JPS60124142A - Time division multiplex communication system - Google Patents

Abstract

PURPOSE:To improve the communication efficiency of the whole system by changing a table for the number of time slots to be assigned to respective circuits of a time division multiplex communication circuit and its order in accordance with transmission results within a past prescribed time. CONSTITUTION:A setter 6 regulates the number A of time slots (TSs) of a table 7, namely the length of a table 9, the length B of an unrewritten fixing part, the length C to be changed in accordance with transmission status, and the frequency (communication interval) rewriting the length C. A table 8 forms data to be stored in a variable part in the table 9. The table 9 controls the assigning order of the TSs and the number of TSs assigned to respective communication control parts 2-5 on the basis of addresses. A register 10 stores the addresses of the table 9 and a register 11 counts up the number of times of transmission after the change of the contents of the variable part in the table 9. A synchronizing device 12 selects a communication control part to which the current TS is to be assigned from the table 9 and sends a synchronizing signal to the communication control part. Thus, the TSs are applied in accordance with the number of times of transmission and the communication efficiency is improved.

Description

Detailed Description of the Invention (Field of Application of the Invention) The present invention connects a synchronous control device and a number of communication control devices to a common communication network, and converts fixed length data consisting of the first few bits into one packet. , a time division multiplex communication device that transmits and receives data between the communication control devices using one time slot as a fixed time during which one packet can be transmitted,
In particular, the transmission amount of the system as a whole is improved by changing and controlling the allocation order and number of time slots (frequency) within one period according to the number of transmissions within the past scheduled time of each communication control device. The present invention relates to a time division multiplex communication device.

(Background of the Invention) FIG. 1 is a block diagram showing an example of a conventional time division multiplex communication device. The synchronous control device 1 includes a synchronous signal transmitter 12 and a distributor 16. The synchronization signal transmitter 12 is
Communication control devices 2, 3, 4.

The distributor is also connected to the communication control device [2, 5, 4. It is connected to each of 5.

The synchronization signal transmitter 12 transmits a synchronization signal indicating which of the communication control devices 2 to 5 the time slot is allocated to. As a result, only the assigned communication control device, if there is transmission data, transmits one packet of data.

The distributor 16 transfers the transmission data from the communication control device to the communication control devices 2, 3, 4.5.

FIG. 2 shows time slot allocation and communication control i-devices 2, 3, 4. This shows the operation of No. 5. In the figure, °C and T2 to T5 are respectively communication control device 2 to
5, and R2-R5 indicate the reception timings of communication control devices 2 to 5, respectively.

As is clear from the figure, time slots 1 and 2.

3 and 4 are communication control devices 2, 3, 4, respectively. 5
is assigned to. That is, for example, in time slot 1, only the assigned communication control device 1 transmits, and the communication control device 2.1 transmits data via the 1 distributor 16. 6.
4. Each one is received at 5.

In addition, in time slot 2, only the assigned communication control device 6 transmits data, and the 1 distributor 16 transmits data to the communication control device 2. 6. 4. 5 to be received at. Similarly, in time slot 6 and time slot 4, only the communication control device t4 or 5 to which one is assigned can transmit, and the distributor 13 transmits the communication control device ff1f2.
．． 3. 4. 6. Sent a scent note to be received.

In such a conventional allocation method, if one period is the time during which the time slot allocation order is changed, if at least one of the communication control devices in the group does not transmit,
Until the communication control device tffi starts transmitting again,
-There is a drawback that the amount of transmission per cycle decreases.

The time chart in FIG. 6 shows an example of the amount of transmission per period. In this example, timeslot 1 is assigned to communication control device 2, and subsequent timeslots) 2. 3. 4 is assigned to communication control devices 3, 4.5, respectively. And time slot M, 2,
3.4 constitutes one cycle.

In the first cycle, there is a transmission from the communication control device 2 in time slot 1, and in time slot 2, there is a transmission from the communication control device 6.
In time slot 6, communication control device 4 also transmits, and in time slot 4, communication control device 5 performs transmission, respectively.

