DE1233917B - Circuit arrangement for switching systems with centralized control of the transmission of switching indicators - Google Patents

Description

Circuit arrangement for switching systems with centralized control of the forwarding of switching indicators There are already switching systems, in particular for telephone purposes, in which information about the operation of switching equipment is stored centrally. Such information relates, among other things, which is of particular interest here, to switching indicators that are to be passed on to other locations, in particular to other exchanges. It is z. B. to number disk impulse series, so-called flicker markers, etc. A single central memory can be provided for the storage of this information, or several memories can be distributed over different points in the switching system. In any case, storage spaces are provided for storing the information; B. are each assigned to the connections with which the viewed information is related.

The invention now relates to such switching systems as above described type, in which the information stored in storage locations by periodic recall of these memory locations can be read. This is the case for switching systems in which the execution of the switching process, steps, such as the establishment and disconnection of connections, such stored information are to be implemented, whereby they change the storage space and also changes themselves are subject. Switching systems based on the time division multiplex principle can also be considered work. Here are e.g. B. so-called circulating memory available, which periodically Provide information relating to the operation of switching equipment.

A circuit arrangement is already known (see German patent specification 970229) in which information read by periodically calling up memory locations is passed on to other exchanges in the form of switching indicators of a certain length by centrally counting the periodic calls to the memory locations concerned. The length of these characters and the length of the associated pauses are determined here. To count the calls, several counting devices are required here, all of which have to count to the end of their switching options. When passing on several different switching indicators, different periods of time must be determined. A correspondingly large number of counting devices must therefore be used here.

However, the invention now shows a way of determining the number of to be used Counting devices can be significantly reduced, thereby also reducing the required circuitry effort is reduced. There will be a few in addition Logic circuits are required, but the effort required for this is comparative small amount.

The invention thus relates to a circuit arrangement for switching systems, in particular for telephone purposes, in which information about the operation of switching devices is stored in a centralized manner and read by periodically calling up the storage locations that store them, and in which the information read is passed on to other exchanges in the form of switching indicators certain time length is carried out with central counting of the periodic calls of the memory locations concerned. This circuit arrangement is characterized in that the counting carried out with the help of a central counting device for specifying time lengths is limited by adding additional coded information about the number of previous calls for repeated calls to the memory locations assigned to the relevant switch indicator which, by evaluating this information, stop the transfer of the relevant switching indicator or zuo, ehöriae pauses when the intended number of calls is reached. On the basis of FIG. FIG. 1 shows the breakdown of a switching system, which can be considered, for example, into the parts which are of interest here; F i g. Figure 2 shows an example of a termination circuit for an outgoing traffic line to which switch flags are to be supplied; F i g. 3 shows in detail the devices of the switching system which cooperate in the counting of periodic calls for information to limit the length of time.

C The outline of the in F i g. 1 C, tT shown switching system briefly explained in order to facilitate understanding of the invention itself. This switching system consists, among other things, of the speech path network K, to which subscriber stations are connected on the one hand, of which the subscriber stations Ta and Tb are shown with their associated subscriber circuits Tsa and Tsb, Z, Z> and to which, on the other hand, terminating circuits for lines are connected, to which the termination circuits A! and Av belong. The traffic between subscriber stations of the switching system shown is routed via terminating circuits such as the terminating circuit Ai. Of particular interest here are the termination circuits to which the termination circuit Av belongs. The traffic leading to other exchanges is routed via such termination circuits. Therefore the line av outgoing from the terminating circuit Av leads to another exchange. When establishing a connection from the subscriber station Ta to a subscriber station that is connected to another exchange, the subscriber station Ta is first switched via the subscriber circuit Tsa and via the voice path network K z. B. connected to the termination circuit Av. The connection is then completed via the line av outgoing from there and leading to the switch in question.

The above-mentioned parts of connection paths leading via the speech network are established here with the aid of the marker M and later separated again. It is in connection with the subscriber circuits Tsa, Tsb ... and with the speech path network K. In addition, it is in connection with the terminating circuits. The line ma leads, among other things, to the terminating circuit Av, via which characters can be delivered there. These include the switching indicators already mentioned, which are to be passed on from the terminating circuit Av via the line av from there. To pass such characters z. B. there brought a relay to respond or to drop out. With the help of a contact, this relay can then transmit signals over the line with outgoing traffic. If the C characters to be passed on are delivered broken down into short pulses, it is advisable to use a relay that can be triggered by short pulses and at the same time has self-switching properties, such as e.g. B. so-called Ferieed relays. Such operating conditions can also be met with the aid of upstream electronic flip-flops.

