Thư viện lập trình ICP DAS DeviceNet Master Library

ICP DAS DeviceNet Master Library (DLL functions) for Windows 98/ME/NT/2000/XP provides users to establish DeviceNet network rapidly by Master/Slave connection model. The users can develop various DeviceNet application softwares via this library. The DeviceNet master library is for PCI CAN interface card, which are PISO-CAN200/400, PISO-CAN200/400U, PCM-CAN200/200P and PISO-CAN200E. Applying the library, users don’t need to take care of the detail of the DeviceNet protocol.
The library implements the DeviceNet protocol automatically. It can reduce the complexity of user's DeviceNet master software. The library mainly implements the DeviceNet protocol with the PISO-CAN 200/400, PISO-CAN 200U/400U, PCM-CAN200/200P or PISO-CAN200E. It can help users to establish the connection with DeviceNet slave devices easily. The general application architecture is demonstrated as following figure.
The library only provides the DeviceNet Master mechanism to communicate with slave devices by the Predefined Master/Slave Connection Set, which can be clarify as two forms: One is the Explicit Message and others are I/O Messages.

Applications

• Industrial Machinery
• Building Automation
• Medical
• Maritime
• Restaurant Appliances
• Laboratory Equipment & Research

Library Layer

The user’s DeviceNet application programs can be developed by the following designated tools: VB, Delphi and Borland C++ Builder…etc. In these tools, the application program can call the PISOCANDNM.DLL driver to implement DeviceNet network application.

Library Features

• Driver supported for Windows 98/ME/NT/2000/XP
• Programmable Master MAC ID.
• Programmable transfer-rate 125K, 250K, 500K
• Each port support maximum nodes up to 64
• Support Group 2 Only Client functions
• Support UCMM functions
• The maximum Fragment number is (Input/Output) up to 64
• Support I/O Operation Mode: Poll, Bit-Strobe and Change Of State/Cyclic
• Support Auto-Scan slave device function
• Support on-line adding and removing devices
• Support Auto-Reconnect when the connection is broken

Note that before communicating I/O data with DeviceNet slave devices, the Master device must connect to slave devices by explicit message connection to define the connection object. Here, we only provide one explicit message connection and four I/O connections as depicted in the figure as shown below.

The DeviceNet communication protocol is based on the concept of connections method. Master should create connections with slave devices based on the command of exchanging information and I/O data. To establish master control mechanism, there are only four main steps to be followed. Figure 1.3-3 demonstrates the basic process for the DeviceNet master communication. The every step function is described in below:

1. Add device into network
   You should provide the slave device’s MAC ID to add into network.
2. Configure connection
   You can check the slave device’s I/O connection type and the I/O data length. When configuring the I/O connection, you should provide these parameters.
3. Establish connection
   After configuring connections, users can start communicating with slave devices.
4. Access I/O data
   After communicating with slave devices, you can access the I/O data with corresponding read/write function.

After establishing the explicit connection, the connection path is then used to exchange the general information from one node to the others. And then users can create the I/O connections in the next step. Once I/O connections have been created, I/O data may be exchanged among devices in the DeviceNet network according to master device demand. Therefore, the master device can access I/O data of the slave devices by one of the four I/O connection methods. The library is not only easy to use but also providing a lot of the DeviceNet Master functions to retrieve and deliver the slave’s I/O data.

The DeviceNet Master X-Server is a high-performance DeviceNet master engine. The DeviceNet master engine implements DeviceNet protocol automatically when the engine is active. The engine always listens to the bus and receives the message at the same time. It works as shown in the following figure.

The DeviceNet Master X-Server has a “ScanList” to store the remote slave devices information. After power off, the information still exists in the configuration file. When the users turn on the PC next time, the “ScanList” will be loaded from the configuration file. The users can easily use the DLL functions to configure it, including adding devices or removing devices. It works as shown in the following figure.