CN103676763A - Method for achieving communication with Siemens S5 PLC based on UNIX platform and LINUX platform - Google Patents

Abstract

The invention discloses a method for realizing communication with Siemens S5PLC based on UNIX and LINUX platforms, through initialization, initializing original sockets, generating sockets, establishing connections, requesting data, and disconnecting processes. The present invention can replace The original upper computer platform software has no additional requirements for the hardware system, and UNIX/LINUX is an open source operating system with low cost, which reduces the cost of hardware and software, and further improves the security and reliability of the system.

Description

Implementation method of communication with Siemens S5 PLC based on UNIX and LINUX platforms

technical field

The invention relates to a method for realizing communication with Siemens S5PLC, belonging to the technical field of communication. the

Background technique

Siemens SIMATIC S5 series PLC is a programmable controller launched by German Siemens in the 1980s. It adopts a compact modular design and has reliable performance. The control system composed of S5PLC as the core is widely used in domestic power plants, steel, chemical and other industrial fields. the

SIMATIC S5PLC generally constitutes a distributed automation system through SINEC H1 network. SINEC H1 network is composed of CP1430 communication module, CP1413 network card, transceiver (Transceiver), coaxial bus cable, terminator, PLC and workstation and other equipment. CP1430 communication module is an interface module for S5PLC to communicate with other devices. SINEC H1 network adopts ISO/OSI reference model, conforms to IEEE802.3 standard, adopts 7-layer structure: physical layer, link layer, network layer, transport layer, session layer, presentation layer, application layer. Layers 1-4 are realized through physical connection and configuration in CP1430, and layers 5-7 are realized through relevant application software. the

Most of the computer monitoring systems using S5PLC in China use PROKON-LSX or FactoryLink host computer system software from Siemens to complete the communication function with S5PLC. Both PROKON-LSX and FactoryLink software have been discontinued and no longer provide corresponding support, while S5PLC is still widely used because of its stability and continuity as an industrial control product. Therefore, it is necessary to provide reliable and stable host computer monitoring software to complete functions such as data exchange, equipment monitoring, and advanced applications. the

The disadvantages of the current computer monitoring system using S5PLC are: (1), PROKON-LSX and FactoryLink software have been discontinued, and no longer provide corresponding support. The computer hardware of the original host computer was seriously aging and could not be replaced, which seriously affected the safe operation of the monitoring system; (2) There was no mature and reliable host computer software based on the UNIX/LINUX platform to complete the communication function. the

After adopting the new upper computer communication software based on UNIX/LINUX platform, the upper computer system can be completely updated to eliminate hidden dangers, and at the same time, it can realize many advanced functions such as dynamic monitoring of equipment, locking of control rights, and statistical analysis of data. the

The UNIX operating system is a powerful multi-user and multi-tasking operating system that supports multiple processor architectures. It is a time-sharing operating system and was first developed at AT&T Bell Labs in 1969. The Linux operating system is a clone system of the UNIX operating system. It is a free-to-use and freely disseminated Unix-like operating system. It is a multi-user, multi-tasking, multi-threading and multi-CPU operating system based on POSIX and UNIX. It can run major UNIX utility software, application programs and network protocols. It supports 32-bit and 64-bit hardware. Linux inherits Unix's network-centric design idea and is a multi-user network operating system with stable performance. The present invention carries out program development based on Redhat Linux system, and transplants in other UNIX/LINUX operating systems. the

Contents of the invention

The technical problem to be solved by the present invention is: to realize the communication with the S5PLC by using the upper computer on the UNIX/LINUX platform, and possess the communication function of 802.3 protocol. the

For solving the problems of the technologies described above, the present invention provides a kind of realization method based on UNIX and LINUX platform and completes communication with Siemens S5PLC, it is characterized in that, may further comprise the steps:

1) In the UNIX/LINUX system, create a socket socket with address family AF_INET and type SOCK_STREAM;

2) Use the device-driven I/O channel management function ioctl in the UNIX/LINUX system to obtain the MAC address corresponding to the communication network card of the upper computer, which occupies 6 bytes in total. The MAC address is used as the source address (Source MAC Address), and The MAC address corresponding to the CP1430 communication module of S5PLC is used as the destination address (Destination MAC Address). the