2 shows an example of a termination circuit for a line with outgoing traffic. The line transformer 2T and the isolating capacitor 2K are located between the line cores 2a and 2b, which are the speech cores here. Further, the through-connect contacts are 2v1 and 2v2 provided as well as the pulse contact 21, are transmitted via the signals to the line when the through-connection contacts 2 v 1 v 2 and 2 are in the working position. The associated relays are called 2 Y C and 21. The occupancy relay 2 U is connected to the line core 2 c , which is used as a test core. The pulse relay 21 can be put into operation by current pulses which are distributed by the marker M, whereby characters in the form of more or less long pulses or series of pulses are passed on via the line. The pulse relay 21 only serves to transfer characters. If audio-frequency signals are to be fed to the line, its contacts must each establish connections to audio-frequency generators.

It is now shown in FIG. 3 explained in detail, in which the aids C required for the temporal limitation of characters etc. are provided. In this fig. 3 a special symbol is used for the memory provided there, which is used to make the representation clear. So the labeled 3 W memory is represented by this icon. It consists of several parts, which are labeled 3 A fV, 3 TW, 3 BW and 3ZW. Part 3BW contains the actual memory locations. Each memory location has a storage capacity of several bits. The part corresponding to a bit is represented by a square. Parts belonging to the same storage space are arranged horizontally next to one another in the figure. A magnetic toroidal core made of iron with an almost rectangular magnetization curve is often used to store information corresponding to one bit. The two magnetic saturation states of such a Rina core are then used as its operating positions.

To query a certain toroidal core on the stored information its address is used in the form of the coordination of its location in the memory. The for All toroidal cores required addresses can be queried with the help of an address generator win, which is labeled 3A1V. It consists e.g. of a ring counting chain Flip-flops that have as many counting positions as addresses are required. With the aid of a code converter connected to it, when an address assigned to a counting position is supplied in a suitable form, so in such a way that the coordination of a Rina core or all of them to one memory location belonging toroidal cores are specified. Since the structure of such an address generator is not the subject of the invention, its presence is merely schematic indicated by a rectangle.

The addresses supplied by the address generator 3AW are initially supplied to the part of the memory 3W labeled 3TW. This part contains the devices required to control the toroidal cores or the storage spaces, which can be constructed in a conventional manner and therefore not here in detail are shown.

Part 3 TW is referred to below as the operating device.

Expediently, all ring cores belonging to a storage location are queried at the same time. The query results are first fed to a buffer memory C C, which is designated by 3ZW and is called a read / write register in the following (r. This device has the buffer parts a, b, c ... z. Each part can contain one of This read-write register is centralized with respect to the ring cores, because it can be used for all storage locations. The storage of query results can also be used to amplify the associated electrical signals be, whereby the Auswertun g is facilitated. As a read-write Reaister may be used by itself loading known flip-flops, which are respectively accommodated by a query result in a certain tilted position. at appropriate places these flip-flops can then suitable for their Auswertuno Signals are tapped off. C C el wires are connected there which lead to other devices statements , e.g. B. lead to logic circuits. There are also other wires connected there, via which signals originating from other memories or logic circuits are fed in, whereby they in turn bring the flip-flops into a certain tilted position. With the help of the operating device 3 TW, the associated information can be transferred to the memory location that has just been called up.

The in F i g. 3 shown parts 3 BW, 3 ZW, 3 TW and 3AW thus together represent a functional information memory according to the above description. Through the connecting wires led to the various parts, such a memory can be inserted into a circuit arrangement, its functions then also being clearly recognizable are. This is also the case in FIG. 3 the case.

In addition to the memory already mentioned, it also has the memory consisting of the memory locations 3BA, the write recorder 3ZA and the operating device 3 TA . Each storage space here has a storage capacity of one bit. The memory locations 3BA represent the terminating circuits to be supplied with characters. As shown in FIG. 2 has already been described in the example shown for a termination circuit, the character can be received by a relay. Now a relay also has a storage capacity of one bit. It is therefore expedient to represent them as storage locations with such storage capacity that belong to the same memory. The lines going out from these memory locations or from these relays are shown in FIG. 3 not shown, however, in order not to disturb the clarity. The write register 3ZA is assigned jointly to the memory locations 3BA.

