The market's demand for energy-saving, safe, and intelligent vehicles is increasing, as is the request for integrating ever more electronic products in the car. CAN (Controller Area Network) and its upgrade CAN FD (CAN with Flexible Data-Rate) are widely used communication protocols for in-vehicle network systems. These set up the main framework to communicate with the car's electronic control unit.

The operation of various electronic control systems in the EV is critical to the safety of the entire vehicle. Therefore, how to arrange a complete test plan and verify the components function according to the design specifications and regulatory requirements is a very important topic, among which CAN/CAN FD communication control plays a crucial role.

Chroma's 8000 EV test solutions realize CAN/CAN FD data reading and writing. Users can set up test scripts according to the test plan content, as to simulate and test the CAN/CAN FD signal transmission and reception behavior of the vehicle's key components (such as OBC, DC/DC, BMS, EVSE, et cetera). For CAN/CAN FD data analysis, compared to the previous tedious steps of data interpretation, the Chroma 8000 EV solutions support DBC file import and offer automatic analysis functions for specific signal data.

Take the OBC test items of a well-known power supply manufacturer in Taiwan for example. More than 400 test commands were required in CAN communication (read + send + data analysis). After Chroma introduced the 8000 test solution, the number of communication commands significantly reduced to less than 100. This has greatly improved efficiency in programming of the test items as well as reduced difficulties in maintenance.

To achieve such faster and easier test planning, the main features of Chroma's CAN communication test on the EV automatic test system include:

• Periodically sends CAN/CAN FD packets
• Transmits Cyclic Redundancy Check (CRC) signals
• Sends live counter signals
• Automatically reads and converts CAN/CAN FD signals raw value into the signal’s physical value (following the format definition in the specified DBC file)
• Applies to GB/T 27930 testing
• Supports ISO 14229 Unified Diagnostic Services (UDS)
• Supports ISO 15765 transmission protocol

▲CAN Communication Architecture