JPH08314568A - Data gathering system - Google Patents

Abstract

PURPOSE: To properly manage time by simple constitution by allowing a data processor to transmit time data to each data gathering terminal and allowing each data terminal to store received time data to use it as time data of each data terminal of its own. CONSTITUTION: Managing systems 10 and 11 execute poling calling operation in a set order with respect to each data gathering terminals 20, 21, 22,... to send a poling packet to a communication path 12. An address with respect to a specified data gathering terminal to be accessed is set to a control part. In addition, a clock function provided for a computer such as the managing system reads the time of poling generation to generate the poling packet in the form of incorporating it. The poling packet is propagated by way of the data communication path and each data gathering terminal 20, 21, 22,... uses received time data as time data of each data terminal of its own.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data collecting system, and more particularly to a technique effectively used for collecting various data from a collecting terminal by polling.

[0002]

2. Description of the Related Art In a data collection system consisting of a data processing device such as a computer and a data collection terminal, measurement is performed at regular intervals, and when a certain event occurs, data is taken in at that time. In order to do so, each data collection terminal is provided with a time function. In this case, it is necessary to periodically correct the time difference from the management system side such as the data processing device.

[0003]

In the data collection system as described above, when the clock function in each of the data collection terminals varies or fluctuates, there arises an inconvenient problem such that the data generation time point is reversed. for,
It is necessary to manage the time of each data collection terminal with high accuracy. For this reason, it is necessary to regularly perform only the time management process at relatively short intervals, or to keep the entire system energized in order to maintain the clock function of each data collection terminal, or by using a battery or the like. There is a troublesome problem such as maintaining only the above clock function.

An object of the present invention is to provide a data collection system that can manage time properly with a simple structure. The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0005]

The outline of a typical one of the inventions disclosed in the present application will be briefly described as follows. That is, the data management device includes a data processing device that transmits and receives desired data via a data communication path to and from a data collection terminal having a plurality of interfaces for capturing digital data, and the data management device generates time data and stores the time data. Transmitted to each data collection terminal,
Each data terminal stores the received time data and uses it as its own time data.

[0006]

According to the above-mentioned means, the data collection terminal does not need a special clock function, and the data processing device can unify the whole time function.

[0007]

1 is a schematic block diagram of an embodiment of a data collection system according to the present invention. 10
Is a display in a data processing device such as a microcomputer. Reference numeral 11 denotes a computer main body that constitutes a management system in the above data processing device. Reference numeral 12 is a data communication path for exchanging data. The data collection terminal 20 is composed of the following parts. Reference numeral 13 is a control unit constituting the data collection terminal 20, 14 is a data acquisition unit, 15 is a connection cable thereof, and 16 is a data collection target device (information source) where the data collection terminal 20 collects data. .

The data collection terminal 20 and other data collection terminals 21 and 22 similar to the data collection terminal 20 are exemplarily shown. Each of these data collection terminals 20, 21, 22, etc.,
It is connected to the sweet potato type (daisy chain type). Each of these data collection terminals 20, 21, 22, etc.,
At least one management system (10, 11) is connected via a data communication path 12. Each data collection terminal is addressed using a number or the like so that it can be logically distinguished. The data communication path 12 uses a coaxial cable, uses a twisted pair wire,
Alternatively, it is composed of an optical fiber or the like.

FIG. 2 is a block diagram for explaining the polling operation in the data collection system. The management system (10, 11) performs a polling (calling) operation for each data collection terminal 20, 21, 22, ... In the set order. For example, a polling packet including a preamble, a control unit, an information unit, and a postamble is sent to the communication path 12. An address for a specific data collection terminal to be accessed is set in the control unit.

The polling packet propagating through the communication path 12 is transmitted to all the data collecting terminals 20, 21, 22 ... Each of the data collection terminals 20, 21, 22 ... Can recognize whether or not the polling is for itself by recognizing the address information of the polling packet capture controller. If it is recognized that the polling is for itself, the measured and held data is sent to the management system as a response packet. An example of such a system is HDL.
It is well known as C (High Level Data Link Control) procedure or basic procedure.

In the above HDLC procedure or the like, as shown in FIG. 2, a preamble for indicating the beginning of data, a control unit for describing a communication command, an information unit for inserting data, and the end of a data packet. It is composed of a postamble and so on. The information section can be omitted if necessary. A cyclic redundancy check code (CRC code) for error detection is incorporated in the control unit, the information unit, and the like.

FIG. 3 shows an operation diagram for explaining the polling operation. In the example of the figure, the board 1, the board 2, the board 2, the board 3 as the data collection terminals are polled in the order of the board 1, the board 2 and the board 3 as the data collection terminals and the responses corresponding thereto.
The measurement data collected in step 1 is taken into the host (management system).

In this embodiment, in the data collection system as described above, each data collection is performed in order to perform measurement at regular intervals and to capture data at a certain time when an event occurs. The terminal is provided with a memory circuit that operates as a substantial clock circuit.

FIG. 4 is a block diagram showing an embodiment of the polling packet used in the present invention. In the data collection system of this embodiment, as shown in the figure, the time data part is inserted between the control part and the information part of the polling packet. That is, the clock function of the computer such as the management system reads the time when polling occurs, and the polling packet is generated in a form in which it is incorporated.

