CN115994174A - Method and system for playing back HMI (human machine interface) pictures of production line under Hitachi PLC (programmable logic controller) system - Google Patents

Abstract

The invention relates to a method for replaying an HMI picture of a production line under a Hitachi PLC system, which comprises the steps of calling a compiled dynamic link library humiffline. Dll file by the modified HMI picture, reading data stored in a computer shared file by a compiled player, replaying historical data on the production line through the original HMI picture, and providing visual historical picture display for the production line. The invention has the advantages that: the modified HMI picture is played back to the history data stored in the history database, so that the aim of checking at any time and switching at any time is fulfilled, the space occupied by the data in a computer disk is small, and the picture played back for storing the history for a longer time is realized by using a smaller storage space; the compiled player reads the stored history database file and stores the stored history database file in the shared memory of the computer; the modified HMI picture calls the compiled dynamic link library file and reads the data of the compiled player put into the shared memory, thereby realizing playback history data.

Description

Method and system for playing back HMI (human machine interface) pictures of production line under Hitachi PLC (programmable logic controller) system

Technical Field

The invention relates to the technical field of automatic production line control, in particular to a method and a system for playing back HMI pictures of a production line under a Hitachi PLC system.

Background

Referring to fig. 1, a certain steel mill adopts a hitachi PLC system and an original HIM picture, and an HMI computer at an automation line client is provided with the original HMI picture, and the original HMI picture only displays real-time production data and has no function of playing back history data. The original HMI picture realizes the function of reading real-time data in the hardware address of the Hitachi PLC system by calling the original dynamic link library, and when equipment is stopped, operation accidents are caused by improper operation and quality problems are caused by improper monitoring, the common investigation means is to provide historical curve inquiry or historical operation record of key data for analysis or log inquiry of operation alarm information through the original HMI picture, and production managers cannot capture the whole running process of the equipment.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a method and a system for playing back an HMI picture of a production line under a Hitachi PLC system, the modified HMI picture calls a compiled dynamic link library file, the compiled data of a player put into a shared memory of a computer is read, the original HMI picture is replaced by calling the original dynamic link library to read real-time data in a hardware address of the PLC system, and the function of playing back historical data is realized.

In order to achieve the above purpose, the present invention is realized by the following technical scheme:

a method for replaying the HMI picture of production line under Hitachi PLC system, the modified HMI picture calls the dynamic linking library humoffline. Dll file and reads the data stored in the computer shared file by the compiled player, the historical data on the production line is replayed by the original HMI picture, and visual historical picture display is provided for the production line, the specific method is as follows:

(1) the compiled player reads the stored historical database, reads out the data of a certain historical time node, stores the data in the shared memory of the computer, and switches the historical data of different time nodes through manual skip or a timer arranged on the compiled player;

(2) the compiled dynamic link library humoffline. Dll file comprises an rmery_win_flush method and an rmery_win_flush method, wherein the rmery_win_flush method and the rmery_win_flush method are respectively used for replacing the before-used rmery_win_flush method and the rmery_win method in the dynamic link library humdll. Dll, and the quantity, the parameter sequence, the parameter type and the return value of parameters transmitted in the rmery_win_flush method and the rmery_win_flush method are kept consistent with those of the replaced rmery_win_flush method and the replaced rmery_win_flush method;

(3) the modified HMI picture needs to add a reference to a dynamic link library humoffline. Dll file on the basis of the original HMI picture source code, replace character strings in the original HMI source code in batches, replace the original 'rmemry_win bit' with 'rmemry_win bit' and replace the original 'rmemry_win bit' with 'rmemry_win bit', annotate the source code capable of operating field equipment, and recompile the source code to produce a new HMI picture program.

The rmemry_win_offset method is used for reading the digital data in the shared memory of the computer, and the rmemry_win_offset method is used for reading the digital data in the shared memory of the computer.

