Quality of our hardware IXXAT is certified according to ISO 9001:2000. Our goal is to guarantee the high quality of the products that we provide to our customers. Therefore, all IXXAT Interfaces are tested
100 %.
CE certification and CSA approval
The IXXAT PC/CAN interface boards fulfill the currently valid EMC directive 89/336/EEC and are CE-certified in accordance with the following standards (these can vary according to the interface used, see manual):
- EN 61000-6-2 (immunity, industrial interference immunity)
- EN 61000-4-2 (air discharge 8 kV, contact discharge 4 kV)
- EN 61000-4-3 (electromagnetic field compatibility 80 MHz - 1 GHz, 10 V/m)
- EN 61000-4-4 (transient distortion factor, burst, bus line1 kV)
- EN 61000-4-6 (HF current compatibility 150 kHz-80 MHz, 10 V)
- EN 55022 (class B, interference emission, trade and small industrial sector)
In addition, almost all IXXAT PC/CAN interface boards have CSA approval for USA and Canada (equivalent to UL approval).
RoHS and WEEE
On 27th January 2003, binding European directives were agreed upon for the restriction of hazardous substances – these took effect permanently on July 1, 2006.
The main aim of the directive is to restrict substances that are harmful to both the environment and to one’s health.
IXXAT delivers all products in accordance with the RoHS directive and is registered at the EAR foundation in Fürth (ElektroG/WEEE). Because of this, all IXXAT components which are distributed exclusively in the B2B area were registered.
Our registration number at EAR: 29724241
Supported physical CAN bus standards
High Speed bus connection according to ISO 11898-2
All CAN boards are available as standard with an on-board CAN bus interface according to ISO 11898-2 (high-speed). Connection of the CAN hardware to the network is generally made via a Sub-D-9 plug-in connector according to CiA-DS102. Versions with alternative plug-in connectors (e.g. RJ45) can be supplied on request.
Low-speed bus connection (fault-tolerant) according to ISO 11898-3
For some CAN boards, a CAN low-speed bus connection is available either as an option or is integrated and activated by software.
Galvanic isolation
The bus connection of the CAN hardware is available as an option with galvanic isolation. Galvanic isolation is achieved by means of opto couplers or magnet couplers and DC/DC converters on the board, and therefore, does not require an external power supply.
Active and passive CAN interfaces
CAN boards can basically be divided into two groups:
Passive CAN interfaces
These boards require direct access of the PC driver to the CAN controller of the board. The PC must configure and operate the CAN controller.
Active ("intelligent") CAN interfaces
These boards have an independent microcontroller system. In addition to configuration of the CAN controller, the microcontroller can also perform time-critical tasks such as the transmission, reception and filtering of CAN messages, can provide received messages with time-stamps, and, can process higher protocols such as CANopen or DeviceNet.
Today PCs are at least 100 times faster than the microcontrollers used on the CAN boards. Nevertheless, the use of CAN boards with their own microcontrollers makes sense because of the following two consideration:
- CAN controllers have only very limited buffering capacities for received messages. In the worst case, a CAN message is received approx. every 50 µs. Depending on the CAN controller used, only a few or only one message can be buffered. This results in a high real-time requirement of the host PC for the reaction of a CAN message which must always be guaranteed in order to prevent a loss of messages.
- The very short processing time for reading out and passing on a CAN message (copying of approx. 12 bytes) is a contrast to the slow context switch of the PC operating system which is triggered by a CAN message. Despite its excellent processing power, this quickly results in a very high load for the PC.
Especially for non-deterministic operating systems such as Microsoft Windows, these aspects can cause a problem with high transmission rates and/or high levels of data traffic. By using powerful active CAN boards, the load on the PC can be relieved or the time-critical requirements can be reduced. For applications with higher requirements in terms of data traffic and deterministic processing of the CAN messages, the use of active boards is always recommended, since variable factors such as the performance of the PC, the number and type of additionally installed boards and drivers and the number of executed programs (e.g. hard disk accesses) do not guarantee a deterministic access to CAN networks.
Active CAN boards also offer the following additional advantages:
- By pre-filtering CAN messages already on the CAN hardware, only relevant messages are forwarded to the PC. Since messages are no longer filtered by the PC program, the workload of the PC decreases.
- With the VCI, independent cyclic transmission of CAN messages by the microcontroller is supported. CAN messages can be transmitted on CAN networks under real-time conditions independent of the PC.
If, on the other hand, the PC is only used for the configuration of CAN components, for example, which is generally carried out via a small number of CAN messages, the performance of a passive board is completely sufficient.
The active CAN interfaces from IXXAT are equipped with various microcontrollers. The standard CAN interfaces are equipped with an 8-bit microcontroller. For most applications with low to medium average message rates these CAN boards are sufficient.
For applications with higher requirements on the communication process, IXXAT supplies active CAN interfaces with 16-bit microcontrollers. Due to the larger memory and higher execution speed, even two CAN networks with high baudrate and high bus load can be operated and monitored. These boards can also perform the function of a CANopen master/manager for networks with many nodes.
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