b, 6c,... 6h and the PB signal generation circuits 5c, 5d,... 5p is the same, the signal data DSb is a repetition of the PB signal data DP2 and the PB signal data DP3. Data DSc is a repetition of PB signal data DP4 and PB signal data DP5. Each of the PB signal switch circuits 6a to 6h
Of the PB signal data is simultaneously controlled by the central processing unit 7, and the PB signal data of all the PB signal switch circuits 6a to 6h are switched.
The switching timing of the signal data is synchronized. At this time, the PB signal data supplied to the multiplexing circuit 11 at the same time is put together and the PB signal data DP0, DP2, DP4, DP6, DP8, DP *, D
PA and DPC are “PB signal group 1”, PB signal data DP
1, DP3, DP5, DP7, DP9, DP #, DP
B and DPD are referred to as “PB signal group 2” for convenience and “PB signal group 2”.
The periods during which the “signal group 1” and the “PB signal group 2” are supplied to the multiplexing circuit 11 are referred to as “PB signal group 1 transmission timing” and “PB signal group 2 transmission timing”, respectively. The switching cycle of the PB signal data of the PB signal switch circuits 6a to 6h in this embodiment is 100
mS. P of the PB signal switch circuits 6a to 6h
The switching cycle of the B signal data is determined by the electrical conditions of the PB signal transmitted to the office line, for example, the signal duration is 50 ms or more, the minimum pause is 30 ms or more, and the cycle is 120 ms or more. Further, in this embodiment, in order to synchronously control the switching timing of the PB signal data, when a PB signal is transmitted to a certain station line, the duration of the signal to be transmitted is set to the inter-signal pause time of another station line. (Minimum pause) in some cases, and the signal duration and inter-signal pause must be the same. Satisfies the electrical conditions of the PB signal,
In addition, in order to make the signal duration time and the inter-signal pause time the same time, the switching cycle of PB signal data of the PB signal switch circuits 6a to 6h (the same as the signal duration time and the inter-signal pause time) needs to be 60 mS or more. In the present embodiment, this is set to 100 mS. As a result, the PB signals are allocated to the communication path memory 13 in a correspondence relationship of two types of PB signals for one address, and the two types of PB signals allocated to each address are 100 mS.
Will be alternately switched every time. The memory contents of each address of the communication path control memory 14 are periodically rewritten by the operation of the central processing unit 7 based on the contents of the main memory 8, for example, at intervals of 100 ms in the present embodiment. Next, the transmission operation of the PB signal executed by the above configuration will be described. FIG. 4 is a flowchart of a call connection processing program for explaining the operation of the PB signal transmission method of the private digital electronic exchange according to one embodiment of the present invention, and FIG. 5 is a flowchart of the PB signal transmission program. FIG. 6 is a memory map for explaining the operation of the PB signal transmission method according to the present embodiment.
Is a timing chart of the PB signal transmitted by the PB signal transmission method according to the present embodiment. 4 and 5 are set in a main program of an exchange (not shown). First, when the extension telephone 1 dials, for example, 06-991-1181 as the dialed number of the called party, the dialed number is stored in the memory space allocated to the extension telephone 1 as shown in FIG. "Writing in order from the address. At this time, when the PB signal can be transmitted to the office line, the call connection processing program of FIG.
The transmission request flag SREQ is set to "1" in the main memory 8 (step S01), and the transmission counter SCNT for reading the dial number in the main memory 8 is set to "0" (step S02). As shown in FIG. 6, the transmission counter SCNT functions to sequentially read out the called-side dial digits written in the memory space. That is, an address in the main memory 8 is designated by the count number i of the transmission counter SCNT, and the dialed number contained in the address is read. Since the count number of the transmission counter SCNT is sequentially incremented from "0", the dialed digits are sequentially read from those stored at the "0" address. On the other hand, the PB signal transmission program of FIG.