The compiled player reads the stored history database file and stores the history database file in the shared memory of the computer, and the method specifically comprises the following steps:

s1, opening a history database file;

s2, opening a shared memory file of the computer;

s3, establishing a mapping relation;

s4, reading one piece of data in the historical database;

s5, writing the data into a shared memory of the computer;

s6, reading the next piece of data in the historical database at intervals by a timer, repeating the processes of S4 and S5, and realizing sequential play of the modified HMI pictures;

s7, stopping the timer, and writing no new data into the shared memory of the computer to realize the pause function of the picture;

s8, shortening the time interval of the timer and realizing quick play;

s9, increasing the time interval of the timer to realize slow play;

s10, reversely reading data in a history database to realize a reverse playing function;

s11, a record pointer of a jump history database is used for realizing the function of fast jumping time progress;

s12, recording pointer values in the collection history database, and realizing collection and quick switching at a certain time point.

The method rmemry_win bit_offine specifically comprises the following steps:

s1, opening a shared memory file of a computer;

s2, establishing a mapping relation;

s3, reading the data stored in the shared memory of the computer currently;

s4, calculating an offset according to an address in a parameter transmitted when the rmemry_winbit_offset is called;

s5, copying 4-bit 16-ary characters from the data read from the shared memory of the computer from the offset +1 addresses;

s6, converting the 4-bit 16-system character into 10-system return.

The method rmemry_win_offine specifically comprises the following steps:

s1, opening a shared memory file of a computer;

s2, establishing a mapping relation;

s3, reading the data stored in the shared memory of the computer currently;

s4, calculating an offset according to an address in a parameter transmitted when the rmemry_win_offset is called;

s5, copying 4-bit 16-ary characters from the data read from the shared memory of the computer from the offset +1 addresses;

s6, converting the 4-bit 16-system character into a 16-bit 2-system character, and taking out corresponding 0 or 1 according to bit data in a 'bit' parameter transmitted when the rmemry_win_offset is called and returning.

The modified HMI picture source code specifically comprises the following steps:

s1, adding a reference to a humoffline. Dll file and a statement of a method in an original HMI picture source code file;

s2, replacing all codes referring to the rmnry_win method in batches in an original HMI picture source code file with the rmnry_win_offset method, namely replacing all 'rmnry_win' character strings with 'rmnry_win_offset' character strings by adopting a batch text replacement method, and keeping the rest codes unchanged;

s3, replacing all codes referring to the rmmery_win bit method in batches in the original HMI picture source code file with the rmmery_win bit_offset method, replacing all 'rmmery_win bit' character strings with 'rmmery_win bit_offset' character strings by adopting a batch text replacement method, and keeping the rest codes unchanged.

S4, all codes related to actions of the operable field device are annotated in the original HMI picture source code file;

s5, recompiling an HMI picture program generated by the source code to realize a playback function;

s6, all original HMI pictures are subjected to the steps of S1-S5, and all the original HMI pictures are modified and recompiled to generate new HMI pictures.

The historical database file is stored in a database of historical data and comprises two data fields, namely a time field and all data of the production line in the time.

The data of the historical time node is the data of the historical study obtained by the selected time node or time period.

Stored in the shared memory of the computer is a long string of data spliced from all production data including a certain historical time node.

The HMI image playback system of the production line under the Hitachi PLC system comprises a PLC system, a data acquisition and storage server and a client HMI computer, wherein the data acquisition and storage server is connected with the PLC system through a port and is used for acquiring data of the PLC system and storing historical database files;

the client-side HMI computer is connected with the data acquisition and storage server through a port and is provided with a compiled player, a modified HMI picture, a compiled dynamic link library and a computer shared memory, wherein the compiled player is used for reading a historical database file of the data acquisition and storage server and storing the historical database file in the computer shared memory, and the modified HMI picture is used for calling the compiled dynamic link library file and reading data of the compiled player in the computer shared memory.