3) Then initialize the sll_family, sll_protocol, sll_ifindex, sll_hatype, sll_pkttype, sll_halen, source address, destination address and other parameters in the socket, and use the parameters to perform SOCKET connection. The connection process is completed using the SOCK_RAW parameter to receive the protocol including IEEE802.3 All underlying information including SOCKET will return the generated SOCKET descriptor after the SOCKET is established successfully, and the subsequent steps will be completed on the basis of the SOCKET descriptor; 

4) Establish a connection: send a request frame (Connect Request, function code 0xe1), PLC replies with an acknowledgment request frame (Connect Confirm, function code 0xd1), and then sends an acknowledgment frame (Acknowledge, function code 0x60). After these three processes, the communication is established and activate;

5) Request data: read PLC data, send a data frame (Data, function code 0xf0), PLC first replies to the data frame with an acknowledgment frame (Acknowledge, function code 0x60) to represent that it has received the data frame, and then sends a data frame ( Data, function code 0xf0) to reply the data in the PLC, after receiving the data frame replied by the PLC, send another confirmation frame (Acknowledge, function code 0x60) to reply and confirm, at this time, the data request process is completed;

6) Disconnect: Send a request frame (Disconnect Request, function code 0x80), PLC replies with a confirmation request frame (Disconnect Confirm, function code 0xc0), and then sends a confirmation frame (Acknowledge, function code 0x60), the communication connection is disconnected. the

Beneficial effects achieved by the present invention: the present invention solves the problem that Siemens SIMATIC S5PLC and UNIX/LINUX host computer system complete communication through IEEE802.3 protocol, eliminates the defect that S5PLC can only communicate with Windows platform host computer system, and reduces The investment in hardware and software improves the safety and reliability of communication between PLC and host computer system. the

Detailed ways

Since the IEEE802.3 protocol is not a TCP protocol, and an early MAC address-based underlying protocol, the MAC address is used instead of the IP address. Therefore, the present invention completes the connection through the RAW Ethernet communication mode. the

First create a socket with address family AF_INET and type SOCK_STREAM. the

Then use the IO channel management function of ioctl to obtain the MAC address corresponding to the upper computer communication network card, which occupies 6 bytes in total. The MAC address is used as the source address (Source MAC Address), and the MAC address corresponding to the CP1430 communication module of S5PLC is used as Destination MAC Address. The Ethernet data frame format of IEEE802.3 is generally shown in Table 1:

Table 1:

Afterwards, initialize parameters such as sll_family, sll_protocol, sll_ifindex, sll_hatype, sll_pkttype, sll_halen, source address, and destination address in the socket, and use these parameters for SOCKET connection. The connection must be completed using the SOCK_RAW parameter in order to receive All underlying information including the 802.3 protocol. After the SOCKET is successfully established, the generated SOCKET will be returned, and all subsequent operations will be completed on the basis of this SOCKET. the

Set up connection: at first software of the present invention sends request frame (Connect Request, function code 0xe1), PLC can reply confirmation request frame (Connect Confirm, function code 0xd1), software sends confirmation frame (Acknowledge, function code 0x60) afterwards again, this After three procedures, the communication is established and activated. the

Request data: After that, when the software reads PLC data, it will send a data frame (Data, function code 0xf0), and the PLC will reply to the data frame with an acknowledgment frame (Acknowledge, function code 0x60) to indicate that it has received the data frame, and then Send another data frame (Data, function code 0xf0) to reply the data in the PLC. After the software receives the data frame replied by the PLC, it needs to send another confirmation frame (Acknowledge, function code 0x60) for confirmation. At this point, a data request process is completed. the

Disconnect: at first the software of the present invention sends a request frame (Disconnect Request, function code 0x80), and the PLC will reply a confirmation request frame (Disconnect Confirm, function code 0xc0), and then the software sends an confirmation frame (Acknowledge, function code 0x60), The communication connection is broken. the

Above the process of the present invention and PLC communication has been set forth, wherein data frame (Data) has included the SINEC H1 agreement of S5PLC communication, and its format of reading PLC data frame is as shown in table 2:

Table 2:

This allows all valid data to be received correctly and completely. The data writing format is similar to this. the