As already mentioned, the read-write register has 3ZW the serving for the temporary storage of information memory 3 W, the parts a, b, c,. . ., e.g. A character with either the binary value 0 or L can be entered or output for each part. Parts a ... f are used to include the addresses of the body from which information is to be obtained. The information obtained is then divided into parts g. . . 1 recorded. From there they are fed to the evaluation device 3J for evaluation, reshaping, etc., among other things. Resulting evaluation results are fed to the parts m and u ... x. The parts n . . . s are in connection with the counting device 3 L, which is used to count the periodic calls to the same memory location. In part t of the read / write register 3ZW, a special character is entered in the course of the counting. The remaining parts of the read / write register are available for other purposes. In the already mentioned parts u ... x, the addresses of the locations are entered, C where appropriate, to which the relevant information is to be forwarded. These are the memory locations 3BA which belong to the termination circuits of lines. They C are controlled by the operating device 3 TA, the distribution of the information to be supplied being carried out at the same time. Here, here those relays are made to respond and fall to waste that belong to the eligible termination circuits.

In the wiring between the device already mentioned, some logic circuits, namely und gates, blocking gates and mixing gates, are inserted, the function of which is explained in the description of the operation of the entire arrangement. By evaluating the information in the parts ... 1 when calling up a memory location of the memory 3 W, the character to be entered in part m, which indicates the nature of the information to be passed on, and the character to be entered in the parts u ... x Address of the place to which the information is to be passed on. It may be a final circuit for a line with outgoing traffic, as it is for. B. in FIG. 3 is shown. The information to be passed on may e.g. B. be a so-called flicker termination sign, which is to be applied to one of the two speech lines. This final flicker consists of consecutive characters, each 150 milliseconds long and between which there is a pause of 475 milliseconds.

The memory locations are now called up periodically at fixed intervals using the addresses supplied by the address generator 3AW. This also includes that memory cell into which the aforementioned evaluation result was previously entered via the read-write register 3ZW. With these calls that are now made, the flicker termination character is to be delivered at the point which is indicated by the address that is to be found in parts u ... x of the read / write register 3ZW. This delivery takes place in repetition " until there is a special sign of the termination of the delivery.

Now the time interval with which the relevant memory location is periodically called has nothing to do with the length of the characters and the length of the pause associated with the flicker termination character to be supplied. These time lengths can, however, be obtained by counting the periodic calls to the relevant memory location. The counter 3L and the logic circuits 3 K 1, 3 K 2, 3 G, 3 M 1 and 3 M 2 are used for this purpose.

The periodic calling of the same memory locations takes place in this memory z. B. with a time interval of 17 milliseconds. If for the first time the address of the controlled location is present in parts it ... x and the character for the delivery of the flak final character is present in part m of the read / write register 3ZW, the delivery of the flicker final character begins. For this purpose, the relevant terminating circuit is controlled by the operating device 3 TA with the aid of the address. In addition, a signal is sent from part m of the read-write register 3ZW via the unlocked locking gate 3 G to the terminating circuit in question, which signal there triggers the delivery of a character.

The point in time at which the blocking gate 3 G will be blocked will still be specified. From part ni, the counter 3 L is also started, which counts the calls now made to the same memory location. In the present call, the number 1 is accordingly entered in a specific code in parts n ... s of the read-write register and from there in the memory location called up.

The next time this memory location is called up, the same terminating circuit is activated again as before and a signal is again sent there via the blocking gate 3 G , by means of which the previous delivery of the character is continued until the next activation. This achieves a character length of 34 milliseconds. In addition, the number 1 previously entered into the accessed memory cell is changed to the number 2 with the aid of the counter 3L. It may here z. B. Code characters can be used after the binary code. In a corresponding manner, the relevant memory location is called up several times, the delivery of the character being extended by 17 milliseconds and the number stored being increased by the number 1 . When the number 9 is reached, the character to be delivered has the prescribed length. The AND gate 3 K 1 is now connected with its two inputs to the two parts of the read / write register 3ZW which have to receive binary code character elements with the place values 20 = 1 and 23 = 8 . After the counting device 3 L has counted to 9, the next time the memory location have the herein Binärkodezeichenelemente L. the binary value This has the consequence that supplied by the output of the AND gate 3K1 a signal for notifying the end of the character ID is C, the the blocking of the blocking gate 3 G causes it to reach its blocking input via the mixing gate 3M2. This signal also passes through the mixer 3 M 1 to part t of the read-write reffister 3ZW and is entered there as a symbol for the further blocking of the blocking gate 3 G , so that it can also be used later in the subsequent calls to the relevant memory location from here to the blocking input of the blocking gate 3 G, also via the mixing gate 3M2. After the number 9 has been counted, there is no further extension of the character supplied by the terminating circuit in the subsequent calls. However, the counter 3L continues to count with each further call.

