Today:

   News & Events

      News

      Events

      Special Offer

      e-NewsLetter

      Press Releases

   Related Links
>visionsystems.de/News & Events / News / news10012008.htm

CAN BUS adapters in ruggedized metal case

Easy installation, simple connection of a PC to CAN BUS networks

 
 
 
Sample application:
Our products:
NET-CAN on TCP/IP

USB-CAN on USB 2.0
SER-CAN on RS232

 

The Controller Area Network (CAN or CAN-Bus) has been invented for use in vehicles (cars, trucks) to reduce the complexity of the cabling systems and to allow the control of different sensors and devices. Because of its reliability against noise and transmission errors the CAN-Bus is also used as an industrial "Fieldbus". Today CAN-Bus is mainly used to control factory automation for many different controlling and data acquisition applications.

CAN-Bus is a broadcast bus with differential serial data transmission, where the bits are
being send in NRZ coded frames. The frames consist of an ID to identify the sender type and up to 8 data bytes, the frames are sensed from all CAN-bus nodes. A CAN network can be configured to work with two different frame formats: the standard frame format has an 11Bits ID (CAN 2.0A) whereas the extended frame format uses a 29Bits ID (CAN 2.0B). CAN-Bus features an automatic 'arbitration free' transmission. A CAN message that is transmitted with highest priority will 'win' the arbitration, and the node transmitting the lower priority message will sense this, back off and wait.

Using the VScom CAN adapters a PC can be connected to the CAN Network in a simple manner: over USB, over a serial port or over Ethernet. All VScom CAN adapters support both CAN 2.0A and CAN 2.0B frame format to fulfil the task of controlling and monitoring. The PC can in the same time additionally
be used to log the data and status of the CAN-bus, without interfering with the control application.

 

The CAN adapters also support CANFestival, an Open Source CANopen Framework. CANopen is a CAN-based higher layer protocol that is used in various application fields, such as medical equipment, offroad vehicles, maritime electronics, railway applications or building automation. CANopen unburdens the developer from dealing with CAN-specific details such as bit-timing and implementation-specific functions. It provides standardized communication objects for real-time data, configuration data as well as network management data.
CANHacker, a tool for analyzing and transmitting frames on the CAN BUS, is included in the product package.

 

The NET-CAN adapters are connected to a PC via Fast Ethernet and support data speeds up to up to 1MBit/s over the CAN Network. The drivers for Windows operating systems install a virtual serial port (Com Port). This COM Port is then used by the software to transfer data and commands to the CAN-bus. Hardware-based automatic flow control of the COM Port ensures the reliable data transmission, i.e. no data losses, to/from CAN bus.
Additionally to the Driver Mode with virtual serial ports the NET-CAN may operate via Raw TCP. Since the flow control is performed inside the NET-CAN, even in this mode the transmission is reliable. Raw TCP may be used by any operating system, not only Windows.

Because the drivers basically emulate a serial COM port, the users may use a terminal program for data transmission and control. The binary data of CAN bus are converted to an ASCII-format, they are sent in this form. The same ASCII-format is available on Raw TCP, so instead of a serial terminal program an application like Telnet performs the same tasks for users. This modus may be used manually, to simply test the equipment in the installation phase. Also dedicated customer applications can use the terminal mode. However this is an effort, which is not necessary to be done. Instead the customer applications can use the supplied CAN frame library (a DLL in Windows), which automatically packs the application data and commands into the CAN bus frame data format for send, receive and control/status commands. Using the CAN frame library the user can focus on his real application, and don't care about the frame data formats. The CAN Frame library is developed to be compatible with future VScom CAN products.

 

The USB-CAN adapters are connected to a PC via USB 2.0 and support data speeds up to up to 1MBit/s over the CAN Network. Also USB 1.1 with the Full Speed data rate of 12Mbit/s is sufficient to operate this device. Therefore even older computers are suitable for CAN operation.

The drivers for Windows operating systems install a virtual serial port (Com Port).
This COM Port is used in the same way as the virtual serial port with NET-CAN, providing all the same options.
Also under Linux OS drivers emulate a serial port, with secure flow control as well.

The power supply of USB-CAN is provided via the USB port, which results in minimum cabling. The low power consumption is an additional advantage.

 

The SER-CAN adapter is similar with the USB-CAN adapter, but it is connected directly to an RS232 serial port of any computer. The SER-CAN adapter has the same specifications concerning CAN bus interface and operates the serial port in the same way as USB-CAN. The SER-CAN adapter uses the same CAN frame library as interface for native CAN frame format. The RS232 interface limits the maximum data speed on the serial port side, but the adapter can be configured to filter frames based on certain information, so it only accepts the matching data. This feature, optionally combined with suitable higher level protocols, can significantly reduce the required data throughput. Further the SER-CAN uses RTS/CTS flow control to guarantee the error free data transmission.

The SER-CAN is powered by an 5V DC external power adapter. A suitable wall-plug adapter is part of the packaging.



All adapters are available at a very attractive price.


 

 
Related products: USB-CAN and SER-CAN
USB-CAN | SER-CAN | NET-CAN |
 
Back to the News Page.
 

 

All trademarks and brands are property of their rightful owners.
Copyright © 2005-2019, VS Vision Systems GmbH. All Rights Reserved.