Further, from the second period onward, only two communication control devices perform transmission in time slot 1, and in the remaining time slots 2 to 4, no communication control device performs transmission.

Therefore, if the transmission amount in the first period is 100%, -
During the period, communication controller 2 in time slot 1
From the second cycle onward, in which only transmits data, the amount of transmission during -cycles decreases to 25N. The lower graph in Figure 6 shows this.

Another example of the conventional time division multiplex communication system is
As shown in Japanese Patent No. 0-92015, there is a method in which a synchronization control device receives a transmission request from a communication control device and allocates a time slot only to the communication control device that has made the transmission request.

FIG. 14 shows an example of the configuration of JP-A-50-92016.

The synchronization control device 1 includes a transmission request receiver 35, a synchronization signal transmitter 12 connected to the transmission request receiver 35, and a distributor 1.
6. Transmission request receiver 65. The synchronizing signal transmitter 122 and the distributor 16 are connected to the communication control device 2 through separate signal lines. 3. 4. It is connected to 5°C.

The transmission request receiver 65 receives the transmission request from the communication control device 2, 3゜4.5, and transmits the result to the synchronization signal transmitter 12.
send to The synchronization signal transmitter 12 transmits f! according to the reception result of the transmission request receiver 65. Allocate time slots only to the communication control device that has requested it.

However, in the method of JP-A-50-92016, in order to transmit and receive transmission requests, the configurations of the synchronous control device and the communication control device become complicated. Both the device and the communication control device require extra overhead, which has the disadvantage of reducing transmission efficiency and transmission speed.

(Object of the Invention) The present invention has been made in order to eliminate the above-mentioned drawbacks, and its purpose is to prevent past transmissions from each communication control device without using transmission requests from each communication control device. Provides a variable time division multiplexing communication device that can increase the amount of transmission (or transmission efficiency) by changing the order and number (or frequency) of time slots assigned to each communication control device according to the number of times. There is something to do.

(Summary of the Invention) The present invention provides a means for improving the amount of transmission per unit time, which decreases when a communication control device that does not send or receive an i-request occurs.
−The allocation order and number of time slots within the period (
By preparing a table for managing the number of timeslots and changing a part of the table according to the number of transmissions by each communication control device within the past scheduled time, the l1kt order and number of time slots to be assigned to each communication control device can be determined. It is distinctive in that it has been changed.

(Example of the invention) FIG. 4 shows a block diagram of an embodiment of the present invention.

In this figure, the same reference numerals as in FIG. 1 represent the same or equivalent parts.

As is clear from this figure, the setting device 6 is connected to the first table 7.
, second daple8. Third table 9. Second register 11
．． and the second register 11. Further, the synchronization signal transmitter 12 is connected to the first Lujistar 10. 1st table 7,
Sixth table 91 and each communication control device 2~
Connected to 5.

The distributor 16 connects the communication control devices 2 to 5. and microprocessor 14, while microprocessor 14
1st table 7, 2nd table.

8. Third table 9. Runstar 10. Second register 11. and is connected to the distributor 16.

The first table 7 has - the number of time slots in the period A - that is, the length of the sixth table 9 is, in this example,
A=8), in the sixth table 9, the length B of the fixed part used without rewriting (in this example, B=4),
In the third table 9, the length C of the variable part (C=4 in this example), which is placed at the rear of the fixed part and whose contents are rewritten according to the feed state, and the sixth table 9 The frequency of rewriting the contents of the variable part of the variable section, that is, the interval D of the number of transmissions (in this example, D=4) is defined. Each of the above numerical values A to D is set by the setting device 6.

The second table 8 is a work area for creating data to be stored in the variable section of the third table 9. This data is set by the setting device 6, for example, initial value 1,
2,5.4 are set.