When the number 37 is reached, the pause until the next character has reached the prescribed length. The AND gate 3 K 2 is connected with its three inputs to the connecting wires between the counting device 3 L and the parts n ... s of the read / write register 3ZW which are used in the counting and which originate from the parts , which have to include binary code character elements with the place values 20 = 1, 22 = 3 and 25 = 32 . If the counter 3L had counted to 37 , these three binary code character elements supplied by it have the binary value L. This has the consequence that the output of the AND gate 3 K 2 supplies a signal to the counter 3 L which represents the end of the Pause reports and causes the number 1 to be entered again into the read-write register 3 ZW instead of the next higher number. In addition, this signal is also supplied to part t of the read-write register 3ZW via the mixer 3M1, whereby the character previously entered there for the blocking of the blocking gate 3 G is changed so that the blocking gate 3 G is no longer blocked. This restores the state that prevailed at the beginning of the first character supplied. When the relevant memory location is called up, a character is sent to the terminating circuit in the same way as before, which is then followed by the associated pause. This is repeated again afterwards, etc.

Is obtained on the basis of the information with the aid of in parts a ... f of the read-write register 3 ZW respectively standing address to be obtained in that the supply of the Flackerschlußzeichens be discontinued, it is obtained by the evaluation device in the 3J Part m each character coming to stand changed, whereupon the blocking gate 3 G and the counter 3 L no longer receive a signal. After that, no more signals are sent to the terminating circuit in question. The delivery of the flicker termination sign is thus canceled.

It should be noted that the terminating circuit in question can also be supplied by signals in a manner other than that described above. So z. B. a special switch-off signal for the relay to be controlled can also be supplied at the beginning of the pause between the characters. For this purpose, the AND gate 3 K3 is provided, which emits a signal when it is supplied with a signal from part t of the read / write register 3 ZW and from the AND gate 3 K 1 . This happens for the first time when the counter has counted 3L to 9 .

It should also be noted that the counting of the periodic calls can also be carried out in a way other than that described above. Essentially, there was counted up to a fixed number by adding up the successive calls to the same memory location. Instead, the specified number of calls can be entered in the form of a code character for the relevant memory location and a subtraction can then be made with each call using a suitable counter until the number 0 results. In this way, too, the lengths of characters and the pauses required can be limited.

In the example described above, the information about the calls is stored in coded form in memory locations. They are also processed in this form by the counting device. A binary code was used as the code, the code characters having six digits. These are code characters of the form 6 X 1 of 2. Instead, code characters of other forms can also be used, e.g. B. Form 2 X 2 of 5. It is convenient to weils JE such a code to use that code symbols take as little capacity to complete and that the notification of the termination of marks and spaces can be done with the simplest possible tools. In the example described, only one AND gate is required for this in each case. These are the AND gates 3 K 1 and 3 K 2.

In the example described above for the forwarding of characters of a certain length, a special character was written in the relevant memory location via the part m of the read / write register 3ZW, by means of which the counting with the help of the counter 3 L and the in Activity occurring associated linkage circuits is initiated. This special character, in cooperation with the mentioned logic circuits, determines the nature of the character to be passed on and thus ultimately the number of calls to be made. This number is here directly determined by the way in which the logic circuits 3 K 1 and 3K2 are inserted into the circuit. The number of calls that have already been made is supplied to them, whereupon they may supply a signal that reports the time limit of the character or the pause. It should be noted that the number of taking place Views can also be affected by a particular method of counting the counting device 3 L. In FIG. 3 , only those link circuits are provided that are required for the delivery of the flicker termination signal. However, further logic circuits can also be provided, with the help of which other characters, e.g. B. dial pulse series are supplied. The logic circuits to be used for this are then to be inserted into the arrangement in a correspondingly different manner.

In order to determine in this case the peculiarity of the character to be passed on or the calls to be made in each case, information about other parts of this read-write register must then be written to the relevant memory location in addition to the part in the read-write register 3 ZW will. The character of the character can then be specified later when calling up memory locations, from which it can be determined which logic circuits are to be used for the transfer. Under certain circumstances it can also be useful to switch the counting device in order to achieve a special counting method. Instead of how it is z. B. at the in F i g. 3 or shown arrangement is seen before 'to let counting during the pause following a character, it can also be useful to start counting again at the beginning of a pause with the counting.

