I/O modules for the CAN bus

ELTEC Elektronik AG developed interface cards for the communication of safety-critical infrastructure. These interface cards are plugged onto a computer board as mezzanine boards and are controlled via SPI or PCI Express. When integrated in the wireless gateway CyBox GW-P or in the automotive LTE router CyBox RT 2-A, the modules enable the collection of operating and sensor data for condition-based monitoring as well as the safe transmission of status data as well as diagnostic and fault messages in order to ensure preventive maintenance in rail and road traffic at the right time.

The CyBox I/O CAN module realizes an interface to the CANbus (CAN V2.0B). The module is based on the CAN controller MCP 2515 and has two internal buffers for data which are controlled by the controller with a data rate of 1 Mbit/s. The MCP 2515 also provides the implementation of ISO 11898-1 functionality in the hardware. The CAN interface is galvanically isolated up to 1,500 VDC and offers a high interference resistance in widely distributed systems. Daisy chaining can be implemented via separate Sub-D connectors. The host interface is designed as an SPI interface and, thus, offers the necessary speed for any kind of CAN transaction.

In uni-directional read-only mode, any intervention in the controller is prevented by blocking writing to the bus in the hardware. This corruption-free communication ensures that control processes, bus signals or writing operations are not affected. Optionally, this module is also available in a bi-directional version.

Dimensions and interfaces comply with the ELTEC standard for mezzanine modules. Other interfaces such as MVB, etc. are available in the same format. The connection to the base board is made via a 30-pin connector with the corresponding SPI and power supply signals. The modules are designed for the extended temperature range of -40 to +70 °C (+85 °C) and for harsh environmental conditions.

ELTEC also offers a complete evaluation kit based on the CyBox RT 2-A automotive wireless router. In addition to the router, the kit includes the CAN module and all necessary accessories such as antennas, adapters, cables, and power supply.