The third table 9 manages the time slot allocation order and the number of each time slot allocated to each communication control device by having addresses of the communication devices R2 to R5. This fifth table 9 has a fixed length B (B=4) defined in the first table 7.
) and a variable length C (C==4), that is, a total of (A+B) (8 in this example) time slot designation areas.

In this example, the setter 6 sets the fixed part to [1, 2, 3,, 11] and the variable part to [: 1, 2...] as the initial values of the third table 9. ．． 5.4:].

The second register 11 stores the address (0 to 7) of the fifth table 9 corresponding to the current time slot, and is set to an initial value of 0 by the setter 6, for example.

The second register RO counts the number of transmissions that have occurred after the contents of the variable section of the fifth table 9 have been once rewritten, and is set to an initial value of 0, for example, by the setter 61C.

The synchronization signal transmitter 12 transmits the second register according to the flowchart shown in FIG. 5, as will be described in detail later.

The address of the communication control device to which the current time slot is to be assigned is extracted from the address in the third table 9 indicated by , and a synchronization signal is transmitted to the communication control device indicated by the address.

Here, each step of the flowchart shown in FIG. 5 will be explained.

Step 851: Add Ml to the current value of the first register 10.

Step 852...The new content (value) of the first register 10 is set to the value A defined in the first table 7 (the number of time slots in one period, that is, in this example,
8) is exceeded, and if it is exceeded, proceed to step 8.
The process advances to step 55, and if the value has not been exceeded, jumps to step 854.

Step 853...The new contents of the register 10 are not forced back to °1'. Therefore, the first Rujistha
The content of 0 changes from 1 to 1 in this example as the number of transmissions increases.
8.1 to 8 are repeated.

Step 854...The content of the address in the third table 9 that is equal to the value (content) of the register 10 is retrieved.

Step S55: A synchronizing signal is sent to the communication control device according to the content extracted in the previous step 854, and a time slot for signal sending is assigned.

If the received synchronization signal is one that allocates a time slot to itself, the communication control devices 2 to 5 transmit one packet of data in that time slot. Data transmitted from the communication control devices 2 to 5 is transmitted to the four communication control devices 2 to 5 and the microprocessor 14 via the distributor 13.

The microprocessor 14 operates as follows according to the flowchart shown in FIG.

First, when there is output data from the distributor 16, the transmission is detected (step S61 in FIG. 6).
Using the stored value as an address, the communication control device 2 to which the current time slot is assigned is transferred to the third data table 9.
5 (step 562 in FIG. 6).

Next, after moving the contents of the second daple 8 forward one by one, the address retrieved in the previous step is written at the end (fourth in this example) (step 563 in Figure 6).
. ``11'' is added to the second register 11 (step 564).

Then, it is determined whether the updated value of the second register 11 exceeds the reference number of transmissions (frequency) for variable part rewriting in the sixth table 9, which is specified in the first table 7 (see FIG. 6). step 565).

If the determination in step S65 is not satisfied, the process in FIG. 6 ends. On the other hand, when the above judgment holds true,
Transfer the contents of the second table 8 to the sixth table 9, and
The variable part data in table 9 is updated with the contents of second table 8 (step S66 in FIG. 6). After that, the value of the second register 11 is set as IOw.

Next, in this example, as mentioned above, A=8.
Set B=C=D=4, and further set communication control devices 6 to 4.
The operation of FIG. 4, especially the changes in the contents of each table and register, and the operation of the microprocessor 14, assuming that the communication controller 2 does not transmit and only the communication control device 2 transmits continuously, will be described below. This will be explained with reference to Table 1.

Note that, as mentioned earlier, the contents of the second table 8 and the third table 9 are set by the setting device 6 to be (1,
2,3,4), [1,2,5,4゜1.2,3,4:]
It is assumed that the initial values of the first register 10 and the second register 11 are both "OI".

First of all, as shown in Table 1, the Lujistar 10 is:
Table 901 containing addresses of communication control device 2
Indicates how to speak. Therefore, by the synchronization signal transmitter 12,
A time slot is assigned to the communication control device 2, and the communication control device 2 performs the first transmission.

