Today’s vehicles, whether standard models, electric (EV), or autonomous, depend on a tightly integrated network of ECUs communicating over multiple protocols. Gaining visibility into internal ECU communication as well as on the CAN bus network is critical during R&D and validation to ensure safe and reliable operation. Total Phase tools make it easier for engineers to test and debug at both the component and network level.

In-Vehicle Communication Systems

Modern automotive systems rely on a variety of communication protocols to coordinate data flow between ECUs, sensors, and subsystems. These include, but are not limited to:

CAN: Used for high-speed, system-wide communication between ECUs. Its robust, fault-tolerant, real-time message delivery makes it ideal for critical systems like powertrain and BMS.

I2C/SPI: Used for short-range, lower-bandwidth communication within ECUs, connecting processors to onboard sensors, controllers, or memory. These may be used in infotainment systems and smart displays.

Other common protocols such as UART and LIN are also used, depending on the architecture and application.

Choosing the Right Total Phase Tool for Automotive ECU Debugging

Total Phase offers a suite of comprehensive tools designed to address the full range of debugging needs in complex vehicle networks. Engineers can debug at both the component level within an ECU and between ECUs on the CAN network, covering tasks like ECU development, validation, and system integration testing.

Depending on the architecture and needs of the system being tested, these tools can be used independently or together. The following are a few examples that demonstrate how they can be applied in common automotive scenarios.

Real-World ECU Debugging Examples

Use Case #1: Debugging Internal ECU Communication (I2C/SPI)

Certain ECUs, especially infotainment or head units, may use I2C or SPI to interface with displays, EEPROMs, or light sensors. These buses facilitate local communication between a processor/MCU and peripheral components.

Examples Include:

• A head unit processor transmitting display commands or graphics data to an LCD over SPI.
• A head unit accessing an external EEPROM over I2C to read or update configuration data used by display, audio, or touch components.

How Total Phase tools are used:

The Promira Serial Platform or Aardvark I2C/SPI Host Adapter helps simulate and validate communication between automotive microcontroller units (MCUs) and sensors/other peripherals.The Beagle I2C/SPI Protocol Analyzer enables passive monitoring for detailed analysis.

1. Emulate Automotive Devices as Master to Validate Communication

• Connect the Promira platform or Aardvark adapter to the Control Center Serial Software or API.
• Configure as a master, emulating an automotive MCU, to communicate with a sensor used in head units, such as an I2C-based ambient light sensor.
• Send read commands to validate proper data retrieval and response timing from the sensor, and verify how the system handles different sensor values and lighting conditions.

2. Emulate Automotive Sensors as Slave Devices

• Connect the Promira platform or Aardvark adapter to the Control Center Serial Software or API.
• Emulate automotive sensors by sending a single fixed response of up to 256 bytes as a slave device.
• Useful for automated test setups where predictable, repeatable sensor data is needed to develop and validate MCU sensor drivers and communication protocols

3. EEPROM or Flash Memory Programming

• Connect the Aardvark adapter or Promira platform to program memory devices via I2C or SPI.
• Use Flash Center Software or API to write configuration data, update firmware, or validate memory content.
• Ideal for updating stored parameters or confirming memory initialization in an ECU under development.

4. Monitor I2C/SPI Traffic in Real Time

• Use the Beagle I2C/SPI Protocol Analyzer to passively capture communication between the automotive MCU and peripheral devices.
• Analyze transactions, data packets, and timing details using Data Center Software.

Use Case #2: Debugging ECU-to-ECU Communication (CAN)

In systems like Battery Management Systems (BMS) or Airbag Control Modules (ACM), the CAN protocol is often used for communicating critical information across the vehicle network.

Common Examples:

• A BMS broadcasting cell voltages or fault alerts
• An ACM signaling a collision event to other ECUs

How Total Phase tools are used:

With its dual-channel capability, the Komodo CAN Duo Interface allows engineers to transmit or monitor CAN data on the bus. It can simultaneously transmit CAN messages on one channel while monitoring bus traffic on the other, or it can monitor two separate CAN buses at the same time, making it a versatile tool for simulating, monitoring, and analyzing CAN traffic.

1. Send and Evaluate Simulated CAN Messages to and from the ECU

• Connect the Komodo interface as an active device using Komodo GUI Software or Komodo Software API.
• Use General CAN Mode to send or receive customized CAN packets to and from other CAN nodes, controlling IDs, data length, and message content.
• Use Batch Mode to automate repetitive CAN message sequences, or automate and customize communication via Python or C/C# for more flexible control.
• Validate how the ECU responds to simulated CAN traffic, ensuring proper handling of commands and alerts.

2. Monitor CAN Protocol Data Sent Between the ECU and Other Nodes

• Connect the Komodo interface as a passive analyzer in Data Center Software.
• Capture and display raw CAN frames on a CAN bus connecting multiple ECUs to validate message formatting and timing.
• By filtering for specific message IDs, confirm that status updates such as State-of-Charge (SoC) from a BMS or impact alerts from an ACM are broadcasted correctly.
• Continuously log CAN data for long-term monitoring and analysis if required.

3. Simultaneously Transmit and Monitor CAN Traffic Using Dual Channels

• Use one Komodo CAN Duo Interface channel in Komodo GUI Software or via the API to transmit simulated CAN messages to the ECU or other nodes.
• At the same time, connect the second channel to Data Center Software to passively monitor and log all CAN traffic on the bus in real time.
• This setup is ideal for modifying and replaying traffic for simulation and debugging.

Watch how the Komodo CAN Duo Interface, along with the Data Center Software and Komodo GUI Software, is used to record and replay CAN traffic in real time, making it easy to sniff, inject, and debug bus activity for more effective ECU development.

4. Emulate ECU Behavior If Hardware Is Not Finalized

• Use the Komodo interface as an active CAN node to prototype ECU behavior during development.
• Automate message sequences with Batch Mode scripting or API control.
• Validate end-to-end system behavior even before physical ECUs or sensors are available, ensuring consistent message flow and system response.