JPH11122209A - Time-divisionally multiplexing/transmitting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To time-divisionally multiplex and transmit non-periodical data while the scales of a software processing and hardware are reduced by generating a transmission code rule error, setting it as the header of a frame and adding a data string obtained by time-divisionally multiplexing non-periodical data and periodical data, whose transmission periods change according to data quantity, to the header so as to transmit it. SOLUTION: Multiplexing parts 25a and 25b generate conversion data 19a and 19b from non-periodical data 17 and periodical data 18 based on the same sampling clock 16. A serial/parallel conversion part 26 generates the pulse width which is twice as much as a DMI code as the header 14, duplexes/ multiplexes conversion data 19a and 19b based on a secondary multiplex sampling clock 20 to generate a data part, adds the data part to the header 14 and outputs it as a transmission frame 21. Thus, hybrid multiplex transmission is realized with a processing by simple hardware and a transmission unit can inexpensively be constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a time-division multiplexing transmission method, and more particularly, to a method for transmitting irregularly transmitted data such as contact information transmitted at an irregular period and periodically transmitted periodic data such as voice data. The present invention relates to a time division multiplex transmission method for multiplex transmission.

[0002]

2. Description of the Related Art FIG. 5 shows a time division multiplex transmission system corresponding to a conventional time division multiplex transmission method. Transmission equipment 1a, 1
b, 1c, 1d are such that the whole forms one loop,
They are interconnected by a transmission line 2. Transmission equipment 1a
To 1d each include a transmission unit that transmits data to another transmission device and a reception unit that receives data from another transmission device.

[0003] A frame 3 circulates in the loop formed by the transmission path 2. When multiplex transmission of the irregular period data 4 (for example, instrumentation signals such as contact points and analog information) to the frame 3 is performed, the irregular period data 4 transmitted irregularly by software and hardware possessed by the transmission devices 1a to 1d. Is processed into periodic data 5, and the periodic data 5 is allocated to a channel in the frame 3 and transmitted. Thereby, data having different transmission periods are synchronized with each other, and can be transmitted in the same frame 3.

FIG. 6 shows a configuration of a transmission device to which a conventional time division multiplex transmission method is applied. The transmission device includes a data bus 6, an MPU (microprocessor unit) 7, a reception control unit 8, a channel control unit 9, and a transmission control unit 10. The irregular-cycle data 4 included in the frame 3 on the transmission path 2 is taken in by the reception control unit 8 and transmitted to the data bus 6 via the MPU 7.
The variable-period data 4 is converted into periodic data 5 by the MPU 7 and transmitted together with other periodic data by the transmission control unit 1.
0 is transmitted to the transmission path 2. A frame synchronization signal 11a is provided from the reception control unit 8 to the MPU 7, the channel control unit 9, and the transmission control unit 10. The frame synchronization signal 11b is transmitted between the channel control unit 9 and the MPU 7.

[0005] In FIG. 6, the transmission order of the variable-length data 4 passed from the data bus 6 is determined by the MPU 7. The indefinite period data 4 in the order of transmission is converted into periodic data 5 by the MPU 7 in synchronization with the frame synchronization signal 11a detected by the reception control unit 8. The periodic data 5 is sequentially assigned to a predetermined time slot (a fixed time unit) of the frame 3 by the channel control unit 9. Frame 3 created in this way is
The signal is transmitted from the transmission control unit 10 to the transmission line 2 in synchronization with the frame synchronization signal 11a, and is transmitted to another transmission device via the transmission line 2.

[0006]

However, according to the conventional time-division multiplexing transmission method, when data transmitted at an indefinite period is multiplexed and transmitted in synchronization with periodic data, the data periods of each other are synchronously transmitted. The scale of hardware such as software for converting data into possible data and a time slot generation unit for controlling data transmission is increased. As a result, the development period of the transmission equipment is prolonged and the cost is increased.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a time division multiplex transmission method which enables time division multiplex transmission of indefinite period data while reducing the scale of software processing and hardware.

[0008]

According to the present invention, in order to achieve the above object, a transmission coding rule error is generated, and the transmission coding rule error is used as a header of a frame. A time-division multiplexing transmission method characterized by adding a data sequence obtained by time-division multiplexing of data and periodic data periodically generated to the header and transmitting the header.

