JP3356802B2 - Data transmission adapter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

This invention relates to a relatively small LA.
The present invention relates to a data transmission adapter suitable for use in N connection.

[0002]

2. Description of the Related Art Conventionally, this type of adapter generally converts only a physical interface condition such as a signal level between a data processing device to be connected and a communication path. Therefore, for example, in a data transmission system that uses a personal computer as a master and transfers data to and from a slave such as a programmable logic controller (hereinafter abbreviated as “PLC”),
The communication procedure program provided in the master unit periodically polls the data of each slave unit and stores the data extracted from the slave unit in the memory of the master unit, so that the slave unit itself can actively In many cases, a passive configuration that does not transmit data is adopted.

[0003]

However, in the above-described data transmission system, since one master unit controls all data transmission, all the slave units connected via the communication path are the same. As a result of being required to transfer data according to the communication procedure of the above, connection between heterogeneous models is not only extremely difficult, but also special master unit for data communication is specially required.
There was a problem that lacked expandability of the entire system.

The present invention has been made in view of the above-mentioned problems, and an adapter capable of performing data transmission without limiting the type of data processing apparatus to be connected while maintaining a relatively simple configuration. The purpose is to provide.

[0005]

To achieve the above object Means for Solving the Problems], in the according data transfer adapter of the present invention, as shown schematically the overall arrangement in FIG. 1, the de
The data transmission adapter (22) is
(0) To perform data communication using a model-specific communication protocol
Having a communication program of
Adapter for performing serial data processor (10) and the inter-device communication unit for transmitting and receiving data (14), the transmission and reception of data to and from other adapter connected via said communication path (12) (22) Communication unit
And (16), the device communication unit (14) and adapter communication unit (16)
And a data storage unit (18) for transferring data between the two communication units (14) and (16).

According to the present invention, there is further provided a data storage section (18).
Inside, each data processing device connected via the communication path (12)
While providing the data of (10) as shared data (20),
The communication unit between adapters (16) is at least a communication unit between devices (14)
Data (20) in the data storage unit (18) updated by
To the other adapters (22) via the communication path (12), while transmitting the shared data (20) to the other adapters (22).
Update with the shared data (20) received from
(14) corresponds to the updated shared data (20).
Data relating to the data processing device (10) is transmitted to the data processing device.
Submit .

[0007]

According to the above-described configuration, the inter-device communication unit (14) provided in each adapter (22) accesses the data storage unit (18) at an appropriate time to update the shared data (20), or Data processing device that extracts data from shared data (20)
Send to (10).

On the other hand, the inter-adapter communication section (16) transmits at least data updated by the inter-apparatus communication section (14) out of the shared data (20) in the data storage section (18), for example, at a predetermined minute time interval. To perform broadcast transmission to another adapter (22). Then, the inter-adapter communication unit (1
6) is the shared data (2) in the data storage unit (18).
By performing the update of (0), data of substantially the same content is basically maintained at all adapters (22) at all times. And
When the existence data (20) is updated, the inter-device communication unit (14)
Of the data (20), the data processing device (10)
Data to the data processing device (10).

Therefore, the data storage unit (18) and the data processing device (1) are used for each adapter (22) by using the inter-device communication unit (14).
Only necessary data is passed between (0)
Data is exchanged between the data processing devices (10) connected via (2).

[0010]

According to the present invention, as described above, all the data processing units (10) connected via the communication path (12) are commonly used in the data storage unit (18) of each adapter (22). Shared data
(20) is set and its contents are updated by broadcast to all the adapters (22), so the data exchange between multiple data processing units (10) can be compared. It can be easily performed while maintaining a simple structure. Sa
In addition, the inter-device communication unit (14)
(0) To perform data communication using a model-specific communication protocol
Communication program. Therefore, the connected machine
Communication programs compatible with various communication protocols
By individually downloading each plug (22),
Do not have multiple communication protocols in the adapter (22).
Adapter for any data processing device (10)
Data can be configured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 4, the present invention uses data of three PLCs (24a) (24b) (24c) provided as a data processing device, as shown in FIG.
This will be described based on an example in which control is performed centrally using a "personal computer") and a control system in which the control state of each PLC (24) is displayed by one display control device (28). The present invention is not limited to this, and it goes without saying that the type or number of connected data processing devices can be changed as appropriate.