Table 1 On the other hand, the second register 11 becomes +11, indicating that one transmission has occurred. Also, as shown in Table 1, the contents of the second table 8 are moved forward by 1@, and Ml, which is the address of the communication control device 2 that just sent the message, is stored in the fourth word that is blank. be done.

The contents of the register 10 are updated one after another in the order of 12'-+131→14+, and time slots are assigned to the communication control devices 2-4. However, since these transmission control devices do not perform transmission, the second register 1
The value of 1 does not change.

When the value of the register 10 reaches 151, the second transmission from the communication control device 2 is performed again.

At that time, as shown in Table 1, the content of the first register 10 is 151, which corresponds to the fifth word containing the address 11' of the communication control device 2 in the third table 9.
On the other hand, the second register 11 indicates the number of transmissions 121 performed so far.

The contents of the second table 8 are further shifted forward by IffFj, and 111, which is the address of the communication control device 2, is stored at the fourth word, which is 9 white.

Continuing ℃, the contents of the 10th Lujista are 16" → 17'
−+181 and are updated one after another, and the communication control device 2~
4, time slot allocation is performed. However, as described above, since these transmission control devices do not perform transmission, the value of the second register 11 does not change.

When the value of the register 10 becomes 11'' again, the communication control device 2 also performs the sixth transmission.

At this time, as shown in Table 1, the content of the second register 11 is 16', and the content of the second table 8 is [4,1
, 1, 1].

Similarly, when the communication control device 2 performs the fourth transmission, the contents of the second register 11 once become 14 + and then cleared to '0'', as shown in Table 1. On the other hand, the contents of the second table 8 are [1, 1, 1, 1]
becomes.

As described above, since the transmission was performed four times, the contents of the variable part of the third tape node 9 are changed to the contents [1,
1, 1, 1), all four words of the variable part are 11
'.

Therefore, from then on, as is clear from Table 1,
All time slots in the variable section of the sixth table 9 are allocated to the communication control device 2.

The time chart (A) in FIG. 7 shows the above-mentioned transmission state according to the present invention. In addition, (B) in the same figure is
In the conventional example, the transmission state when time slots are allocated equally to each communication control device 2 to 4 is shown for comparison.

Note that in this figure, (2) to (5) indicate time slot allocation to communication control devices 2 to 5, respectively.

Figure 8 (A) (B) is the time chart (A) of Figure 7.
) When the time slot allocation method of the present invention and the conventional example shown in (B) is used to perform 20 consecutive transmissions from only the communication control device 2, each communication This shows the transmission 1i (X; the ratio of the time when transmission is actually performed during the i period) when allocating to the control device 2.

As is clear from this figure, in the conventional example, the transmission amount is as low as 25%, whereas in the embodiment of the present invention,
From the second period onwards, the transmission amount is 25% or more, which is an improvement in the amount of transmission compared to the conventional example.

Note that, in the present invention, once a certain communication control device starts transmitting, it is continuously assigned a time slot for a specified number of times or more (in the numerical example described above, 8 times or more), and then transmits. It is effective when doing so.

For example, if a specific communication control device performs transmission only five times in a row, the amount of transmission (%) will actually be lower than in the conventional example.

However, in general, the amount of data to be transmitted continuously is greater than the l time fixed number of times, and the length of the time slot and the values of B, C, and D can be set in advance. It is something.

In addition, in the above, the rewriting of the variable part of the third table 9 is
Although the case where the rewriting is performed every number of times specified by D of the first table 7 has been described, the rewriting may be performed for each transmission. In this way, the second table 8 and the second rain star date can be omitted.