[0009]

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

First, the outline of the present invention will be described. In the case of time-division multiplexing of data input at different periods, since the data amount of the indefinite period data is not constant, it is necessary to construct a time slot of the converted data. Therefore,
When time-division multiplexing of data input at different periods, a header due to a transmission coding rule error is provided at the beginning of the data to construct a time slot for periodic data, and after this header, indefinite period data (instrumentation data, etc.) And time-division multiplexed with periodic data (such as audio data) and transmitted. The receiving unit can determine the order of receiving data time slots by detecting a header due to a transmission coding rule error.

According to the above method, a time slot control unit and a software processing unit (MPU) for data conversion and the like, which are conventionally required, become unnecessary. As a result, the indefinite-period data and the periodic data can be transmitted in a time-division multiplexed manner with simple hardware, so that the cost of the transmission equipment and the development period can be reduced.

FIG. 1 shows a configuration of a transmission unit of a transmission device to which a time division multiplex transmission method according to an embodiment of the present invention is applied.
A multiplexing unit 14a for generating conversion data 13a as first conversion data from the indefinite periodic data 12; a multiplexing unit 14b for generating conversion data 13b as second conversion data from the periodic data 15; It comprises a serial / parallel converter 16 for multiplexing the converted data 13b. Multiplexer 14a and multiplexer 14b
Performs sampling based on the sampling clock 17 at the same timing. Serial / parallel converter 1
6 generates a pulse width twice as large as that of the DMI code as a header 18 (transmission code rule error), and performs second-order multiplexing on the first-order multiplexed conversion data 13a and 13b based on a second-order multiplexing sampling clock 19. To generate a data portion. This data portion is added to the header 18 and output to the transmission path 2 as a transmission frame 20.

FIG. 2 shows a configuration of a receiving unit of a transmission device to which the time division multiplex transmission method according to the embodiment of the present invention is applied.
The receiving unit includes a header detecting unit 21, a frame monitoring unit 22, a shift register 23, and a latch lock generating unit 24. The header detection unit 21 extracts the header 18 from the transmission frame 20 received from the transmission path 2 and sends it to the frame monitoring unit 22 and the shift register 23. The frame monitoring unit 22 monitors the transmission cycle and length of the header 18 of the transmission frame 20 from the header detection unit 21, and when detecting an error in the received data, the latch lock generation unit 2
Then, the information of "abnormal" is sent to No.4. The latch lock generation unit 24 generates a latch clock 25 based on the header 18 detected by the header detection unit 21, and
Send to The shift register 23 sequentially shifts the data in the transmission frame 20 from the shift register 23 based on the latch clock 25 given from the latch lock generation unit 24, and separates and outputs the data into the indefinite-period data 12 and the periodic data 15. .

FIG. 3 shows a configuration of a transmission frame in the time division multiplex transmission method of the present invention.

In FIG. 3, reference numeral 26 denotes an indefinite-period frame (data 26-1 to 26- _n ) composed of indefinite-period data (data 26 _{-1 to} 26- _n ) in which the generated data period changes (thus, the frame period also changes). Reference numeral 27 denotes a periodic frame (corresponding to the converted data 13b in FIG. 1) constituted by periodic data (data 27 _{-1 to} 27 _-n ) in which data is generated at a constant period. . In the case of further multiplexing the indefinite-period frame 26 and the periodic frame 27 (if the indefinite-period data and the periodic data are primary-multiplexed, this corresponds to the secondary multiplexing), two types of asynchronous transmission frames (indefinite-period) having different generation periods are used. The periodic frame 26 and the periodic frame 27 are sequentially multiplexed in bit units, and a transmission coding rule error is provided as a header 18 at the head of each multiplexed data (frame) 28 each time. As a result,
Aperiodic frame 26 and periodic frame 2 that are asynchronous
7 can be handled as if it were synchronous transmission, and the indefinite-period frame 26 and the periodic frame 27 can be multiplex-transmitted with a small-scale hardware configuration.

The frame provided with the header 18 is
And is received by another transmission device via. By detecting the header of the transmission coding rule error in the receiving unit, it is possible to determine the order of receiving the data time slots, so that it is possible to separate the data into irregular data and periodic data.

As described above, the time slot control unit and the software processing unit for data conversion and the like (MPU 7 in FIG. 6), which are necessary for the conventional transmission equipment, are no longer necessary. 26 and the periodic data 27 can be transmitted by time division multiplexing. Further, since a transmission coding rule error is used as the header 18, a redundant portion such as an address can be omitted.

Next, a process for adding the header 18 will be described.