The data transmission adapter according to the present invention (22)
As shown in FIG. 2, a first connector (34) is attached to one side surface (32) of a flat main body case (30) having a substantially rectangular planar shape, and the other side surface (36). ) Second
A connector (38) is provided, and a control circuit (40) shown in FIG. 3 is built therein.

The first connector (34) is an RS-232C standard often used for serial transmission of data in various data processing devices such as a personal computer (26). As shown in FIG. 3, a male pin (4
By fixing the connector equipped with 2) to the case side (32), it can be inserted into and removed from the connector (46) equipped with the female pin (44) on the data processing device (10) side without connecting cables. Freely and directly attached. Further, the first connector (34)
A mounting screw (48) is provided on both sides of the first connector (34), and the mounting state of the first connector (34) is fixed by screwing with a fixing screw (50) provided on the data processing device (10) side.

The second connector (38) is of a type often used for telephones generally called a "modular connector", and its jack (52) side is connected to the side surface (30) of the main body case (30). 36) and fix the two electrodes (54) of the jack (52) to the body case.
They are connected in parallel within (30).

As the control circuit (40), a program control type using a one-chip microcomputer is used, and a CPU (56) for controlling the whole circuit and a ROM (58) for storing a program for performing the control are provided. ), A RAM (60) for temporarily storing various data, and a first for inputting / outputting data to / from the outside.
And a second serial data interface (62) (64)
(Hereinafter, abbreviated as “SIO”) are connected in parallel via an internal bus (66).

The first SIO (62) is an RS-232
It has a circuit configuration substantially the same as that of the related art that enables input / output of data according to the C standard.
It is connected to each pin (42) of the connector (34).

In this embodiment, a plurality of adapters (22) can be connected as a second SIO (64) in the form of a bus.
-485 standard is adopted. Specifically, the data output line (70) by the driver (68) and the receiver
A balanced communication path (12) provided with two data input lines (74) by (72), and a maximum of 30 sets (5 sets in this embodiment) ) Are connected in parallel with each other.

FIG. 4 shows the data transmission adapter (2
FIG. 3 is an explanatory view showing a specific use state of 2), wherein one A is connected to the serial data communication connector (46) in each of a plurality of data processing devices that are to transmit data to each other according to the present invention. The first connectors (34) of the five adapters (22) indicated by .about.E are directly connected and fixed. That is, the personal computer (26) is connected to the adapter A as a virtual master device, and the adapters B, C, E are connected to the first to third PLCs (24a), (24b), (24c). The display control device (28) is connected to the adapter D.

Further, a jack (52) of a second connector (38) provided for each of the adapters A to E is connected to a modular plug (75) at both ends.
A communication path (12) is constructed by connecting a series of buses using a communication cable (76) provided with a cable, and reflection is prevented by terminating both ends of the communication path (12) with a predetermined resistor (78). I do.
A power supply unit (82) for converting a commercial AC power supply (80) to a low-voltage DC voltage is provided in the middle of the communication path (12), and a communication cable (76)
A necessary DC drive voltage is supplied to all the adapters (22) through two power supply lines (84) provided in parallel with the communication path (12).

On the other hand, the second connector (38) has an electrode (54) for grounding and power supply, and has a power supply line (84).
A DC voltage is sent in parallel from the outside of the main body case (30) to all the adapters (22) through the main body case (30), while a DC-DC converter (86) is provided inside the main body case (30), and a predetermined It is configured to supply the driving voltage of.

The ROM (58) in the above-mentioned control circuit (40)
Some or all of them are electrically rewritable, such as a flash EEPROM. Prior to use, a personal computer (26) for system development uses an adapter (34) through a first connector (34). 22) A program for communication between adapters that enables mutual data transmission between (22), data transmission between the data processing device (10) to be connected via the first connector (34) and the adapter (22) By individually downloading the inter-device communication program or other necessary programs, the specific functions or operating characteristics of each adapter (22) can be changed individually for each adapter (22). I can do it.

