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Data Injection Overview

Data injection lets you transmit CAN frames from TrueFidelity while a system is running. Use it to simulate sensors, reproduce edge cases, or validate control strategies in a controlled environment. Injection is managed inside the Signal Player & Injection panel rather than a separate window.

When to Use Injection

  • Simulate missing sensors or altered signals during bench testing.
  • Reproduce field issues without waiting for exact conditions.
  • Validate firmware responses to specific message sequences.
  • Blend simulated messages with recorded playback traffic.

Safety First

  • Perform injection only in controlled test environments.
  • Keep a quick way to stop the system if something goes wrong.
  • Document injected signals so results are traceable.

Starting Injection

Step 1: Start Your System

Before injection can work, your system must be running. Click the Start System button (play icon) in the main toolbar.

Main toolbar with Start System button highlighted

Wait until all ECUs show a green Running status in the ECU Status panel.

ECU Status panel showing three ECUs in Running state

The status bar at the bottom should also confirm containers are running (e.g., "8 / 8 Containers Running").

Step 2: Open Signal Player & Injection

Navigate to View > Panels > Signal Player & Injection to open the panel.

View menu showing Panels submenu with Signal Player & Injection option highlighted

Alternatively, switch to the Network Analysis layout from View > Layouts > Network Analysis, which provides a comprehensive view for CAN bus analysis.

Network Analysis layout showing Signal Viewer, Network Traffic, and Signal Chart panels

Step 3: Understand the Panel Layout

The Signal Player & Injection panel contains both playback and injection controls.

Signal Player & Injection panel with playback and injection controls

Key areas in the panel:

  • Playback controls (left) - Play, Pause, Stop buttons for BLF dataset playback.
  • Injection controls (right) - Start all, Pause all, Stop all, Clear all buttons.
  • Sync with playback toggle - Align injection timing with playback.
  • Networks list (bottom) - Shows matched frames between your dataset and DBC file. Verify the correct CAN bus is selected here.

Networks list showing CAN bus selection and matched frames

Step 4: Configure Signal Injection (Optional)

To configure individual signal values for injection, click on a signal in the network tree.

Signal tree showing expandable frames and signals for injection

This opens the signal options dialog:

Signal injection options dialog showing override value, options, and length settings

In the signal options dialog you can:

  • Override value - Enter a physical value to inject (e.g., vehicle speed in km/h).
  • Start with playback - Automatically begin injecting when playback starts.
  • Include in Start all - Include this signal when using the Start all button.
  • Length - Choose Continuous, Frames count, or Duration-based injection.
  • Value encoding - Select Physical or Raw encoding.

After configuring the signal options, click Save to confirm. Then select the signal for injection by clicking on its checkbox in the signal tree.

Signal selected for injection by clicking the checkbox

Step 5: Start Injection

Use Start all to begin injecting all configured signals. The button turns active (green) when the system is running.

Injection controls with Start all button highlighted

Step 6: Control Injection

  • Pause all - Temporarily stop sending without clearing state.
  • Stop all - End injection and reset the run.
  • Clear all - Remove pending injection items from the queue.

Step 7: Sync with Playback (Optional)

If you need injection to line up with recorded playback data, enable Sync with playback before pressing Play. This ensures injected signals start at the same time as playback.

Verifying Injection

Once injection is active, use these panels to confirm frames are being transmitted correctly.

Watch Network Traffic

Open the Network Traffic panel to see live CAN frames on the bus. Injected frames appear alongside other traffic.

Network Traffic panel showing injected CAN frames

Look for:

  • Live indicator - Green "Live" badge confirms real-time capture.
  • CAN ID column - Verify your injected frame IDs appear.
  • DATA column - Check that data bytes match expected values.
  • Filter - Use the filter box to isolate specific CAN IDs.

Check Signal Viewer

The Signal Viewer panel shows decoded signal values in real time. Expand frames to see individual signals update as injection runs.

Signal Viewer panel showing injected signal values updating

Key indicators:

  • Green dots - Signals receiving live updates.
  • Real-time values - Current decoded values (e.g., 48.67 km/h).
  • Active count - Number of signals currently updating.

Monitor ECU Console

Keep the ECU Console open to catch any runtime errors or unexpected behavior from ECUs responding to injected signals.

ECU Console showing log messages from running ECUs

Use the console to:

  • Filter by source - Select specific ECU logs from the dropdown.
  • Watch for errors - Look for ERR or WRN level messages.
  • Pause scrolling - Click Pause to inspect specific log entries.

Troubleshooting Injection

Issue Suggested Fix
Injection controls disabled Start the system and confirm the runtime is connected.
Frames not visible Check the selected network and verify traffic appears in Network Traffic.
Playback works but injection does not Disable Sync with playback and try Start all manually.
Injection causes instability Stop injection and verify ECU configuration and bus load.
Signal values not updating Ensure the DBC file is loaded and signals are selected in Signal Viewer.

Next Steps

  • Review Playback for dataset setup and channel mapping.
  • Use Filters & Search to isolate injected frames quickly.
  • Refer to Controls & Panels for a deeper panel walkthrough.