Compared with the prior art, the invention has the beneficial effects that:

1. the modified HMI picture is played back to the history data stored in the history database, so that the aim of checking at any time and switching at any time is fulfilled, the space occupied by the data in a computer disk is small, and the picture played back for storing the history for a longer time is realized by using a smaller storage space;

2. the compiled player reads the stored history database file and stores the stored history database file in the shared memory of the computer;

3. the modified HMI picture calls the compiled dynamic link library file and reads the data of the compiled player in the shared memory of the computer, so as to realize playback history data;

4. the functions of normal speed playing, fast forward, fast play, fast backward, reverse play and collection are realized on the modified HMI picture through the compiled player.

Drawings

Fig. 1 is a schematic diagram of the system configuration of HMI screen playback of the present invention.

Fig. 2 is a flow chart of the first embodiment of the method for reading history data and putting the result into the shared memory.

Fig. 3 is a flowchart of a method for reading numerical data in a shared memory in a dynamic link library according to the second embodiment.

Fig. 4 is a flowchart of a method of reading digital data in shared memory in a dynamic link library according to the third embodiment.

Fig. 5 is an external view of an example of a player programmed in the first embodiment.

Fig. 6 is a schematic diagram of an operation at the time of playback of a screen in the fourth embodiment.

Detailed Description

The present invention will be described in detail below with reference to the drawings of the specification, but it should be noted that the practice of the present invention is not limited to the following embodiments.

The Hitachi PLC system provides a designated address field (4096 addresses) for the original HMI picture, the designated address field is used for displaying data for the original HMI picture, the 4096 addresses are used for displaying information on all production lines, each address stores hexadecimal data, the data of all 4096 addresses are circularly sequentially read and sequentially spliced into a long character string by calling a method rmemry_win in an original dynamic link library humdll provided by the Hitachi PLC system, the long character string is used as data of one historical time node and stored in a historical database, and the time for circularly reading the data of 4096 addresses all takes about 1 millisecond, so that all the data read in the cycle can be regarded as all the data of one historical time node.

Referring to fig. 1, a history database stored in a data collection and storage server is shown in detail in "a system for collecting and viewing production line data under a hitachi PLC system and a use method" disclosed in patent publication No. CN 115032938A, a compiled player reads the stored history database, reads data of a certain historical time node, stores the data in a shared memory of a computer, and stores a long character string data formed by splicing all production data containing the certain historical time node in the shared memory; the historical data is stored in a database, and the database file is stored in an MDB format, so that the method is not limited to the file format storage; the history database comprises two data fields, namely a time field and all data of the production line of the time node, and the data structure is shown in detail in a data structure stored in a production line data acquisition and viewing system under a Hitachi PLC system and a using method disclosed by patent publication No. CN 115032938A.

Dynamic link libraries are computer technology terms, which are the basic technology of Windows operating systems, and they cannot normally run directly, and include functions that can be executed by an executable program to perform a certain task, and only when other modules call functions in the dynamic link library, they can function. The compiled dynamic link library humoffline.dll file comprises an rmery_win_flash method and an rmery_win_flash method, wherein the rmery_win_flash method is used for reading digital data in a shared memory of a computer, and the rmery_win_flash method is used for reading the digital data in the shared memory of the computer; the rmemry_win_flush method and the rmemry_win_flush method are used for replacing the rmemry_win bit method and the rmemry_win method in the dynamic link library humdll. Dll used by the original HMI picture respectively, and the quantity, the parameter sequence, the parameter type and the return value of parameters transmitted in the rmemry_win_flush method and the rmemry_win_flush method are consistent with those of the replaced rmemry_win method and the replaced rmemry_win method. The replacement of the rmemry_win bit method and the rmemry_win method changes the original HMI picture data taking mode, changes the data taking from the PLC hardware into the data taking from the shared memory, and the data in the shared memory is stored by the programmed player reading history data.

The modified HMI picture needs to add a reference to a dynamic link library humoffline. Dll on the basis of the source code of the original HMI picture, replace character strings in the source code of the original HMI picture in batches, replace the original 'rmemry_win bit' with 'rmemry_win bit_offline', replace the original 'rmemry_win bit' with 'rmemry_win bit_fline', annotate the source code capable of operating field equipment, recompile the source code to generate a new HMI picture program, and the appearance display of the original HMI picture is unchanged; and similarly, all original HMI pictures are modified and recompiled to generate new HMI pictures.

