test.capl

/*
 * CAPL Script: Message Disabling Example
 * Description: This script demonstrates how to intercept and disable a specific CAN message
 * from being transmitted on the bus.
 * Date: July 10, 2025
 */

variables
{
  // Define the ID of the message you want to disable
  const int DISABLED_MESSAGE_ID = 0x123;  // Change this to your target message ID
  
  // Flag to track if message disabling is active
  int isDisabled = 1;  // 1 = disabled, 0 = enabled
}

// This function runs at the start of measurement
on start
{
  write("Message disabling script started");
  write("Message 0x%x is currently %s", DISABLED_MESSAGE_ID, isDisabled ? "DISABLED" : "ENABLED");
}

// This function intercepts all messages before they are sent
on preTransmit *
{
  // Check if the message being transmitted matches our target ID
  if (this.id == DISABLED_MESSAGE_ID && isDisabled)
  {
    // Cancel the transmission of this message
    cancelTransmit();
    
    // Optionally log that we blocked a message
    write("Blocked transmission of message ID: 0x%x", DISABLED_MESSAGE_ID);
  }
}

// Function to toggle message disabling on/off
on key 'D'
{
  isDisabled = !isDisabled;
  write("Message 0x%x is now %s", DISABLED_MESSAGE_ID, isDisabled ? "DISABLED" : "ENABLED");
}

// Alternative method: Using a specific message handler to disable a particular message

// Provide a function to disable a different message ID dynamically
on key '1' ... '9'
{
  // Calculate new message ID based on key press (1-9 → 0x101-0x109)
  int newID = 0x100 + this - '0';
  
  DISABLED_MESSAGE_ID = newID;
  write("Now targeting message ID: 0x%x (Status: %s)", 
        DISABLED_MESSAGE_ID, 
        isDisabled ? "DISABLED" : "ENABLED");
}

// Optional: Function to demonstrate how to disable message by its name
// (requires database with message definitions)
on preTransmit Engine_Status // Replace with your actual message name
{
  if (isDisabled)
  {
    cancelTransmit();
    write("Blocked message 'Engine_Status'");
  }
}