In particular, since the data processing device (10) to which the adapter (22) is connected has a significantly different communication protocol for each model, an inter-device communication program suitable for the communication protocol of the model to be connected is stored in each adapter (10). 22) By enabling individual download and storage for each
An adapter corresponding to an arbitrary data processing device (10) can be easily configured without having a plurality of communication protocols in (2).

Further, by making it possible to download a program for realizing other functions as required, the function of the adapter (22) can be further enhanced, and the data processing device (10) has a higher processing capability. The burden can be further reduced.

It is possible to individually download the system parameter information, which will be described in detail later, into each adapter (22) simultaneously with the various programs described above. However, it is expected that this type of system parameter information is frequently changed with the expansion of the system. Therefore, by centrally registering this information in advance in the virtual master unit in the adapter (22) and sending it to a plurality of slave units using a network line when the system is operating, the system can be configured. It is preferable because it can easily respond to changes.

Further, on the RAM (60), a storage area (88) of the shared data (20) used in common by all the adapters (22) is provided for each of the adapters (22) as illustrated in FIG. It is set to be distinguished. For example, in the present embodiment, five adapters A to E connected via a communication path (12) correspond to five adapters (22),
The five sets of shared data (20) A to E can be partitioned and stored as node information, and a predetermined number of data (in this embodiment, three data 1 to 3 in this embodiment) ) Is set in advance, and the 15 data items A1 to E3 are stored separately.

The above-mentioned system parameter information includes a transmission table (90) and a reception table (92) which are set in one-to-one correspondence with all the shared data (20). 90) and (92), the data handled for each adapter (22) can be individually set and changed.

In the transmission table (90), the shared data (20)
Is set, the memory address on the data processing device (10) to which the adapter (22) is connected and the number of bytes to be taken out of the data from the address are set for each individual data constituting. For example, in the case of the adapter B illustrated in FIG. 5A, data B1 is stored in the memory 93 of the PLC 24a.
Eight bytes of data B2, eight bytes of data B2, and two bytes of data B3 are taken out and can be stored in the storage area (88), and transmitted to another adapter (22) via the communication path (12). This is the node information unique to the adapter B.

On the other hand, the reception table (92) selects only necessary data from the node information sent from the other adapter (22) via the communication path (12) as described above and incorporates it into the inside. Be prepared for That is, the transmission table
Based on (90), set the number of bytes in the data area that does not require data update to zero, or do not set the corresponding item in the table (92), so that only the set number of bytes from the received data Then, only the necessary part in the shared data (20) is selected and updated.

Next, the operation of the adapter B shown in FIG. 4 will be described in further detail with reference to the explanatory diagram of FIG. 5A and the flowchart of FIG.

The PLC (24a) connected to the adapter B is
Since it does not have an active access function by itself, the adapter B is configured to perform an active operation.
That is, one adapter (22) is loaded when various programs are loaded or after each adapter (22) is connected to the LAN.
In the present embodiment, the system parameter information transmitted from the adapter A which is virtually set as the master unit by broadcast communication via the communication path (12) is stored in the step (10) in FIG.
When the data is received in 1), the transmission table (90) and the reception table (92) of FIG. 5A are set in step (102). The data transfer operation starts.

In the communication between the adapters, when it is confirmed in step (103) that the node information has been transmitted by broadcast from another adapter (22) connected via the communication path (12), Referring to the receiving table (92) in step (104),
It is determined whether or not the data is data used by the adapter B. For example, if the data of A3 is transmitted from the adapter A as the node information, the reception table (92)
Since it is known that 2 bytes are set from the data, the data is sent to the storage address of the shared data (20) in step (105) to update the data.

Further, if it is determined in step (106) that the set time of, for example, about 100 milliseconds has elapsed, B1
The node information of the adapter B specified by B2 and B3 is
In step (107), another adapter (22) through the communication path (12)
, So that the node information in all the adapters (22), that is, the shared data (20) always coincides.

On the other hand, the communication between the devices is performed in step (108).
Check the management information on the LC (24a) side continuously, step (109)
When a change is recognized in step (110), node information of B1 to B3 is read from a predetermined address on the PLC (24a) side in step (110), and management information inside the adapter (22) is updated in step (111). Further, in step (112), the old data (98) before update is compared with the current shared data (20), and if it is determined in step (113) that the data has changed, the change information is determined in step (114). Is sent to the PLC (24a) to update the data inside the PLC (24a).

