CAPLfunctionVTSvtsStartTrigger

Open topic with navigation

CAPL Functions » VT System » vtsStartTrigger

vtsStartTrigger

Valid for: CANoe DE • CANoe:lite DE

Function Syntax

long SysVarNamespace.SetTriggerParams (eVTSTrigger Trigger, dword SourceChannel, dword EdgeType);

Description

The function starts the specified trigger. It also resets the event counter system variable that is associated to the trigger to 0. To use a trigger it has to be configured using the functions vtsSetTriggerParams and vtsSetTriggerParamsEx.

You can find additional information about VT System triggers on the page Triggers.

Parameters

• Target: Name of the system variable/namespace that will be affected by this function call.
• Trigger: Specifies which trigger is configured. VT1004/VT1104 module: Values see eVTSTrigger.

Return Values

• 0: Successful call
• -1: Call error
• -2: The namespace on which the command was called does not exist, is not a valid VT System namespace or does not support this command.

Example

Example: CAPL Test Module

The following example shows how triggers can be used to measure the width of a pulse, that is the distance between the rising and falling edge of a pulse.

variables
{
    int64 gRiseTime = 0;
    int64 gFallTime = 0;
}

void MainTest ()
{
    MeasurePulseLength();
}

void MeasurePulseLength()
{
    dword trigger1EventCount = 0;
    dword trigger2EventCount = 0;
    int64 pulseWidth = 0;

    enum eVTSTrigger trigger = eVTSTrigger1;
    enum eVTSTriggerSourceChannel sourceChannel = eVTSTriggerSourceChannel1;
    enum eVTSTriggerEdgeType edgeType = eVTSTriggerEdgeTypeRising;
    dword preTriggers = 0;

    double minPulseWidth = 0.0;

    // configure two triggers (one for the rising and one for the falling edge)
    trigger = eVTSTrigger1;
    sourceChannel = eVTSTriggerSourceChannel1;
    edgeType = 0; // rising edge
    preTriggers = 0; // no other trigger as precondition
    minPulseWidth = 0.002; // pulse must have a width of at at least 2ms

    vtsSetTriggerParams( "VTS::IgnitionChannels", trigger, sourceChannel, edgeType);
    vtsSetTriggerParamsEx( "VTS::IgnitionChannels",  trigger, minPulseWidth, 0.0, preTriggers, 0, 0, eVTSTriggerTypeEdge);

    trigger = eVTSTrigger2;
    sourceChannel = eVTSTriggerSourceChannel1;
    edgeType = eVTSTriggerEdgeTypeFalling; // falling edge
    preTriggers = 1; // first bit set: trigger 1 must be activated as a precondition

    vtsSetTriggerParams( "VTS::IgnitionChannels",  trigger, sourceChannel, edgeType);
    vtsSetTriggerParamsEx( "VTS::IgnitionChannels",  trigger, 0.0, 0.0, preTriggers, 0, 0, eVTSTriggerTypeEdge);

    TestWaitForTimeout( 50); // wait some time to make sure the settings are transferred

    // start triggers
    trigger = eVTSTrigger1;
    vtsStartTrigger( "VTS::IgnitionChannels", trigger);
    trigger = eVTSTrigger2;
    vtsStartTrigger( "VTS::IgnitionChannels", trigger);

    // wait some time until a pulse has occurred
    TestWaitForTimeout( 1000);

    // check if pulse was detected and output pulse width
    trigger1EventCount = @sysvar::VTS::IgnitionChannels::Trigger1EventCount;
    trigger2EventCount = @sysvar::VTS::IgnitionChannels::Trigger2EventCount;

    if (trigger1EventCount > 0 && trigger2EventCount > 0)
    {
        pulseWidth = gFallTime - gRiseTime;
        Write( "Pulse width: %.3f µs", (pulseWidth/1000.0));
    }
    else
    {
        Write("No pulse detected!");
    }
}

on sysvar_update sysvar::VTS::IgnitionChannels::Trigger1Event
{
    // save time stamp of rising edge when event occurs
    gRiseTime = sysGetVariableTimeNS( this);
}

on sysvar_update sysvar::VTS::IgnitionChannels::Trigger2Event
{
    // save time stamp of falling edge when event occurs
    gFallTime = sysGetVariableTimeNS( this);
}

StartTrigger