When the content of the transmission request flag SREQ becomes "1", it is determined in step S2 whether or not the content of the interdigit sign PS is "1". If the content of the interdigit sign PS is "1", the flow proceeds to step S3. . In step 3, the dial contained in the address of the main memory 8 corresponding to the count number of the transmission counter SCNT is read, and the transmission is performed according to the contents of the group counter GCNT that controls the transmission switching to the PB signal group 1 and the PB signal group 2. It is determined whether or not it is the timing when the PB signal of the dial to be supplied is supplied to the multiplexing circuit 11. First, the count of the sending counter is "0".
Therefore, if the dial "0" is read out and the group counter GCNT is "1" and the PB signal group 1 is supplied to the multiplexing circuit 11, the dial "0" corresponds to the dial "0" in step 4. The address number (#S) of the communication path memory 13 of the PB signal switch circuit 6a supplying the PB signal
a) is written to a predetermined address (for example, # 1) in the communication path control memory 14. The predetermined address is an address corresponding to a time slot number on the outgoing highway 16 necessary for transmitting a PB signal to a station line having a transmission request. To such an address (# 1), the address number (#S) of the communication path memory 13 of the PB signal switch circuits 6a to 6h supplying the PB signal corresponding to the dial.
When a) is written, the data DP0 of the PB signal "0" is read out at the time slot t1 on the outgoing highway 16, and sent out to the local line T1 by the operation of the demultiplexing circuit 12. Subsequently, in step S5, "1" is added to the transmission counter SCNT, and the process proceeds to step S6, where the interdigit sign P
S is set to “0”. In the next period of the PB signal transmission program (after 100 mS), if there is a transmission request from the station line T1, the process proceeds from step S1 to step S2 again. Since it is set to "0", the process proceeds to step S7, where the inter-digit sign PS is rewritten to "1". Then, in step S8, there is no signal at the address (# 1) in the communication path control memory 14. .
That is, an address number containing no signal is written.
As a result, a no signal is transmitted to the central office T1 through the demultiplexing circuit 12. Thus, transmission of one PB signal is completed. The required time during this time is 100 ms. In step S3, the dial read from the address of the main memory 8 corresponding to the count number of the transmission counter SCNT is indicated by the contents of the group counter GCNT, and the PB signal of the dial to be transmitted is multiplexed by the multiplexing circuit. If it is not the timing supplied to the channel 11, the process proceeds to step S8, where the address number of the channel memory 13 in which no signal is stored is written in the address (# 1) in the channel control memory 14, and the PB is written to the line T1. The transmission of the signal is delayed for one cycle (100 mS). In step S9, in each cycle of the PB signal transmission program (every 100 ms), all the PB switch circuits 6a to 6h are switched so that the PB signal group 1 and the PB signal group 2 are alternately supplied to the multiplexing circuit 11. At the same time,
In step 10, the content of the group counter GCNT is updated according to the number of the PB signal group supplied to the multiplexing circuit 11. In this way, when the PB signal of the dial to be transmitted is not supplied to the multiplexing circuit 11, the transmission of the PB signal takes one cycle (100 mS).
