Trigger Selector#

The Trigger Selector camera feature allows you to select which trigger type should be configured.

Once selected, you can use the trigger type for a number of camera configuration tasks, e.g., enabling hardware triggering.

Using the Feature#

Selecting a Trigger Type#

To select a trigger type, set the TriggerSelector parameter to one of the following values (if available):

Common Tasks#

Once you have selected a trigger type, you can do the following:

Task Feature
Enabling or disabling the selected trigger type Trigger Mode
Selecting the input line or software command to act as the source for the trigger type selected Trigger Source
Selecting the signal transition necessary for activating the trigger type selected Trigger Activation
Configuring a delay between the receipt of a hardware signal and the moment when the trigger type selected becomes effective Trigger Delay

Available Trigger Types#

Frame Burst Start (= Acquisition Start), End, and Active Trigger#

Info

The Frame Burst Start trigger and the Acquisition Start trigger are identical, only the names differ. The naming depends on your camera model. In the following, the term "Frame Burst Start trigger" is used to describe both types.

If available, you can use the Frame Burst Start, End, and Active triggers to control the acquisition of a series of images (a "burst" of images).

The number of images per series is specified by the AcquisitionBurstFrameCount parameter. The maximum number of images per series depends on your camera model.

By default, these triggers are disabled, and the camera acquires single images only.

If you enable these triggers and the camera receives the corresponding signal via the trigger source configured, the following happens:

  • Frame Burst Start: The camera initializes the acquisition of a series of images.
    If the Frame Start trigger is enabled, the camera is now ready to receive Frame Start trigger signals.
    If the Frame Start trigger is disabled and the Exposure Start trigger is enabled, the camera automatically initializes the next image.
    If the Frame Start trigger is disabled and the Exposure Start trigger is also disabled or not available, the camera automatically acquires the entire series of images.
  • Frame Burst End: The camera finalizes the acquisition of a series of images.
    If this trigger is disabled or not available, the camera automatically finalizes the series after the last image acquisition.
  • Frame Burst Active: When the trigger signal rises, the camera generates a Frame Burst Start trigger signal. When the trigger signal falls, the camera generates a Frame Burst End trigger signal. You can change this behavior using the Trigger Activation feature.

Frame Start, End, and Active Trigger#

Info

  • If you want to use any of these triggers, the exposure mode must be set to Timed or TriggerWidth.
  • If the exposure mode is set to TriggerControlled, these triggers can't be enabled, i.e., their TriggerMode setting will permanently be set to Off.

If available, you can use the Frame Start, End, and Active triggers to control the acquisition of a single image. These are the trigger types used most commonly. In most image applications, you will only need to configure these trigger types.

By default, these triggers are disabled, and the camera controls image acquisition automatically.

If you enable these triggers and the camera receives the corresponding signal via the trigger source configured, the following happens:

  • Frame Start: The camera initializes the acquisition of one image.
    If the Exposure Start trigger is enabled, the camera is now ready to receive Exposure Start trigger signals.
    If the Exposure Start trigger is not available or disabled, the camera automatically starts exposing the image. Note that in this case, exposure starts with a delay (see exposure start delay).
  • Frame End: The camera finalizes the acquisition of one image.
    If this trigger is disabled or not available, the camera automatically finalizes image acquisition after exposure.
  • Frame Active: When the trigger signal rises, the camera generates a Frame Start trigger signal. When the trigger signal falls, the camera generates a Frame End trigger signal. You can change this behavior using the Trigger Activation feature.

Exposure Start, End, and Active Trigger#

If available, you can use the Exposure Start, End, and Active triggers to control the exposure of a single image.

Info

  • If you want to use any of these triggers, the exposure mode must be set to TriggerControlled.
  • If the exposure mode is set to Timed or TriggerWidth, these triggers can't be enabled, i.e., their TriggerMode setting will permanently be set to Off.
  • If you want to use the Exposure Start and End triggers, you must enable both for them to work.