The present invention is developed on the basis of UNIX/LINUX platform and Siemens S5PLC communication software; Simultaneously, the software of the present invention passes a series of complete series such as initializing, initializing original socket, generating socket, establishing connection, requesting data, disconnecting, etc. All processes are required to be supported by independent program source codes. The present invention can completely replace the original upper computer platform software, and has no additional requirements on the hardware system, and UNIX/LINUX is an open source operating system, with low cost, reduces the cost of hardware and software, and further improves the security and reliability of the system sex. Transplanting the existing software that can communicate with the Siemens S5PLC based on the Windows system to the UNIX/LINUX platform can also accomplish the purpose of the present invention. the

IEEE: Institute of Electrical and Electronics Engineers (English: Institute of Electrical and Electronics Engineers, referred to as IEEE) is an international association of electronic technology and electronic engineers established on January 1, 1963, and is also one of the largest professional technical organizations in the world One, it has 360,000 members from 175 countries. In addition to its headquarters in New York City, the United States, it also has branches in more than 150 countries around the world, and there are 35 professional societies and 2 federations. It publishes a variety of magazines, journals, and books every year, and holds at least 300 professional conferences. The current standards defined by the IEEE in the industry have a great impact. the

PLC: Programmable Logic Controller (Programmable Logic Controller, referred to as PLC), a digital electronic device with a microprocessor, a digital logic controller for automatic control, which can load control instructions into memory for storage and execution at any time. The programmable controller is composed of internal CPU, instruction and data memory, input and output unit, power supply module, digital simulation and other units. PLC is widely used in the current industrial control field. Before the emergence of programmable logic controllers, it was generally necessary to use hundreds of relays and counters to form an automation system with the same function, but now, programmed simple programmable logic controller modules have basically replaced these large device. The system program of the programmable logic controller is generally initialized before leaving the factory, and the user can edit the corresponding user program according to his own needs to meet different automatic production requirements. A PLC can receive (input) and send (output) various types of electrical or electronic signals, and use them to control or supervise almost all kinds of mechanical and electrical systems. the

The above has disclosed the present invention with preferred embodiments, but it is not intended to limit the present invention, and all technical solutions obtained by adopting equivalent replacement or equivalent transformation methods fall within the protection scope of the present invention. the

Claims (1)

1. based on UNIX and LINUX platform, complete the implementation method with Siemens S5PLC communication, it is characterized in that, comprise the following steps:

1), in UNIX/LINUX system, by address family, be that AF_INET, type are that SOCK_STREAM creates socket socket;

2) with UNIX/LINUX devices in system, drive I/O channel management function ioctl to obtain the corresponding MAC Address of upper machine communication network interface card, account for altogether 6 bytes, described MAC Address is as source address (Source MAC Address), and MAC Address corresponding to the CP1430 communication module of S5PLC is as destination address (Destination MAC Address).

3) again by parameter initializations such as the sll_family in socket, sll_protocol, sll_ifindex, sll_hatype, sll_pkttype, sll_halen, source address, destination addresses, and operation parameter is carried out SOCKET connection, connection procedure is used SOCK_RAW parameter to complete, to receive all bottom-up informations that comprise IEEE802.3 agreement, after SOCKET is successfully established, will return to the SOCKET descriptor of generation, subsequent step completes on described SOCKET descriptor basis;

4) connect: send request frame Connect Request, function code 0xe1, PLC replys and confirms claim frame Connect Confirm, function code 0xd1, then send acknowledgement frame Acknowledge, and function code 0x60, after this three process, communication is set up and is activated;

5) request msg: read plc data, send out Frame Data, function code 0xf0, PLC first replys acknowledgement frame Acknowledge to Frame, and function code 0x60, represents that PLC has received Frame, send out again an envelope Frame Data, function code 0xf0, replys the data in PLC, receives after the Frame of PLC reply, to send out again an envelope acknowledgement frame Acknowledge, function code 0x60, is replied confirmation, and now the request process of a secondary data completes;

6) disconnect: send out claim frame Disconnect Request, function code 0x80, PLC replys and confirms claim frame Disconnect Confirm, function code 0xc0, then send out acknowledgement frame Acknowledge, and function code 0x60, communication connects i.e. disconnection.