By delaying, in the cycle of the next PB signal transmission program, it is guaranteed that the timing at which the PB signal of the dial to be transmitted is supplied to the multiplexing circuit 11 is reached. Thereafter, when there is a transmission request from the central office line, steps S1 → S2 → S3 → S4 → S5 → S6 → S again
The process proceeds to the routine of 9 → S10, the next one type of PB signal is transmitted from the station line T1, and then the steps S1 → S2 →
The process proceeds to a routine of S7 → S8 → S9 → S10, and a no signal is transmitted from the same local line. If it is not the timing at which the PB signal of the dial to be transmitted is supplied to the multiplexing circuit 11, steps S1 → S2 → S3 → S8
→ Go to the routine of S9 → S10,
After sending from step 1, step S1 → S2 → S3 → S4 →
Proceed to the routine of S5 → S6 → S9 → S10, and PB
A signal is transmitted from the office line T1, and subsequently, steps S1 → S2
The sequence proceeds to a routine of → S7 → S8 → S9 → S10, and no signal is transmitted from the same line. This is repeated until the transmission of the PB signal corresponding to the dial number is completed for all the dial numbers written in the main memory 8. FIG. 7 is a timing chart of a PB signal transmitted to a station line for which a transmission request has been issued. In the figure, the portion "between digits" is when no signal is transmitted. By the way, when the PB signal is transmitted to one office line as described above, other addresses (for example, # 2, # 3. By executing an appropriate program and writing the address number of the communication path memory 13 containing the PB signal, the PB signal is read out to another time slot on the outgoing highway 16 and the line T2, The PB signal can be transmitted simultaneously from T3. Therefore, PB signals can be sent to many office lines at the same time without having PB sender trunks by the number of office lines. In the above embodiment, the office line is used in a broad concept including a dedicated line. Further, in the present embodiment, the communication path memory 13 is controlled by sequential write / random read. However, when the present invention is implemented, the present invention can be applied to the case of control by random write / sequential read. Further, in the above embodiment, two PB signal generation circuits 5a to 5p are switched by one PB signal switch circuit 6a to 6h, respectively, and 16 types of PB signals are assigned to eight addresses of the communication path memory 13. However, if one PB signal switching circuit 6a to 6h is connected to many PB signal generation circuits 5a to 5p to switch the PB signal, the communication path memory 13 for allocating the PB signal can be further provided. Address can be reduced. For example, when four PB signal generation circuits 5a to 5p are connected to one PB signal switch circuit 6a to 6h and switching is performed, the number of addresses of the communication path memory 13 to which PB signals are assigned is "4". In an extreme example, when it is allowed to increase the interdigit, the PB signal generation circuits 5a to 5p are connected to one of the PB signal switch circuits 6a to 6h, and switching is performed. The number of addresses in the channel memory 13 to which signals are assigned is "1". The maximum digit spacing at this time is 1.6 S in the case of a 100 mS cycle. As described above, the method of transmitting the PB signal in the private digital electronic exchange of the present embodiment is based on the communication path memory 1
A PB signal composed of a plurality of types of PB signal generation circuits 5a to 5p is assigned to one address of the communication line 3, and the data of the communication path memory 13 is stored at a fixed time interval that satisfies the minimum transmission time of each digit of the dial number to be transmitted to the office line. A plurality of types of PB signals assigned to one address are repeatedly and sequentially written in the channel memory 13. When a PB signal transmission request is received, the contents of the channel control memory 14 are rewritten in synchronization with the write interval, and a PB signal corresponding to the called party dial number is stored in the channel memory 13.