It should be noted that all of the adapters (22) indicated by A to E can be constructed by using those which perform the above-mentioned active operations. However, in the present embodiment, the personal computer (26) and the display control device (28) utilize the fact that they have an active access function to the adapter (22), and FIG. Both use a passive adapter (22) whose operation is illustrated in FIG.

That is, the communication between the adapters performs substantially the same operation as that of the active adapter (22). However, in the inter-device communication, if it is confirmed in step (120) that there is a data rewrite request from the personal computer (26), the necessary node information is read in step (121), and step (122)
Then, the management information inside the adapter (22) is forcibly rewritten with the data. On the other hand, in step (123), the personal computer (2
When it is confirmed that the data read request is received from the 6) side, the corresponding data is transmitted to the personal computer (26) in step (124).

The data transmission between the adapters (22) is as follows.
Although the system is configured to periodically and forcibly perform the update every set time regardless of the presence or absence of the data update, the data may be transmitted only when the data update is confirmed. In addition, the amount and range of data to be transmitted at one time can be changed as appropriate.

In addition to the bus connection between the adapters,
An arbitrary LAN connection such as a star connection or a ring connection can also be made. In this case, it is needless to say that the shape of the socket and the communication standard are appropriately changed according to each connection method.

Further, instead of supplying power for the adapter from the second connector side via the communication cable, power is supplied from the data processing device (10) side via the first connector.
A dedicated power supply built in or provided separately may be used. Further, the communication path is not limited to a wired path, and can be implemented in a substantially similar manner even when wireless.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a basic configuration of the present invention.

FIG. 2 is a perspective view showing an external shape of an embodiment of the adapter according to the present invention.

FIG. 3 is a block diagram illustrating an example of a control circuit.

FIG. 4 is an explanatory diagram showing an example in which an adapter is connected to a LAN.

FIG. 5 is an explanatory diagram showing a data update procedure;
(A) shows an active type and (b) shows a passive type.

FIG. 6 is a flowchart showing an operation procedure in an active adapter.

FIG. 7 is a flowchart showing an operation procedure in a passive type adapter.

[Explanation of symbols]

 (10) Data processing unit (12) Communication path (14) Communication unit between devices (16) Communication unit between adapters (18) Data storage unit (20) Shared data (22) Adapter (24) PLC (26) Personal computer (28 ) Display control device (34) First connector (38) Second connector (40) Control circuit (76) Communication cable (88) Storage area (90) Transmission table (92) Reception table

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Juri Okasaka 8-52, Nankohigashi, Suminoe-ku, Osaka-shi, Osaka Digital Co., Ltd. (56) References JP-A-2-154550 (JP, A) JP-A-2-244928 (JP, A) JP-A-4-16795 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04L 29/10 H04L 12/28

Claims (1)

(57) [Claims] 1. A data transmission adapter (22) which is individually arranged for a plurality of data processing devices (10), is connected via a communication path (12), and enables data transmission to each other. Each of the data transmission adapters (22) performs data communication using a communication protocol specific to the model of the corresponding data processing device (10).
Communication program for performing
The gram the data processing apparatus (10) and the inter-device communication unit for transmitting and receiving data (14), the transmission and reception of data to and from other adapter connected via said communication path (12) (22) an adapter communication unit (16) to perform, be between the device communication unit (14) adapter communication unit (16), both the communication unit (14) (16) data storage unit for transferring data between (18) and wherein the data storage unit in (18), together comprising as shared data (20) the data of each data processing device (10) connected via a communication path (12), between the adapter communication The unit (16) is at least an inter-device communication unit (14)
Data (20) in the data storage unit (18) updated by
To the other adapters (22) via the communication path (12), while transmitting the shared data (20) to the other adapters (22).
Updated with shared data (20) received from the inter-device communication unit (14), the updated shared data (20)
The data related to the corresponding data processing device (10) is
A data transmission adapter for transmitting data to a data processing device (10) .