JPH11177592A - Data transmitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data transmitting device by which the reliability of data of a device to be connected to a bus is improved with simple configuration. SOLUTION: This data transmitting device is provided with transmitters 1 and 2 for outputting a transmission frame to the bus by including last time transmission channel data at the time of transmitting the transmission frame which includes data of the plural channels, and other transmitters 3 and 4 for receiving the transmission frame flowing through the bus and continuously receiving the same channel data plural times.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for transmitting data such as a process amount.

[0002]

2. Description of the Related Art Conventionally, as a data transmission method, process data such as temperature collected by a slave station is transmitted by a slave station to a master station via a transmission line in response to a polling signal from the master station. There is a polling method in which after the processing, a polling signal is transmitted to another slave station again.

[0003]

However, in the polling method, since the master station is always required and the polling signal is always required, the apparatus is complicated, the response takes time, and the communication speed is insufficient. is there.

In transmitting and receiving data of a plurality of channels, there is a demand for improving reliability.

When data reception is inconvenient, data is usually obtained by retry and recovery processing is performed.
In the case of high-speed communication, there were times when it was too late.

An object of the present invention, in view of the above, is to provide a data transmission device having a simple configuration and improving the reliability of data of a device connected to a bus.

[0007]

SUMMARY OF THE INVENTION The present invention provides a transmission apparatus for outputting a transmission frame including data of a previously transmitted channel to a bus when transmitting a transmission frame including data of a plurality of channels, and receiving a transmission frame flowing through the bus. This is a data transmission device including another transmission device that continuously receives data of the same channel a plurality of times.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention. In FIG. 1, for example, an input device 1,..., An output device 2,... The output device 2,..., The arithmetic device 3,. Each of these devices is assigned a device number unique to the device, and data and the like can be transmitted using this device number.

The analog signal data such as temperature input to the input device 1 is subjected to necessary processing such as linearization and the like, and is given a unique device number of the input device 1 and output to the bus L as output data. Is output.

Then, the necessary data among the data flowing on the bus L is fetched by the output device 2 and the arithmetic device 3. For this reason, these capture devices include:
A device number assigned to output data of an input device or the like required by the capture device is set in advance as a capture number depending on which input device or the like needs output data.

For example, assuming that the data of the input device 1 is fetched by the output device 2 and the arithmetic device 3, the output device 2 and the arithmetic device 3 obtain the same number as the device number "01" of the input device 1 by the capture number " 01 ".

The output device 2 is the input device 1 corresponding to the acquisition number "01" of the data flowing through the bus L.
Only the data with the device number "01" is discriminated and selected, taken in, and output to the outside after predetermined processing.

The arithmetic unit 3 outputs the input device 1 corresponding to the acquisition number “01” of the data flowing through the bus L.
Only the data with the device number “01” is selected, determined and imported. Then, after performing other necessary calculations such as averaging, the unique device number “03” of the arithmetic unit 3 is added to the data.
And output to the bus L.

A management device 4 such as a personal computer is connected to the bus L to transmit set values to each transmission device and to grasp the overall status. In addition, the status of each transmission device is monitored and displayed on a display device as needed, and when an abnormal device that is not operating is found, the status is displayed on the display device and an alarm is issued to the outside, and the necessary Take action.

Now, consider a case where data of a plurality of channels of the input device 1 is taken in by the output device 2.
A packet (transmission frame) of shifted data for a plurality of channels is output from the input device 1 to the bus L.
For example, assuming that 5 data are sent for each transmission frame,
It is as follows.

CH1, CH2, CH3, CH4, CH5 CH2, CH3, CH4, CH5, CH6 CH3, CH4, CH5, CH6, CH7 CH4, CH5, CH6, CH7, CH8 CH5, CH6, CH7, CH8, CH9 ... In other words, as described above, when a plurality of data are set in each transmission frame and transmitted, the data including the data output last time is transmitted. By repeatedly outputting with shifting, it is used for recovery of erroneous transmission on the bus L. That is, in the case of reception by the output device 2, for example, as shown in FIG. 2, since each transmission frame flowing through the bus L is received and data of the same channel is continuously received a plurality of times, a certain transmission frame is lost. Even so, in the next transmission frame, data of the same channel number is acquired, and thereafter, data reception is repeated one after another to update the data content. Alternatively, a plurality of received data of the same channel may be compared, and when the contents of the data are the same, the data may be adopted and updated.

In the above example, the transmission devices 1 and 2 have been described as examples, but the same applies to the other transmission devices 3 and 4.

[0018]

As described above, the present invention provides a transmission apparatus for transmitting a transmission frame including data of a plurality of channels to a bus including data of a previously transmitted channel, and a transmission frame for transmitting the transmission frame including data of a plurality of channels. This is a data transmission device including another transmission device that receives and receives data of the same channel continuously multiple times. For this reason, the main station is not required, and the communication speed can be made sufficiently high. Since only a minimum of two devices and a bus are used, tens or hundreds or more of data and devices can be combined as far as the number permits. Can be easily, arbitrarily, and flexibly configured, and can easily and sufficiently cope with various systems, which is rich in flexibility and expandability, and effectively and efficiently. Further, since data of a plurality of channels is shifted and output to the bus, the reliability of the data can be improved, and it is extremely resistant to transmission failures during transmission. That is, since the received data of the same channel is taken in a plurality of times, the reliability of the data can be sufficiently ensured. Further, if a plurality of received data of the same channel are compared and the content of the data is the same, the data is adopted and updated, so that the reliability of the data is further improved.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing one embodiment of the present invention.

FIG. 2 is an explanatory diagram showing one embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 input device (transmission device) 2 output device (transmission device) 3 operation device (transmission device) 4 management device (transmission device) L bus

Claims (2)

[Claims] 1. A transmission device for transmitting a transmission frame including data of a plurality of channels to a bus including data of a channel previously transmitted, and a transmission frame for receiving a transmission frame flowing through the bus and continuously transmitting data of the same channel. A data transmission device comprising: another transmission device that receives a plurality of times. 2. The data transmission device according to claim 1, wherein said another transmission device is adopted when a plurality of received data of the same channel are the same.