KR100208250B1 - Method for assigning the slots to each devices in a switching system - Google Patents

Abstract

According to the present invention, in the PCM communication between the lower processor 10 and the device of the electronic switchboard, the state of the channel connected to the device line is followed by the process according to the present invention, thereby recognizing the device channel mounted and detached by itself. The present invention relates to a method for allocating time slots for PCM communication in an exchange that provides convenience in cold operation. The above time slots are hardware-configured to allocate desired time slots through negotiation with each device. It is possible for a device to selectively have a desired time slot for the device from two time slots up to 32 time slots that the channel distributor can have, and also by using the method according to the invention, in the lower processor 10 itself Recognizes the device so that the device can be programmed individually during mounting and dismounting There's no need to squeeze ram into new ones, and you don't have to bring down your system, which can save you a lot of trouble.

Description

How to Allocate a Time Slot from a Switch to a Device

1 is a block diagram illustrating a time slot allocation method of PCM communication in an exchange according to the present invention, and is a block diagram of a hardware system to which PCM communication is applied.

2 is a flowchart of a process in which a lower processor allocates a desired time slot while negotiating with each device according to a preferred embodiment of the present invention.

3 is a flowchart of a process of dynamically allocating channels when a device is added during normal operation according to a preferred embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

10: processor 20, 22, 24, 26: first, second, third, fourth channel distribution unit

The present invention relates to a method of allocating time slots in pulse code modulation (PCM) communication between a processor and a device in an exchange. In particular, the present invention actively matches devices requiring different time slots in an electronic switch. A method of allocating time slots is provided.

A method of allocating time slots in an all-electronic exchange such as a conventional TDX-100A is as follows.

First, the communication between the processor and the device uses the TD-bus, and the device is determined according to which block the processor belongs to, and the program initialized initially by recognizing the path to communicate with the device is not changed. Each occurrence must be reprogrammed.

In other words, programs initialized by hand by the programmer first recognize only as many devices as input devices and continuously check the number of devices until the command is changed again to run the power and do not allocate the channel efficiently. There was no quick check.

In addition, since the lower processor does not recognize itself every time the device program is mounted and dismounted, there is a disadvantage that the programmer must program the device changes.

Accordingly, the present invention has been made to solve the above-mentioned drawbacks of the prior art, and the PCM communication of the exchange is to communicate with the lower processor in a certain time slot for each device through negotiation with each device at the time of initialization. The purpose of the present invention is to provide a time slot allocation method for PCM communication that can be initialized by the lower processor.

In order to achieve the above object, the present invention provides a method for allocating time slots to a plurality of devices connected to each channel through a predetermined number of channels in an electronic switch, comprising: selecting one channel; Step 1; Transmitting a negotiation message inquiring whether to use a time slot to a device connected to the selected channel; Determining whether there is a request for a time slot from the device in response to the negotiation message, and allocating the requested time slot from the device; A fourth step of adding the number of the selected channel to the value obtained by dividing the time slot requested by the device by 2 and updating the resulting value to the selected channel until the preset channel reaches the predetermined number of channels; Provided is a time slot allocation method from a switch to a device comprising a fifth step of repeating the first to fourth steps.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a schematic block diagram of an exchange suitable for applying a time slot allocation method using PCM communication in an exchange according to the present invention.

In FIG. 1, the electro-electronic switch includes a lower processor 10, four channel distributors 20, 22, 24 and 26, and sixteen devices connected to each channel distributor.

In general, the lower processor 10 controls the general communication device, and controls the information with the general communication device. In addition, the lower processor 10 loads the firmware for performing the time slot allocation process according to the present invention and allocates the time slot of the device by recognizing device changes when mounting and dismounting the device.

In addition, the lower processor 10 may be connected to the first, second, third, and fourth channel distribution units 20, 22, 24, and 26 to accommodate a maximum of 64 devices of 16 units each.

The first, second, third, and fourth channel distribution units 20, 22, 24, and 26 receive information from the lower processor 10 through the respective PCM links according to the information received from the lower processor 10. It also distributes data with 32 slots of 2,048Mbps into data having two time slots of 128Kbps to fit the general device and distributes them to communication devices through each channel. (10) via PCM link.

Hereinafter, a flowchart of a process of allocating a desired time slot while negotiating with each device by controlling a channel distribution unit by a lower processor will be described in detail with reference to FIG. 2.

First, a process of initializing a channel of PCM communication between the lower processor 10 and the device. Basically, the lower processor 10 and each of the mounted devices are negotiated with each other until the desired time slot is allocated through negotiation. It must be hardware configured to communicate.

This is because a regular telephony device uses two time slots and initializes to two time slots, which are the minimum units required for communication, although the device may optionally have up to 32 time slots that a maximum specific channel distributor can have.

The time slot allocation method according to the present invention begins with step 30 of selecting a channel. In this step, the processor 10 assigns 1 to a variable Q called channel number, which is used to define the position of 64 channels arranged in sequence or the number assigned thereto. Thus, a first channel corresponding to variable 1 is selected and ready to negotiate with a device connected to that channel.

The processor 10 then sends a message to the device via the selected first channel to each device connected to the selected channel a negotiation message to find out how to use its identification number and how many time slots (step 32). .

After transmitting the negotiation message, it is determined whether a response is received from the corresponding device receiving the message (step 34).

If no response is received from the device, 1 is added to the number of repetitions (step 38) and the operation is repeated from step 32.

In this step, it is repeated from the step of repeatedly sending a message to the device in order to prevent an error. If the number of repetitions is too large, a waste of time is generated, and if there are too many loops, an error may occur. The number of repetitions is only repeated for a predetermined number of times, for example five times.