The system comprises a Hitachi PLC system lower production line HMI picture playback system, a PLC system, a data acquisition and storage server and a client HMI industrial personal computer, wherein the data acquisition and storage server is connected with the PLC system through a port and is used for acquiring data of the PLC system and storing historical database files; the client-side HMI computer is connected with the data acquisition and storage server through a port and is provided with a compiled player, a modified HMI picture, a compiled dynamic link library and a computer shared memory, wherein the compiled player is used for reading a historical database file of the data acquisition and storage server and storing the historical database file in the computer shared memory, and the modified HMI picture is used for calling the compiled dynamic link library file and reading data of the compiled player in the computer shared memory.

The following examples are given by way of illustration of detailed embodiments and specific procedures based on the technical scheme of the present invention, but the scope of the present invention is not limited to the following examples. The methods used in the examples described below are conventional methods unless otherwise specified.

[ example 1 ]

Referring to fig. 2 and 5, the compiled player reads the history database file and stores it in the shared memory, and specifically includes the following steps:

s1, opening a history database file;

s2, opening the shared memory file;

/>

s3, establishing a mapping relation;

s4, reading one piece of data in the historical database;

self.ADOTable1.First；

s5, writing the data into the shared memory;

StrPCopy (pUserInfoShareMem.data, self.ADOTable1.FieldByName ('data'). AsString);

s6, reading the next piece of data in the historical database at intervals by using a Timer arranged on the compiled player and a control Timer provided by a development tool, and repeating the processes S4 and S5;

self.adoptable 1.Next; the pointer of the/database is turned to the next record

StrPCopy (pUserInfoShareMem.data, self.ADOTable1.FieldByName ('data'). AsString);

s7, stopping the timer, and writing no new data into the shared memory to realize the pause function of the picture;

self.Timer1.Enabled:＝false；

s8, shortening the time interval of the timer and realizing quick play;

self.Timer1.Interval =strtoint (edition 1.text); the interval time assignment of the timer is given, 1000 represents 1 second, and the interval is reduced, so that quick release can be realized;

s9, increasing the time interval of a timer to realize slow play;

self.Timer1.Interval =strtoint (edition 1.text); the interval time assignment of the timer is given, 1000 represents 1 second, and slow release can be realized by increasing the interval;

s10, reversely reading data in the historical database to realize the reverse playing function;

self.ADOTable1.Prior; the pointer of the database is turned to the last record

StrPCopy (pUserInfoShareMem.data, self.ADOTable1.FieldByName ('data'). AsString);

s11, a record pointer of a jump history database is used for realizing the function of fast jumping time progress;

s12, recording pointer values in the collection history database, and achieving collection and rapid switching at a certain time point.

[ example 2 ]

Referring to fig. 3, the method for reading the numerical data in the shared memory in the compiled dynamic link library comprises the following steps:

s1, opening a shared memory file;

s2, establishing a mapping relation;

s3, reading the data stored in the shared memory currently;

s4, calculating offset according to an address transmitted when the rmemry_win_offset is called, wherein the memory address of the PLC hardware is continuous, the data displayed in an HMI picture is stored from a specific starting address, the address is not 0, and the data stored in a database file is stored from 0, so that an offset exists between the two addresses;

s5, copying 4 characters, namely 4-bit 16-system characters, from data read from a shared memory from the offset +1 addresses;

s6, converting the 4-bit 16-system character into a 10-system character and returning the 10-system character.

