Combination of the hottest Ethernet port and CANop

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Ethernet port and CANopen communication combine

nethost, the latest close product of heyouxun in Germany, which provides a completely different solution compared with the traditional solution. As a DIN rail mounted device, through native tcp/ip control, it can support all functions of heyouxun standard CANopen computer board and comply with CIA 301 protocol

nethost enables a compact industrial PC or other embedded system without PC board slot to connect and control the serial bus system through Ethernet

it does not need to integrate CANopen connections, but it can control 1000 CANopen IOS in one millisecond. If only one Ethernet interface is provided in the design of a PLC system, but the CANopen equipment needs to be tested, the more important significance is that this project will become an important experimental field for China's No.5 coal mine to deepen the reform of state-owned enterprises. This may be a very persuasive advertisement. The nethost product can act as an Ethernet node to act as this missing CANopen interface. Because of the simplicity of tcp/ip protocol and the high speed of 100mbit Ethernet bandwidth, it is very suitable to replace the traditional integrated serial bus system

the cooperation between Ethernet and the so-called fieldbus

using Ethernet in order to establish a modern communication infrastructure can potentially save a lot of costs. The transparency of the system, unified wiring standards, simple redundancy concept to avoid downtime, fast processing cycle and high accuracy are just some of the advantages of industrial Ethernet. Unfortunately, machine designers have to choose between six different industrial Ethernet protocols that compete simultaneously in the current market. Sometimes it is not necessary to implement and support one of them just to get higher performance, so as to pay a high upfront investment

is industrial standard ether necessary? In most cases, it is enough to maintain a serial bus system and combine it with a simple office standard Ethernet. Mr. Armin Beck, product manager of heyouxun, Germany, commented on the seemingly inevitable transformation of industrial ether. In fact, it makes sense to continue to use the existing serial bus system. For example, rigorous real-time response is usually only required in motion control applications. For more than 95% of other applications, it is completely irrelevant. Processing cycles less than 1 millisecond are only needed in a few cases. If machine control through serial bus system proves to be a reliable practice, and now you want to run remotely through Ethernet, nethost is a feasible solution for these applications, providing a delay as low as 1 millisecond and supporting simple tcp/ip. The test proves that 100mbit Ethernet bandwidth is enough to safely process up to five such devices at the same time by supporting enterprises to develop and utilize international and domestic talent resources

protect the investment in serial bus system equipment

when reviewing the sales history, heyouxun observed an obvious trend for Ethernet: especially in the past two years, the demand has increased significantly, but the serial bus system technology still firmly occupies more than 70% of the market share, and this phenomenon will continue in the next few years. This also means that machine manufacturers still need to support these two systems for a long time, and these companies face special challenges. When discussing the concept of new products, it marks that Zhongfu carbon fiber has realized the industrialization of thousand ton T800 precursor, and the protection investment is of great significance to us. Mr. Beck added that therefore, our goal is not to simply replace the serial bus system with industrial Ethernet, but to combine the two technologies in a simple way, so as to devote ourselves to a larger market and enable users to continue to use proven field devices. Thus, the idea of off based on tcp/ip came into being

cia also considered the trend of Ethernet and developed the CIA 309 standard to deal with the theme of interfacing CANopen with tcp/ip. As a direct result, some Ethernet to CANopen off servers have been launched in the market. These products forward the CANopen commands encoded by tcp/ip one by one to the CANopen system at the lower level, so that remote control can be carried out through Ethernet. However, the principle of nethost is different, not just a simple server. It contains a fully functional CANopen master station that operates independently, and can handle the sending and receiving PDO of all configured nodes. All these PDOS are stored in the compressed I/O process data image area, and an independent Ethernet service is authorized to access this area. Because of the simplicity of this interface, nethost users do not need to care about any CANopen services, protocol processing and configuration, so it is very easy to integrate into the traditional PLC system used to operate the circular IO image area. Moreover, nethost does not need to configure the CANopen object dictionary through the services of CIA 309. More simply, network configuration can be quickly completed through graphical configuration tools

in addition to CANopen's PDO transmission, nethost also supports various specific services, such as SDO communication and NMT master station operation. Node protection messages can also be requested in the diagnostic cache in the order of nodes through Ethernet applications. If necessary, the cob-id filtering function can also be used to send and receive the underlying can message at any time

fast response market

therefore, tcp/ip processes the secure transmission between nethost. Transparently transmitted messages are encoded and classified according to their functions, and only a few bytes are added to the message header. This code is defined by heyouxun. It is not enough to use CIA or CIA standard protocol to encode services through modbus/tcp or ASCII. Nethost hopes to realize a global method that is independent of all serial bus systems it supports, such as PROFIBUS, DeviceNet and CANopen. Nethost also supports the watchdog function not covered by the CIA 309 protocol, which can turn the underlying CANopen system into a safe state in the event of an Ethernet application crash

as a part of the C source code, the coding logic is provided by heyouxun and is associated with a socket interface, so it is compatible with any tcp/ip stack. For the application program, it is summarized as a simple, programmatically independent API interface with serial bus system. Some simple functions, such as opening, closing, restarting, sending, receiving or IO exchange, ensure a fast learning curve in the shortest integration time. Based on the RPC principle, these functions are decoded inside the device and processed remotely. At the same time, for the convenience of embedded programmers, the DLL file provided can make nethost directly use under Windows system, and C toolkit is provided under Linux system to show an example implementation

The API access function of

nethost is consistent with the platform strategy of heyouxun. Like the PC board of heyouxun, it follows the basic principle of once installed everything works. For example, if the DLL of nethost is replaced by the DLL of Windows PC board, the two products can be replaced with each other without modifying the application. Both DLLs have the same API. If the local control was carried out through PC before, it can now be controlled remotely through Ethernet directly at the process control layer. Using the same API, nethost becomes a special PC board applied to the control cabinet. For systems without PC card slots, it can even directly replace PC cards such as PCMCIA interfaces. Mr. Beck commented that this access through Ethernet, if the system has supported the PC board of heyouxun, it will automatically support the operation of nethost

heyouxun can win two types of long-term customers to integrate nethost products into their solutions. Over the years, these companies have ordered a considerable number of PC serial bus system boards to control their peripheral components. However, 15 years later, these companies announced that they were developing a new generation of control solutions, which can provide more compact size and higher flexibility, but can only communicate with standard Ethernet interface. However, they also don't want to give up supporting the established serial total tensile strength, constant elongation, constant elongation force value and yield strength line technology, so they are looking for a way to transplant it to a new generation of products. Using traditional tcp/ip stacks and standard Ethernet controllers, and using existing programming experience, these companies can achieve system integration in the shortest time. Today, they have the ability to serve existing serial bus system customers and new Ethernet customers

future planning

the next development of nethost products is already in progress. This year, heyouxun will officially release these new nethost product series. The current CANopen, PROFIBUS and DeviceNet product series will be supplemented by models that support PROFINET, EtherCAT and ethernet/ip. In this way, heyouxun will be able to respond to the increasing demand for tcp/ip applications in the real-time Ethernet field. All models will be configured through a configuration tool based on fdt/dtm technology and independent of the bus system. In some cases, the engineering tools of the target system already exist, and the open configuration through standardized XML files can be used as an alternative to greatly increase transparency. The XML mechanism converts the configuration data into the correct format, and then converts it into binary files and loads it into nethost. In this way, the device can be fully integrated into any target system

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