The polling packet is propagated through the data communication path. Since the data communication path is the common bus system as described above, each data collection terminal 2
Polling packets having time data arrive at 0, 21, 22, ... At approximately the same time. The above packet is
Since the time data is inserted, as shown in the flowchart of FIG. 5, the address part is taken out in (1), and the time data is taken out and stored in the time buffer (memory circuit) in (2). After writing, the address comparison is performed in step (3), and if the address does not match with the address assigned to itself (≠), the process ends. That is, the data collection terminal in this case simply performs the clock operation. On the other hand, if the address matches the address assigned to itself (=), the response packet of (4) is transmitted in addition to the above clock operation, and the process is terminated.

In FIG. 4, when data is taken in by the measuring unit 16 in FIG. 1, the data collecting terminal associates the time data in the time buffer with the taken data in a one-to-one correspondence with data 1, data 2, and data. 3, data 4, ... Are sequentially written in the data buffer. Then, when polling corresponding to the address assigned to itself is generated, the acquired data stored in the data buffer and the time are inserted as a pair in the information part of the response packet and sent to the management system. The format of this response packet is the same as the overall format of the polling packet, and the only difference is the code of the control unit.

FIG. 6 is a flow chart for explaining the data collection operation. The data collection as described above is performed depending on the function of each data collection terminal, such as when the data is measured at regular intervals based on the time data and when the signal from the connected device changes. In (1), data is fetched from each input port. In (2), the time data is taken out from the time buffer and made to correspond to the data from the input port in a one-to-one correspondence. Then, in (3), it is written in the data buffer (data packet buffer), and the process ends.

In this embodiment, in each data collecting terminal, a memory circuit for storing time may be added instead of the clock circuit having the reference oscillator. Moreover, when the system does not operate, the power supply is not shut off and the time data in the storage circuit is not stored. This greatly simplifies handling.

In this embodiment, the polling operation is used as described above to store time-varying time data in each data collection terminal in real time, so that the entire data collection system has a computer body or the like. It is possible to have a highly accurate clock function that is unified with the clock function. As a result, it is possible to avoid the inconvenience that the data generation time points are reversed due to the time difference between the data collection terminals.

The effects obtained from the above embodiment are as follows. That is, (1) the data management device includes a data processing device for exchanging desired data via a data communication path with a plurality of data collection terminals having an interface for capturing digital data, and the data management device generates time data. By transmitting time data to each data collection terminal, each data terminal stores the received time data and uses it as its own time data, the data collection terminal does not need a special clock function. Further, the effect that the whole can be unified by the same time system by the data processing device is obtained.

(2) Each data collection terminal is accessed by the polling operation. By inserting the time data in the polling packet in the polling operation, the special time setting operation becomes unnecessary and the system The effect that the efficient operation of can be realized can be obtained.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention of the present application is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say. For example, instead of using the polling operation, a time setting operation may be inserted at regular time intervals to realize the clock function of the entire system. In this case, the data transfer operation is limited by the amount of time setting operation inserted at regular intervals, but there is no problem in a system in which the period for data collection may be relatively long. In such a system, since the polling cycle becomes long, it is more efficient to divide the clock operation and the original polling operation separately.

When the signal handled by the measuring section is an analog signal, the captured analog signal is internally converted into a digital signal. A main management system and a sub management system may be connected to the data communication path.
In this case, the above-mentioned clock operation may be realized only by the main management system or by both depending on the operation. This invention is a CIM using a computer.
It can be widely used for various data collection systems such as.

[0024]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows. That is, the data management device includes a data processing device that transmits and receives desired data via a data communication path to and from a data collection terminal having a plurality of interfaces for capturing digital data, and the data management device generates time data and stores the time data. Transmitted to each data collection terminal,
Each data terminal stores the received time data and uses it as its own time data, so that the data collection terminal does not need a special clock function,
Moreover, it is possible to unify the whole by the same time system by the data processing device.

Each data collection terminal is accessed by the polling operation. By inserting the time data in the polling packet in the polling operation, the special time setting operation becomes unnecessary and the system efficiency is improved. It is possible to realize various operations.

[Brief description of drawings]

FIG. 1 is a schematic block diagram showing an embodiment of a data collection system according to the present invention.

2 is a configuration diagram for explaining a polling operation in the data collection system of FIG. 1. FIG.

FIG. 3 is an operation diagram for explaining the polling operation of FIG.

FIG. 4 is a configuration diagram showing an embodiment of a polling packet used in the present invention.

FIG. 5 is a flow chart for explaining a transmission polling interrupt process in the polling operation according to the present invention.

FIG. 6 is a flowchart for explaining a data fetching process in the polling operation according to the present invention.

[Explanation of symbols]

10 ... Display (management system), 11 ... Computer main body (management system), 12 ... Data communication path, 13
... Control unit of data collection terminal, 14 ... Data acquisition unit of data collection terminal, 15 ... Connection cable of data collection terminal, 16 ... Data collection target device (measurement device), 20-2
2 ... Data collection terminal.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takayuki Inoue 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd. (72) Inventor Norio Maru 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd. (72) Inventor Harumichi Yoshino 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Electronic Device Division

Claims (2)

[Claims] 1. A data collection terminal including a plurality of interfaces having an interface for taking digital data, a data processing device for transmitting and receiving desired data from each data collection terminal, and between the data processing device and each data collection terminal. And a data communication channel connecting the data processing device, the data processing device generates time data, transmits the time data to each data collection terminal, and each data terminal stores the received time data and stores it. A data collection system characterized by being used as time data of. 2. The data processing device accesses each data collecting terminal by a polling operation, and the time data is inserted in a polling packet in the polling operation. Data collection system.