/>

[ example 3 ]

Referring to fig. 4, the method for reading the numerical data in the shared memory in the compiled dynamic link library comprises the following steps:

s1, opening a shared memory file;

s2, reading the data stored in the shared memory currently;

s3, calculating offset according to an incoming address when the rmery_win_offset is called;

s4, copying 4 characters from the data read from the shared memory from the offset +1 addresses;

s5, converting the 4-bit 16-system character into a 16-bit 2-system character, and taking out corresponding 0 or 1 according to bit data in a 'bit' parameter transmitted when the rmemry_win_offset is called and returning; the "bit" parameter is the number of digits represented in integer numbers from 0 to 15;

[ example 4 ]

Referring to fig. 6, the modified HMI frames including four modified HMI frames and a programmed player are not limited to four pairs, and all modified HMI frames may be switched arbitrarily, and data displayed on the modified HMI frames remains consistent in time. The play function of the modified HMI picture is controlled through buttons on a compiled player, any pair of HMI pictures capable of realizing the play function needs to be modified and recompiled to generate a new executable file on the basis of the original codes, the original HMI picture mainly calls an rmemry_win method and an rmemry_win bit method, and the rmemry_win method is used for reading numerical data, and a certain equipment speed, such as the running speed of a rolling mill, is continuous numerical data; the rmemmy_win bit method is used for reading digital type data 0 or 1, for example, whether a signal exists or not, a proximity switch has a signal which is represented by 1, no signal is represented by 0, and 0 or 1 belongs to the digital type data. Various controls displayed on the modified HMI picture are all called an rmery_win method and an rmery_win bit method to display various state information, and the rmery_win method and the rmery_win bit method are defined and realized in an original dynamic link library humdll file.

Dynamic link libraries are computer technology terms, which are the basic technology of Windows operating systems, and they cannot normally run directly, and include functions that can be executed by an executable program to perform a certain task, and only when other modules call functions in the dynamic link library, they can function. The compiled dynamic link library humoffline.dll file comprises an rmery_win_flash method and an rmery_win_flash method, wherein the rmery_win_flash method is used for reading digital data in a shared memory of a computer, and the rmery_win_flash method is used for reading the digital data in the shared memory of the computer; the rmemry_win_flush method and the rmemry_win_flush method are used for replacing the rmemry_win bit method and the rmemry_win method in the dynamic link library humdll. Dll used by the original HMI picture respectively, and the quantity, the parameter sequence, the parameter type and the return value of parameters transmitted in the rmemry_win_flush method and the rmemry_win_flush method are consistent with those of the replaced rmemry_win method and the replaced rmemry_win method. The replacement of the rmemry_win bit method and the rmemry_win method changes the original HMI picture data taking mode, changes the data taking from the PLC hardware into the data taking from the shared memory, and the data in the shared memory is stored by the programmed player reading history data.

The modified HMI picture source code specifically comprises the following steps:

s1, a new reference to a humoffline. Dll file and a statement of a method are required to be added in an original HMI picture source code file;

the method comprises the steps of adding references to an rmery_win bit method and an rmery_win method in a humoffline.dll in HMI source code, and using the rmery_win bit method and the rmery_win method in the code after adding the references

Public Declare Function rmemry_win_offline Lib"humoffline.dll"_

(ByRefmadr As Integer,_

ByRefIOtypeAs Integer,_

ByRefIOadrAs Integer,_

ByRef word As Integer,_

ByValfmt As String,_

ByRefsystbl As Integer)As String

Public Declare Function rmemry_winBit_offline Lib"humoffline.dll"_

(ByRefmadr As Integer,_

ByRefIOtypeAs Integer,_

ByRefIOadrAs Integer,_

ByRef Bit As Integer,_

ByRefsystbl As Integer)As Integer

S2, replacing all codes referring to the rmnry_win method in batches in an original HMI picture source code file with the rmnry_win_offine method, namely replacing all 'rmnry_win' character strings with 'rmnry_win_offine' character strings by using a batch text replacing method, and finishing the replacement of all 'rmnry_win_fan' character strings, wherein the rest codes are kept unchanged;

original calling method for a control in source code of/(HMI) picture

StringTmp＝rmemry_win(crtiom,N_ADDR,&H117EE,2,"％6d",systbl)

This control in the HMI screen source code that requires modification is now called method

StringTmp＝rmemry_win_offline(crtiom,N_ADDR,&H117EE,2,"％6d",systbl)