At the time of writing to the channel memory 13, the data is immediately read from the channel memory 13 and supplied to a predetermined time slot on the output highway 16, and the PB signal is not written to the channel memory 13. At the time of timing, switching is sequentially performed in synchronization with the write interval,
After delaying the reading until the B signal is written into the channel memory 13, the signal is read from the channel memory 13 and supplied to a predetermined time slot on the output highway 16 to correspond to the called party dialed number. The PB signal is transmitted to the station line for which the transmission is requested. Therefore, PB signal generating circuits 5a to 5p for generating a plurality of types of PB signals per address are assigned to the channel memory 13, and the minimum transmission time of each digit of the dial number transmitted to the office line is satisfied. A plurality of types of PB signals assigned to one address of the channel memory 13 are sequentially written into the channel memory 13 at fixed time intervals, and the contents of the channel control memory 14 are rewritten in synchronization with this interval to rewrite the contents of the channel memory 13. By controlling the communication path memory 1
Only 3 addresses are occupied and P
When trying to send a B signal, many extensions
The PB signal can be transmitted to the office line, etc., no block is generated, the number of simultaneously transmitting office lines of the PB signal is not limited, and the ratio of the address to which the PB signal is allocated to all the addresses of the communication path memory 13 Can be reduced, and as a result, the number of extensions and office lines that can be accommodated as an exchange can be reduced. Therefore, even if the office trunk does not include a PB sender, the number of simultaneously sending office lines for PB signals increases, and the ratio of addresses allocated to PB signals to all addresses in the speech path memory 13 can be reduced. As described above, according to the method of transmitting a PB signal of the private digital electronic exchange of the present invention, a plurality of types of PB signals are assigned to one address in the communication path memory, and A plurality of types of PB signals assigned to one address in the channel memory are sequentially written into the channel memory at fixed time intervals satisfying the minimum transmission time of each digit of the dial number to be transmitted to the channel, and the call is synchronized in synchronization with the writing interval. By rewriting the contents of the channel control memory to control the channel memory, when simultaneously transmitting a PB signal to the office line or the like, only a small number of addresses of the channel memory are used, and a large number of extensions and office lines are used. PB signals can be sent out, etc., no blocks occur, there is no limit on the number of simultaneous sending station lines of PB signals, and PB signals occupying all addresses in the speech path memory are allocated. Thus, it is possible to reduce the number of extensions, office lines, and the like that can be accommodated as exchanges, and to provide an inexpensive in-house digital electronic exchange.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram for explaining a PB signal transmission method of a private digital electronic exchange according to one embodiment of the present invention. FIG. 2 is a detailed configuration diagram of a switch circuit in FIG. 1; FIG. 3 is an explanatory diagram showing data contents of signal data supplied from a PB signal switch circuit to a multiplexing circuit in FIG. 1; FIG. 4 is a flowchart of a call connection processing program for explaining the operation of the PB signal sending method of the private digital electronic exchange according to one embodiment of the present invention. FIG. 5 is a flowchart of a PB signal transmission program for explaining the operation of the PB signal transmission method of the private digital electronic exchange according to one embodiment of the present invention. FIG. 6 is a memory map for explaining the operation of the PB signal transmission method of the private digital electronic exchange according to one embodiment of the present invention. FIG. 7 is a timing chart of a PB signal transmitted by the PB signal transmission method of the private digital electronic exchange according to one embodiment of the present invention. FIG. 8 is a block diagram illustrating a method of transmitting a PB signal in a conventional private digital electronic exchange. FIG. 9 is a block diagram illustrating a PB signal transmission method in another conventional private digital electronic exchange. DESCRIPTION OF SYMBOLS 1 extension telephone 2 extension circuit 3 switch circuit 4 local trunk 5a-5p PB signal generation circuit 6a-6h PB signal switch circuit 7 central processing unit 8 main memory 11 multiplexing circuit 12 demultiplexing circuit 13 speech path Memory 14 Channel control memory 15 Incoming highway 16 Outgoing highway

Claims (1)

(57) [Claims 1] A plurality of types of PB signals are assigned to one address of a speech path memory, and the PB signals are transmitted at fixed time intervals satisfying a minimum transmission time of each digit of a dial number to be transmitted to an office line. writing a plurality of types of PB signals assigned to one address of the speech path memory sequentially speech path memory, the transmission request of the PB signal is generated, the dial number in synchronism with the predetermined time interval
The PB signal written to the channel memory based on the
Address control memory for reading the address
At the timing when the PB signal corresponding to the called party dial number is written in the channel memory, an address for reading the PB signal is immediately read from the channel memory. supplying a predetermined time slot on the highway exit reads, also when the timing of the PB signal is not written in the speech path memory, the following
Wherein after the PB signal obtained by delaying the read to the timing to be written into the speech path memory, and supplied to a predetermined time slot on the highway exit reads from said speech path memory, office line with a transmission request to the PB signal to the A method for transmitting a PB signal of a private digital electronic exchange, comprising: