JPH03182198A - Data transmission system - Google Patents

Abstract

PURPOSE:To accelerate the speed of an initial setting at the start of a system and to make the parameter maintenance concerning the analog input of each slave station by storing an initial setting data including a parameter concerning the analog input of each slave station to the non-volatile memory of the main station. CONSTITUTION:A non-volative memory 14 of a semiconductor memory storing the initial set data of respective slave stations 2a-2n including the parameter concerning the analog input of the respective slave stations 2a-2b, is provided on a main station 1. Also, a CPU 12 to execute the control of this non-volatile memory 4 and a transmission control part 11 is provided. And, this initial setting means is realized by the CPU 12 and a memory part. Thus, the necessity to input the parameter concerning the analog input of slave stations 2a-2n is eliminated and the maintenance is facilitated and the time necessary for the initial setting to the respective slave stations at the start of the system can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data transmission system that can efficiently set initial setting data for each slave station that handles analog input.

[Conventional technology]

FIG. 5 is a block diagram showing a conventional data transmission system disclosed in, for example, Japanese Patent Publication No. 1-29464. In FIG. 5, 1a is a central monitoring device (main station) that collects field data from each slave station 21a, . . . , 11 is a transmission control unit that exchanges data with the transmission path 4, 12a is a control unit,
13 is a memory section for storing data; 16 is an input section for receiving and taking various information from the outside; 31 is a transmission control section of the slave station 21a that exchanges data with the transmission path 4; 32a is a control section of the slave station 21a; A memory section 35 of the slave station 21a is an input/output section that receives field data from the outside. Also, the 6th
The figure is a timing diagram showing how data is transmitted.

Next, the operation will be explained. First, at the master station 1a, each slave station 2
1a, . . . and transmits the operating conditions to each slave station 21a, . . . (FIG. 6).

Then, the master station 1a sends a polling signal (POL>) to each slave station 21a, . Field data indicating the status of external equipment (not shown) managed by the main station 1a is sent to the main station 1a using the transmission control unit 31. During operation, if a certain slave station 21a stops, etc., and it becomes necessary to reset the operating conditions, it sends a setting request signal to the master station 1a in response to a polling signal (see Fig. 6).
). The master station 1a then sends the operating conditions to the slave station 21a again.

FIG. 7 shows a conventional data transmission system in more detail. In FIG. 7, 12a is a control unit (hereinafter referred to as CPU), 13 is a memory unit that stores programs and data, 14 is a nonvolatile memory that stores parameters related to the external device 15, 16 is an input unit,
1T is a keyboard. Then, each slave station 21a to 21
nfC>, 32a is the CPU of slave stations 21a to 21n,
33 is a memory section for storing programs and data;
4 is an external device managed by the slave stations 21a to 21n, 35 is an input/output unit that exchanges data with the external device 34, and 36
is a nonvolatile memory that stores parameters for analog input and output. Furthermore, FIG. 8 shows the configuration of the transmission control section 11 in more detail. In FIG. RAM.

114 is a transmission controller that controls transmission; 115 is a driver/receiver for connecting to the transmission line 4; and 116 is a shared memory IJ for exchanging data with the CPU 12a.
, 117 is a bus interface.

Next, the operation of the main station 1a will be explained with reference to the flowchart shown in FIG. At the start of operation, CPU12
a writes initialization data to the shared memory 116. The CPU 111 of the transmission control unit 11 is the bus interface 1
The transmission controller 11 reads this data via the transmission controller 17.
Initial settings are performed (step 5T31). Next, the CPU
12a indicates each slave station 21a~ inputted from the keyboard 1T.
21n operating conditions are written into the shared memory 116. Then, the CPU 111 reads this data and stores it in RAM 1.
13. The data in RAM 113 is then provided to transmission controller 114 . Transmission controller 1
14. It sends the operating conditions to each slave station 21a to 2tn at a predetermined timing (step 5T32). After this,
If there is data to be sent to each of the slave stations 21a to 21n, the data is sent by performing the same operation as when the operating conditions were sent (steps 5T34 and 5T35). If there is no data to be sent, only polling transmission is performed (step 5T36). When data is received from each slave station 21a to 21n (step 5T37), the transmission control unit 11
CPU 111 writes this data to shared memory 116. Then, the CPU 12a uses this shared memory 11
The data is received from 6 (step 5T38). In addition,
When receiving an operating condition setting request signal from any slave station 21a to 2tn (step 5T33), the CPU 12
a obtains the signal via the shared memory 116, writes the operating conditions of the corresponding slave stations 21a to 21n in the shared memory 11s in accordance with the signal, and causes the transmission control unit 11 to transmit it (step 5T39).

FIG. 10 shows a portion of the input/output section 35 of each slave station 21a to 21n that processes analog input.

In FIG. 10, 351 is an operational amplifier that inputs the analog signal output from the external device 34, 352 is an analog scanner that sequentially selects the outputs of the plurality of operational amplifiers 351,
353 is a programmable gain controller (PGC) that amplifies the output of the analog scanner 352.

Note that the amplification factor of the operational amplifier 351 is "1". 35
4 is an A-D converter that converts the output of the PGC 353 into a digital converter; 355a is a control unit for the input/output unit 35; 356
is a shared memory for exchanging data with the CPU 32a,
357 is a bus interface.

Next, the operation of this input/output section 35 will be explained.

Amplification factor and A-D according to each analog input of PGC353
Parameters regarding converter 354 are stored in nonvolatile memory 36 in advance. And CPU
32a, the parameters of this nonvolatile memory 36 are transmitted to the control section 355a of the input/output section 35 via the shared memory 356. The control unit 355a sequentially switches the analog scanner 352 to pass the analog input, sets the gain of the PGC 353 to a predetermined value corresponding to the input, and sets the quantization step of the A-D converter 354. etc.

As a result, the analog input becomes a digital value subjected to predetermined scale conversion, and this digital value is sent to the CPU 32aluO via the shared memory 356.

Then, the CPU 32a sends this digital value to the main station 1a in response to the polling signal from the main station 1a.

[Problem to be solved by the invention]

Since the conventional data transmission system is configured as described above, each slave station 2 is automatically transmitted using the keyboard 17 when starting up the master station 1a, or automatically from an external computer, etc.
There was a problem in that initial setting data for 1a to 21n had to be input, and it took time to start up the system. In addition, since the parameters related to the analog input of the slave stations 21a to 21nK are stored in the non-volatile memory 36, initial input work and modification work for the parameters must be performed at the slave stations 21a to 21n, which are usually not installed in a good environment. However, there was a problem in that these tasks also required a long time.

This invention was made in order to solve the above-mentioned problems, and aims to provide a data transmission system that allows system start-up to be performed more quickly and that allows for easy input and change of parameters related to analog input. shall be.

[Means to solve the problem]

In the data transmission system according to the present invention, each slave station is provided with a parameter setting section that receives parameters related to analog input to be input to each slave station from the master station and sets parameters of the analog input input section using the received parameters. The station is provided with a non-volatile memory for storing initial setting data of each slave station, and an initial setting means for transmitting the initial setting data in the non-volatile memory to each slave station.

[Effect]

The nonvolatile memory of the master station in this invention stores initial setting data including parameters related to the analog input of each slave station, so it speeds up the initial setting of each slave station at system startup, and also Facilitates maintenance of parameters related to input.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, reference numeral 14 denotes a non-volatile memory, which is a semiconductor memory, which stores initial setting data of each slave station 2a to 2n, including parameters related to analog input of each slave station 2a to 2n, and 12 denotes this nonvolatile memory 14 and the transmission control unit 11. This is a CPU that performs control. Note that the initial setting means is realized by a program stored in the CPU 12 and the memory section 13. Other parts are the same as those shown in FIG. 7 with the same reference numerals. Then, in each slave station 2a to 2n,
The nonvolatile memory 36 provided in the conventional slave stations 21a to 21n is not required. 2 shows a detailed configuration of the main station 1, and FIG. 3 is a flowchart showing the operation of the main station 1.

Next, the operation will be explained. Initial setting data for each of the slave stations 2a to 2n, including parameters regarding the analog input of each of the slave stations 2a to 2n, is input to the main station 1 using a terminal device (not shown). Then, it is stored in the nonvolatile memory 14 of the main station 1. When the main station 1 is powered on, the CPU 12 writes its own initial setting data into the shared memory 116, and the CPU 111 of the transmission control unit 11 reads the data and initializes the transmission control unit 11 (step ST, 1
1). Subsequently, in order to allow each slave station 2a to 2n to participate in the system, initial setting data for each slave station 2a to 2n is read from the nonvolatile memory 14 and written to the shared memory 116. Then, the CPU 111 reads the data from the shared memory 116 and sequentially sends it to the transmission path 4 via the transmission controller 114 and driver/receiver 115 (step 5T12). Each slave station 2a to 2n is
It receives the initial setting data addressed to its own station and initializes its own station. In this way, each slave station 2a-2n enters the system.

In the master station 1, if there is data to be transmitted to each of the slave stations 2a to 2n, the CPU 12 writes the transmission data into the shared memory 116. Then, the CPU of the transmission control unit 11
111 temporarily stores the data in RAM 113. When the time comes to access the slave stations 2a to 2n that send the data, the CPU 111 sends the data to the RA.
The data is read from M 113 and sent to the transmission line 4 via the transmission controller 114 button and driver/receiver 115 (steps 5T14 and 5T15).

At that time, if there is no data to be sent, only a polling signal is sent (step 5T16).

When the transmission control unit 31 of the slave stations 2a to 2n receives the transmission data box or polling signal transmitted from the master station 1, the slave stations 2a to 2n transmit the data input from the external device 34 to the master station 1. Send to.

The main station 1 receives the data via the driver/receiver 115 and the transmission controller 114.
Stored at AM 113. Then, C of the transmission control section 11
The PU 111 stores the data in the RAM 113 in the shared memory 1.
Write to 16. CPU 12 reads the data from shared memory 116. In this way, slave stations 2B to 2n
The field data collected is received by the CPU 12 (steps STI 7, 5T18, 5T20).

If a failure occurs in a certain slave station 2a to 2nw, for example, slave station 2a, that slave station 2a will be separated from the system. The CPU 12 learns of this through the transmission control unit 11, performs predetermined trouble handling, and then displays an alarm on the external device 15 (steps 5T13 and 5T22). When the operator recognizes this alarm display and performs the specified confirmation operation,
The CPU 12 instructs the transmission control unit 11 to send a restart command, and the transmission control unit 11 sends the restart command to the transmission line 4 (steps 5T23 and 5T24). The restart command is repeated until the failed slave station 2a sends an initialization request response. Then, when the failure of the slave station 2a is recovered and the slave station 2IL receives the restart command, it sends an initialization request response. Then, the CPU 12 receives this response via the transmission control unit 11, writes the initial setting data of the slave station 2a stored in the nonvolatile memory 14 into the shared memory 116, and causes the transmission control unit 11 to send it ( Step 5T25)
. In this way, by having the slave station 2a re-enter the system under the initiative of the master station 1, the control program in the master station 1 can be simplified, as compared to the conventional case. (44) In the conventional case, since the slave station 2a can send an initialization request response at any time, the master station 1 may receive an initialization request response while transitioning to a failure handling operation.

In this case, depending on when the initialization request is accepted, it is necessary to decide whether to proceed to failure handling operation or to interrupt the transition and perform processing according to the initialization request. The program becomes complicated.

FIG. 4 shows the analog input portion of the input/output section 35 of the slave stations 2a to 2n. Its composition is the 10th
Although it is similar to that shown in the figure, in this case, parameters related to analog input are received by the CPU 32 from the main station 1 during initial setting and stored in the memory section 33.

Then, from this memory section 33, the input/output section 350 control section 3
55.

Furthermore, if it is necessary to change the parameters, press the button on the main station 1 and use the terminal (not shown) to change the non-volatile memory 1.
4, and the CPU 12 sends the rewritten contents of the nonvolatile memory 14 to the shared memory 11 as transmission data.
Write in 6. Then, the CPU 111 of the transmission control unit 11
reads this data and sends it to the transmission line 4. Follower 2
The CPUs 32 of a to 2n receive this data and
It is applied to the control section 355 of the input/output section 35 via the bus interface 357 and the shared memory 356. thus,
This means that the parameters related to analog input have been updated in the slave stations 2a to 2n.

On the other hand, the parameters can also be changed in the slave stations 2a to 2n in the same way as in the conventional case. Press the buttons on slave stations 2a to 2n and connect the terminal (
(not shown), the CPUs 32 of the slave stations 2a to 2n read the changed parameters from the memory section 33 and send them to the master station 1 in the same way as when field data is sent. Send to.

The main station 1 receives this and performs a rewriting process on the nonvolatile memory 14 (step 5T21 in FIG. 3).

In the above embodiment, the initial setting data of each slave station 2a to 2n is stored in the nonvolatile memory, but in consideration of the case where the contents of the cine volatile memory are destroyed due to an unexpected situation, the terminal device The contents may be saved in external auxiliary memory.

In the above embodiment, the initial setting data is input to the main station 1 using the terminal device, but the main station 1 is provided with an IC card interface to save and write the initial setting data on the IC card. If you use the IC card only when you use the IC card, you can easily input and save initial setting data. Then, insert the IC card into the main station 1.
If the IC card is always kept in the IC card, this IC card can also respond to initialization requests from the slave stations 2a to 2n, and the nonvolatile memory 14 becomes unnecessary.

〔Effect of the invention〕

As described above, according to the present invention, in the data transmission system, the slave station is provided with a parameter setting section that receives parameters from the master station and sets the parameters of the analog input input section, and the master station has a This configuration includes a non-volatile memory that stores initial setting data for the device, and an initial setting means that sends initial setting data including parameters related to analog input to each slave station. There is no need to input parameters, which facilitates maintenance, and also has the effect of shortening the time required for initial settings for each slave station when starting up the system.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the central part of a data transmission system according to an embodiment of the present invention, Fig. 2 is a block diagram showing the detailed structure of the transmission control section shown in Fig. 1, and Fig. 3 is an operation of the main station. FIG. 4 is a block diagram showing the input/output section of the slave station, FIG. 5 is a configuration diagram showing a conventional data transmission system, FIG. 6 is a timing diagram showing data transmission, and FIG.
8 is a block diagram showing the configuration of the transmission control section shown in FIG. 7, and FIG. 9 is a flowchart showing the operation of the conventional main station. FIG. 10 is a block diagram showing the input/output section of a conventional slave station. 1 is a main station (central monitoring device), 11 is a transmission control unit, 12 is a CPU, 14 is a non-volatile memory, 2a-2n are slave stations, 32 is a CPU, 34 is an external device, 35 is an input/output unit,
4 is a transmission line. In addition, the same symbols in the figures indicate the same or equivalent parts. Patent Applicant Mitsubishi Electric Corporation Figure 5 Procedural Amendment (Voluntary) Name of the Invention Data Transmission System 3, Relationship with the Amendment Person Case Patent Applicant Address 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Name (601) Mitsubishi Electric Corporation Representative Moriya Shiki

Claims (1)

[Claims] In a data transmission system comprising a plurality of slave stations connected to a transmission path, and a centralized monitoring device having a transmission control unit that exchanges data with each of the slave stations via the transmission path, A parameter setting section is provided which receives parameters related to analog input input from the central monitoring device and sets parameters of the input section of the analog input according to the received parameters, and the central monitoring device is provided with initial setting data of each of the slave stations. A data transmission system comprising: a non-volatile memory for storing a non-volatile memory; and initial setting means for transmitting to each slave station initial setting data containing parameters related to analog inputs of each slave station in the non-volatile memory.