(Effects of the Invention) According to the present invention, in a time division multiplex communication network in which data transmitted at one time from a communication control device is divided into a frame number of packets and transmitted, an appropriate number (number of words) of time slots can be changed. By having a fixed part and a fixed part, it is possible to increase the transmission opportunities of the communication control device that has transmitted in the past and is expected to transmit this time, which has the effect of increasing the transmission loss of the communication network as a whole. .

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional time division multiplex communication device, FIG. 2 is a time chart showing the allocation of time slots to each communication control device in FIG. 1 and their operations, and FIG. FIG. 4 is a schematic block diagram of an embodiment of the present invention; FIG. 4 and 6 respectively.
Flowchart for explaining the operation of the synchronization signal transmitter and microprocessor in the figure, FIG. 7(A)
(B) is a time chart showing a comparison of time slot allocation in the embodiment of FIG. 4 and the conventional example of FIG. 2;
8(A) and 8(B) are diagrams each showing the transmission amount in FIG. 7, and FIG. 9 is a block diagram showing another example of a conventional time division multiplex communication device. 1... synchronous control device, 2. R, 4, 5... Communication control device, 6... Setting device, 7.8.9... 1st to 6th
table, 10. I+...1st. 2nd register, 12
...Synchronization signal transmitter, 13...Distributor, 14...
Microprocessor Representative Patent Attorney Michihito Hiraki 24 Figure 5 Figure-chome 2-1 Hitachi Control Co., Ltd.

Claims (4)

[Claims] (1) It has a synchronous control device and a plurality of communication control devices connected to a communication line network, and the synchronous control device transmits a synchronization signal to the communication control device at regular intervals, and each communication control device performs synchronization. If there is transmission data, transmission is performed only in the time slots assigned by the synchronization signal transmitted from the control device, and if the time slots are consecutive and assigned, transmission can be performed continuously as long as there is transmission data6. In a time division multiplex communication device, which has a function of being able to receive all data even if continuous transmission is performed from a communication control device, and is further equipped with a distributor that distributes transmission data from each communication control device. The synchronization control device includes a rewritable table that stores an array of addresses of communication control devices that defines the order and number of time slots to be assigned to each communication control device within a cycle, and a means for detecting the presence or absence of transmission from a communication control device that has not been allocated; means for rewriting the table when the scheduled number of transmissions is detected; and a synchronization signal for each communication control device according to the contents of the table. 1. A time division multiplex communication device comprising: a synchronization signal transmitter for transmitting a synchronization signal. (2) The time-division multiplex communication device according to Patent No. 1, wherein the table includes a fixed part whose stored contents are fixed and a variable part whose contents can be rewritten. (3) The time division multiplex communication device according to claim 1 or 2, wherein the table is rewritten every time the communication control device transmits the scheduled number of times. . (4) The time division multiplex communication device according to Patent No. 2, wherein addresses of all communication control devices are stored at least once in the fixed part of the table. <<5>> It has a Sawata synchronous control device and a plurality of communication control devices connected to a communication line network, and the synchronous control device transmits a synchronization signal to the communication control device at regular intervals, and each communication control device If there is transmission data, transmission will be performed only in the time slots assigned by the synchronization signal transmitted from the control device, and if the time slots are consecutively assigned, transmission can be performed continuously as long as there is transmission data, and other In a time division multiplex communication device, which has a function of being able to receive all degrees of stiffness even when continuous transmission is performed from a communication control device, and is further equipped with a distributor that distributes transmission data from each communication control device, The synchronization control device includes a rewritable table that stores an array of addresses of communication control devices that defines the order and number of time slots to be assigned to each communication control device within one cycle, and a table for rewriting the table. a second table for storing contents; a means for detecting the presence or absence of a transmission from a communication control device to which it is assigned in each time slot; and means for rewriting the table when a scheduled number of transmissions is detected. and a synchronization signal transmitter that transmits a synchronization signal to each communication control device according to the contents of the table, and the contents of the second table are transmitted one word each time transmission is performed from the communication control device. A time division multiplex communication device characterized in that the address of the communication control device that transmitted the data is written at the end of the column.