S3, replacing all codes referring to the rmemry_win bit method in batches in the original HMI picture source code file by the rmemry_win bit_offset method; the method for replacing the batch text is used, all 'rmery_winbit' character strings are replaced by 'rmery_winbit_offset' character strings, and the rest codes are kept unchanged;

original calling method for a control in source code of/(HMI) picture

If rmemry_winBit(crtiom,N_ADDR,&H1163C,&H5,systbl)＝1Then

This control in the HMI screen source code that requires modification is now called method

If rmemry_winBit_offline(crtiom,N_ADDR,&H1163C,&H5,systbl)＝1Then

S4, all codes related to actions of the operable field device are annotated in the original HMI picture source code file;

the key sentences which can execute the screen clicking action in the' ControlEventMake () source code are annotated, the program demonstration is not affected, the clicking button does not send out an instruction, and the misoperation of equipment during watching and playback is prevented;

s5, recompiling an HMI picture program generated by the source code to realize a playback function;

s6, all original HMI pictures are subjected to the steps of S1-S5, and all the original HMI pictures are modified and recompiled to generate new HMI pictures.

According to the invention, through the fact that the modified HMI picture plays back the history data stored in the history database, the aim of checking at any time and switching at any time is realized, the space occupied by the data in a computer disk is small, and the picture playback of the history stored for a longer time is realized by using a smaller storage space; the compiled player reads the stored history database file and stores the stored history database file in the shared memory of the computer; the modified HMI picture calls the compiled dynamic link library file and reads the data of the compiled player in the shared memory of the computer, so as to realize playback history data; the normal speed play, fast forward, fast play, fast backward, reverse play and collection are realized on the modified HMI picture through the compiled player, and the playback of the historical data is realized.

Claims (10)

1. A method for replaying the HMI picture of the production line under the Hitachi PLC system is characterized in that the modified HMI picture calls the compiled dynamic link library humiffline. Dll file and reads the data stored in the computer shared file by the compiled player, and the historical data on the production line is replayed through the original HMI picture to provide visual historical picture display for the production line, and the method comprises the following steps:

(1) the compiled player reads the stored historical database, reads out the data of a certain historical time node, stores the data in the shared memory of the computer, and switches the historical data of different time nodes through manual skip or a timer arranged on the compiled player;

(2) the compiled dynamic link library humoffline. Dll file comprises an rmery_win_flush method and an rmery_win_flush method, wherein the rmery_win_flush method and the rmery_win_flush method are respectively used for replacing the before-used rmery_win_flush method and the rmery_win method in the dynamic link library humdll. Dll, and the quantity, the parameter sequence, the parameter type and the return value of parameters transmitted in the rmery_win_flush method and the rmery_win_flush method are kept consistent with those of the replaced rmery_win_flush method and the replaced rmery_win_flush method;

(3) the modified HMI picture needs to add a reference to a dynamic link library humoffline. Dll file on the basis of the original HMI picture source code, replace character strings in the original HMI source code in batches, replace the original 'rmemry_win bit' with 'rmemry_win bit' and replace the original 'rmemry_win bit' with 'rmemry_win bit', annotate the source code capable of operating field equipment, and recompile the source code to produce a new HMI picture program.

2. The method for playing back HMI pictures in a production line under a hitachi PLC system according to claim 1, wherein the rmmery_win_bit_offset method is used for reading digital data in a computer shared memory, and the rmmery_win_offset method is used for reading digital data in the computer shared memory.

3. The method for playback of the HMI screen in the production line under the hitachi PLC system according to claim 1, wherein the compiled player reads the stored history database file and stores the history database file in the shared memory of the computer, and specifically comprises the steps of:

s1, opening a history database file;

s2, opening a shared memory file of the computer;

s3, establishing a mapping relation;

s4, reading one piece of data in the historical database;

s5, writing the data into a shared memory of the computer;

s6, reading the next piece of data in the historical database at intervals by a timer, repeating the processes of S4 and S5, and realizing sequential play of the modified HMI pictures;

s7, stopping the timer, and writing no new data into the shared memory of the computer to realize the pause function of the picture;

s8, shortening the time interval of the timer and realizing quick play;

s9, increasing the time interval of the timer to realize slow play;

s10, reversely reading data in a history database to realize a reverse playing function;

s11, a record pointer of a jump history database is used for realizing the function of fast jumping time progress;

s12, recording pointer values in the collection history database, and realizing collection and quick switching at a certain time point.

