CAN Controller Validation

Requirement

Functional validation of the CAN controller of an ARM cored Integrated GPS chip

System Overview

Our Client’s decision to outsource CAN validation was based on the premise that 'the more testing you do; the better'. With finite resources and specialized knowledge in the GPS domain, the client could at best conduct only high level testing for this Automotive protocol. Embitel’s expertise in the Embedded Automotive domain and our reputation for providing high quality validation services made Embitel the choice of Vendor.
To carry out the functional validation of the CAN controller, Embitel proposed a comprehensive test plan with more than 100 unique test cases of the following:

• Initialization of controller
• Baud rate verifications
• Various operating modes of the controller
• Error counters
• Transmission / Reception of CAN messages
• Interrupt handling of CAN controller
• Microcontroller specific extended features

Implementation

The CAN network simulation was done using SamDia and HS+ interfaces. Test stubs for activating various features of the controller were prepared using uVision IDE.

After four weeks of intense testing, we discovered some serious issues in Baud rate synchronization and Sleep mode. We also found a few issues in the test mode of the CAN controller. We investigated the problem further and narrowed it down to the CAN IP (our client had bought the CAN IP from another vendor). Though this IP was expected to perform in all the scenarios, it however had certain limitations.

Embitel was able to verify the IP and identify its limitations. This input from Embitel was indeed timely and it helped the client fix these defects well before the release date. It was an excellent learning for the Embitel team and also a very good reassurance for the client about Embitel’s capabilities in the field of testing and validation.

Tools

• SamDia and HS+ interface for simulating CAN nodes
• uVision IDE for creating test stubs