Instead of letting the time limits for counting be determined by the way in which the logic circuits are inserted into the arrangement, this can also be done by counting the number of calls to be made directly in the form of a binary code character or another code character at the relevant memory location is enrolled. There are then different procedures. Either, as already mentioned, this binary code character is then converted into the code character corresponding to the number 0 with the aid of a counting device subtracted each time it is called, whereby the counting is ended in each case. Or the calls that take place are special, namely as in the arrangement according to FIG. 3, counted and each time a comparison of the code characters indicating the numbers present is carried out until the numbers are equal, whereby the calling and counting is ended. The same logic circuits can then be used for the different characters to be passed on. In other words, because the number of calls to be made is entered numerically in the corresponding memory locations for the different types of characters that occur, it is achieved that the same logic circuits can report the time limits for different types of characters.

Unless the period of calling memory locations through here conditions not specified for the function of the arrangement are specified in advance is, they will expediently be chosen so that the required length of time result from as few and integral multiples of this period as possible.

In cases where the memory locations have to be called up more frequently than is actually necessary for the purposes of counting to limit the time of characters and pauses, savings can be achieved through additional measures. The greater the number of calls to be counted, the more memory capacity is required for the memory locations. The effort for the counting device is also greater. This effort can be reduced if, instead of each call, only a certain part of the calls of the numbers is taken into account and the calls that actually have to be taken into account are counted separately from the calls that have taken place with the help of a precounter. So it is to use a countdown that z. B. only with every fifth call forwards signals to the counter 3 L, which they put into action. The numbers to be processed by the counter in this case and the numbers to be stored are five times lower than otherwise Calls for counting is taken into account. In this case, it is advantageous to combine the memory locations, which each provide information to be limited by counting their calls of the same length, into groups and to count a different particularly suitable part of calls separately for each group of memory locations. In this case, too, a common pre-counter can be used for all memory locations and thus also for the various groups of memory locations. Information is then to be stored with the aid of an additional memory space provided for each group, which information indicates when memory locations of a group are called up when a call to be taken into account is encountered when counting calls. For this purpose z. For example, information is kept on the additional storage space of a group about how many calls are to be counted in total and how many have already taken place before the counting device 3L has to come into action.

Claims (2)

1. A Schaltungsanordnun g for switching systems, in particular for Femsprechzwecke in which information is stored centralized on the operation of switching devices and by periodically calls which they are read establishment holding memory locations and in which the transfer of read information specific to other switches in the form of switching signals chronological Länae takes place with central counting of the periodic calls of the relevant memory locations, characterized in that the counting carried out with the help of a central counting device (M) for the purpose of specifying time lengths is limited by the fact that the memory locations (3BW) assigned to the relevant switching identifier Additionally, information written in coded form about the number of previous calls when calling up logic circuits (3K1, 3K2) is supplied, which by evaluating this information at Er If the intended number of calls is sufficient, the transfer of the relevant switching indicator or associated pauses will end. 2. A circuit arrangement according to claim 1, characterized in that when memory locations (3 BW) are called up there and read information about the number of calls is supplied to the central counter (3L) and written there again after correction with regard to the call currently taking place. 3. Circuit arrangement according to claim 2, characterized in that the number of calls to be made are entered numerically for the various types of characters occurring in the relevant memory locations (3BW), so that the same logic circuits report the time limits for different types of characters. 4. Circuit arrangement according to one of the preceding claims, characterized in that the memory locations (3BtV) are called with a period such that the required time lengths are as few as possible and CCC are only integer multiples of this period. 5. Circuit arrangement according to one of claims 2 to 4, characterized in that instead of each call, only a certain part of the calls is taken into account for counting and that the calls really to be taken into account are counted separately from the calls taking place with the help of a precounter. 6. A circuit arrangement according to claim 4, characterized in that the memory locations, which each provide information to be limited by counting their calls of the same length, are combined into groups and that another particularly suitable part of disturbances is counted separately for each group of memory locations. 7. A circuit arrangement according to spoke 5, characterized in that a "common Cr pre-counter is provided for all groups and that information is stored with the aid of an additional memory space provided for each group, which indicates when the memory locations of a group are called up when each counting of calls, a call to be taken into account is encountered .