FIG. 4 shows a process in the time division multiplex transmission method of the present invention. In the figure, (a) shows the operation in the transmitting unit in FIG. 1, and (b) shows the operation in the receiving unit in FIG.

First, the processing of the transmission unit will be described. The irregular data 12 included in the irregular frame 17 and the periodic data 15 included in the periodic frame 18 are converted data 13a, 13a by the same sampling clock 17.
13b is sampled. The two types of converted data 13a and 13b sampled from the indefinite-period data 12 and the periodic data 15 at the same timing are further subjected to parallel / serial conversion (second Next multiplex). At this time, the receiving party (another transmission device) receives the indefinite periodic frame 12 and the periodic frame 1
5 and the order of data (order of arrival of frames on the receiving side)
DMI is added to the front of the conversion data 13a so that
(Defferential Mark Inversion) A transmission frame 20 is configured by providing a transmission code rule error header 18 with a pulse width twice as large as the code. This transmission frame 20 is transmitted to the transmission path 2.

The transmission coding rule error as the header 18 is as follows:
Secondary multiplex sampling clock 1 for performing secondary multiplexing
9 is extracted from the system clock when the header (DMI
It is generated by adding a clock having a width that is 1/2 times the sampling width of the coding rule error) area, that is, the cycle width of the conversion data 13a (13b).

Next, the processing of the receiving unit will be described. The latch 18 is generated by detecting the header 18 from the received transmission frame 20. At this time, the transmission cycle and the length of the header 18 are monitored to monitor the received transmission frame 20. If the received data is erroneous, no further reception processing is performed. When the transmission frame 20 is normal, the received data is sequentially shifted. The data 29 shifted by one clock and the data 30 shifted by two clocks are latched at the timing of the latch clock 22, and the converted data 13a and 13b are shifted. Reproduce. The converted data 13a and 13b thus reproduced are sampled by the respective sampling clocks 19 and restored to the original data indefinite-period data 12 and periodic data 15.

In the above-described embodiment, one secondary multiplexing unit is used. However, by using a plurality of secondary multiplexing units or by increasing the transmission cycle speed, multiplex transmission of a plurality of data having an irregular period can be performed. Will be possible.

Also, the transmission line 2 has been described as a wired example.
An optical fiber may be used, or a radio wave such as an electric wave or an infrared ray may be used.

[0025]

As described above, according to the data multiplexing transmission method of the present invention, a transmission coding rule error is generated and is used for a frame header, so that hybrid multiplexing transmission can be performed by simple hardware processing. Therefore, the transmission device can be configured at low cost. Further, the development period can be shortened.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a transmission unit of a transmission device to which a time division multiplex transmission method according to an embodiment of the present invention is applied.

FIG. 2 is a block diagram showing a configuration of a receiving unit of a transmission device to which the time division multiplex transmission method according to the embodiment of the present invention is applied.

FIG. 3 is a configuration diagram showing a configuration of a transmission frame in the time division multiplex transmission method of the present invention.

FIG. 4 is a timing chart showing processing in the time division multiplex transmission method of the present invention.

FIG. 5 is a block diagram showing a schematic configuration of a time division multiplex transmission system corresponding to a conventional time division multiplex transmission method.

FIG. 6 is a block diagram showing a configuration of a transmission device to which a conventional time division multiplex transmission method is applied.

[Explanation of symbols]

 1a, 1b, 1c, 1d Transmission equipment 2 Transmission path 12 Indefinite period data 13a, 13b Conversion data 14a, 14b Multiplexer 15 Periodic data 16 Serial / parallel converter 17 Sampling clock 18 Header 19 Secondary multiplex sampling clock 20 Transmission flame

Claims (3)

[Claims] 1. A transmission coding rule error is generated, the transmission coding rule error is used as a header of a frame, and data obtained by time-division multiplexing of indefinite period data whose transmission period changes depending on the data amount and periodic data periodically generated. A time-division multiplexing transmission method, wherein a column is added to the header for transmission. 2. The time division multiplex transmission method according to claim 1, wherein the transmission code rule error is a signal having a pulse width twice as large as a DMI code. 3. The data stream generates first and second conversion data from the indefinite-period data and periodic data based on the same sampling clock, and converts the first and second conversion data to a second order. 2. A signal generated by performing serial / parallel conversion based on a sampling clock for multiplexing and performing quadratic multiplexing.
The time-division multiplexing transmission method described.