4. The method for playing back the HMI pictures in the production line under the hitachi PLC system according to claim 1, wherein the method comprises the following steps:

s1, opening a shared memory file of a computer;

s2, establishing a mapping relation;

s3, reading the data stored in the shared memory of the computer currently;

s4, calculating an offset according to an address in a parameter transmitted when the rmemry_winbit_offset is called;

s5, copying 4-bit 16-ary characters from the data read from the shared memory of the computer from the offset +1 addresses;

s6, converting the 4-bit 16-system character into 10-system return.

5. The method for playing back the HMI pictures in the production line under the hitachi PLC system according to claim 1, wherein the method comprises the following steps:

s1, opening a shared memory file of a computer;

s2, establishing a mapping relation;

s3, reading the data stored in the shared memory of the computer currently;

s4, calculating an offset according to an address in a parameter transmitted when the rmemry_win_offset is called;

s5, copying 4-bit 16-ary characters from the data read from the shared memory of the computer from the offset +1 addresses;

s6, converting the 4-bit 16-system character into a 16-bit 2-system character, and taking out corresponding 0 or 1 according to bit data in a 'bit' parameter transmitted when the rmemry_win_offset is called and returning.

6. The method for playback of the HMI screen of the production line under the hitachi PLC system according to claim 1, wherein the modified HMI screen source code specifically comprises the steps of:

s1, adding a reference to a humoffline. Dll file and a statement of a method in an original HMI picture source code file;

s2, replacing all codes referring to the rmnry_win method in batches in an original HMI picture source code file with the rmnry_win_offset method, namely replacing all 'rmnry_win' character strings with 'rmnry_win_offset' character strings by adopting a batch text replacement method, and keeping the rest codes unchanged;

s3, replacing all codes referring to the rmmery_win bit method in batches in the original HMI picture source code file with the rmmery_win bit_offset method, replacing all 'rmmery_win bit' character strings with 'rmmery_win bit_offset' character strings by adopting a batch text replacement method, and keeping the rest codes unchanged.

S4, all codes related to actions of the operable field device are annotated in the original HMI picture source code file;

s5, recompiling an HMI picture program generated by the source code to realize a playback function;

s6, all original HMI pictures are subjected to the steps of S1-S5, and all the original HMI pictures are modified and recompiled to generate new HMI pictures.

7. The method for playing back HMI pictures in a production line under a hitachi PLC system according to claim 1, wherein the history database file is stored in a database of history data, and includes two data fields, which are a time field and all data of the production line in the time, respectively.

8. The method for playback of HMI pictures in a production line under a hitachi PLC system according to claim 1, wherein the historical time node data is data of a historical study obtained for a selected time node or time period.

9. The method for playback of an HMI screen in a product line under a hitachi PLC system according to claim 1, wherein the common memory of the computers stores a long string of data formed by splicing all production data including a certain historical time node.

10. The HMI screen playback system for implementing the method of any one of claims 1 to 9 in the production line under the hitachi PLC system, which is characterized by comprising a PLC system, a data acquisition and storage server, and a client HMI computer, wherein the data acquisition and storage server is connected with the PLC system through a port and is used for acquiring the data of the PLC system and storing a history database file;

the client-side HMI computer is connected with the data acquisition and storage server through a port and is provided with a compiled player, a modified HMI picture, a compiled dynamic link library and a computer shared memory, wherein the compiled player is used for reading a historical database file of the data acquisition and storage server and storing the historical database file in the computer shared memory, and the modified HMI picture is used for calling the compiled dynamic link library file and reading data of the compiled player in the computer shared memory.

Images