However, if a response is received from the device during the process of determining whether a response is received from the corresponding device that sent the message (step 34), the process proceeds directly to step 40.

In step 40, if there is a response from the device, it is determined whether there are a number of time slot requests from the device (step 40).

If there is no request of the time slot responded in this step, increase the channel number variable (Q) by 1 (step 42) and then transmit the above-described negotiation message to the device connected thereto through the communication channel in the next step (step Repeat from 32).

On the other hand, in step 40, if there is a response time slot, the time slot is allocated to the corresponding device by the time slot requested to the corresponding device (step 44).

Next, in step 46, a new channel number Q is allocated according to the following equation according to the number R of allocated time slots.

In this equation, the variable R is the number of time slots (R) requested by the device. That is, since two time slots are allocated to one channel by hardware initialization, the channel number (Q) is added to the numerical value resulting from dividing the number of time slots (R) requested by the device by the number 2. Allocating a time slot to the device from the channel corresponding to the value is performed (step 46).

For example, suppose that the current channel number is selected as 5, and a device connected to this channel 5 requires 10 tie slots, according to the above-described formula, (10/2) + 5 = 10, that is, a new channel number. Will start at 10.

However, when the processor 10 recognizes this, it is one channel of channel 5, and it is not recognized as five channels.

At this time, the physical channels having the numbers 6, 7, 8, and 9 and the devices connected to the channels are not considered to be present, which is regarded as one channel of channel 5.

Therefore, the next negotiation is negotiated with channel 10, and the same procedure is followed by the processor to recognize the slot required by the device and assign a time slot.

In step 48, if the selected channel number is the preset number of channels, that is, the channel number is 64 or less, the message is repeatedly transmitted to the device connected thereto through the selected communication channel (step 32) through the above-described equation (step 48). If the channel number is greater than 64, it is determined that there are no more channels to negotiate (step 48).

In the above-described time slot allocation process, a device may be detached and revived, or a device may be newly mounted due to an increase in the device.

According to the present invention, when a new device is mounted, a time slot allocation can be requested from a newly mounted device by requesting an interrupt to the processor 10, which will be described in detail with reference to FIG. 3.

When an interrupt is generated, the processor 10 recognizes the device that generated the interrupt and prepares to negotiate with the device corresponding to the corresponding channel number where the interrupt was generated (step 60).

Then, a message is transmitted to a device channel having two time slots to find out the device number and how many time slots to write to each device corresponding to the channel number (step 62).

Then, after initialization to the processor 10 (step 62), it is determined whether there is a response from the corresponding device that sent the message (step 64), and if it is determined that the response is a response time to determine how many time slots are requested. Go to step 70 of checking the slot, if there is no response, go back to the step of turning the loop a certain number of times (step 66) and check for a preset number of times whether or not a response is received.

If there is no response as a result of the determination, in order to prevent an error, the message is repeatedly transmitted for a predetermined number of times from the step of repeatedly transmitting a message to the device (step 66).

On the other hand, if the response does not come from the device, 1 is added to the number of repetitions (step 68) and the process is repeated from step 62.

If the number of repetitions has been reached to such a device as five times as a preset number of times, the process proceeds to step 70.

Also, if a response is received from the device during this process, proceed to step 70.

Next, if there is a response from the device in this step, it is determined whether there is a time slot allocation request from the device (step 70).

On the other hand, in step 70, when there is a response time slot, the time slot is allocated to the corresponding device by the number of time slots requested to the corresponding device (step 72).

As described above, it is determined whether there is a time slot that has been responded (step 70), and if there is no response even if the response time slot has been repeated a predetermined number of times, the communication channel is recognized as bad and reported to the main processor ( Step 74).

Then, the lower processor 10, which determines that the device line is defective, regards the device line as a failure and does not connect the time slot.

As described above, the present invention has the following effects.

First, the communication channel between the processor 10 and each of the devices can be actively changed without being fixed, and the lower processor 10 may be initialized from the position of the lower processor 10 even if the characteristics of the block determined at the beginning of the system are changed. There is no need to reprogram through the hands of the programmer.

Secondly, due to newly mounted and detached devices, the time slot for PCM communication in the exchange is allocated by recognizing the mounted and detached devices by themselves according to the present invention without having to download the electronic switch to rewrite the program. do.

Claims (6)

Claims [1] A method for allocating time slots to a plurality of devices connected to each channel through a predetermined number of channels in an electronic switch, comprising: a first step of selecting one channel; Transmitting a negotiation message inquiring whether to use a time slot to a device connected to the selected channel; Determining whether there is a request for a time slot from the device in response to the negotiation message, and allocating the requested time slot from the device; A fourth step of adding a number of the selected channel to a value obtained by dividing a time slot requested by the device by two and updating a resultant value to the selected channel; And a fifth step of repeating the first to fourth steps until the selected channel reaches the preset number of channels. The method of claim 1, wherein the step (3) includes assigning a next rank channel to the selected channel if there is no request for a time slot from the device. The method of claim 1, wherein the time slot allocation method further comprises: determining that a device of the electronic switchboard is newly mounted, and allocating a time slot to the newly mounted device. Assignment method. 4. The method of claim 3, further comprising: a first step of transmitting a negotiation message for inquiring whether to use a time slot to the newly mounted device; And determining a time slot request from the newly mounted device, and allocating as many time slots as the requested number of time slots to the newly mounted device. 5. The method of claim 4, wherein the second judging step includes retransmitting the negotiation message repeatedly for a predetermined number of times, if no response is received from the newly mounted device. How to allocate time slots. 5. The exchange of claim 4, wherein the third step determines whether there is a response time slot, and if there is no response in the response request, determines whether to recognize the communication channel as bad and report to the lower processor. How to allocate time slots to devices.