By default, these triggers are disabled, and the camera exposes images automatically.

If you enable these triggers, set the exposure mode to TriggerControlled, and the camera receives the corresponding signal via the trigger source configured, the following happens:

  • Exposure Start: The camera starts exposing one image.
  • Exposure End: The camera stops exposing one image.
  • Exposure Active: When the trigger signal rises, the camera generates an Exposure Start trigger signal. When the trigger signal falls, the camera generates an Exposure End trigger signal. You can change this behavior using the Trigger Activation feature.

Using the Trigger Types#

Use Case 1: Frame Burst Triggering#

Assume you want to trigger the acquisition of a series of images with only one trigger signal.

To achieve this, enable the Frame Burst Start trigger and disable all other available trigger types. Also, set the AcquisitionBurstFrameCount parameter to 3.

This way, every time the camera successfully receives a Frame Burst Start trigger signal, the camera automatically acquires a complete series of three images.

Afterwards, the camera waits for the next Frame Burst Start trigger signal. On the next trigger signal, the camera acquires another 3 images, and so on.

Timing Diagram for Use Case 1

Use Case 2: Exposure Triggering#

Assume that you want to avoid the exposure start delay, i.e., start exposure as fast as possible after applying a trigger signal. Also assume that the Exposure Start trigger is available for your camera.

In this case, set the exposure mode to TriggerControlled, enable the Frame Start trigger and the Exposure Start trigger, and disable all other available trigger types.

This way, every time the camera successfully receives a Frame Start trigger signal, the camera initializes image acquisition, but does not yet start exposing. Instead, the camera waits in its prepared state and is ready to expose immediately when receiving an Exposure Start trigger signal.

After the image has been exposed, the camera ignores all further Exposure Start trigger signals. You must apply a new Frame Start trigger signal to initialize the next image acquisition.

Specifics#

Show all camera models

Camera Model Available Trigger Types Maximum Number of Images per Series
a2A1920-51gcBAS Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
a2A1920-51gmBAS Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
a2A1920-160ucBAS Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
a2A1920-160umBAS Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
a2A3840-13gcBAS tbd tbd
a2A3840-13gmBAS tbd tbd
a2A3840-45ucBAS tbd tbd
a2A3840-45umBAS tbd tbd
acA640-90gc Frame Start
Aquisition Start
255
acA640-90gm Frame Start
Aquisition Start
255
acA640-90uc Frame Start
Frame Burst Start
255
acA640-90um Frame Start
Frame Burst Start
255
acA640-120gc Frame Start
Aquisition Start
255
acA640-120gm Frame Start
Aquisition Start
255
acA640-120uc Frame Start
Frame Burst Start
255
acA640-120um Frame Start
Frame Burst Start
255
acA640-121gm -"Frame Start" -"Aquisition Start 255
acA640-300gc Frame Start
Acquisition Start
255
acA640-300gm -"Frame Start" -"Aquisition Start 255
acA640-750uc Frame Start
Frame Burst Start
255
acA640-750um Frame Start
Frame Burst Start
255
acA720-290gc Frame Start
Acquisition Start
255
acA720-290gm Frame Start
Acquisition Start
255
acA720-520uc Frame Start
Frame Burst Start
255
acA720-520um Frame Start
Frame Burst Start
255
acA780-75gc Frame Start
Acquisition Start
255
acA780-75gm Frame Start
Acquisition Start
255
acA800-200gc Frame Start
Acquisition Start
255
acA800-200gm Frame Start
Acquisition Start
255
acA800-510uc Frame Start
Frame Burst Start
255
acA800-510um Frame Start
Frame Burst Start
255
acA1280-60gc Frame Start
Acquisition Start
255
acA1280-60gm Frame Start
Acquisition Start
255
acA1300-22gc Frame Start
Acquisition Start
255
acA1300-22gm Frame Start
Acquisition Start
255
acA1300-30gc Frame Start
Acquisition Start
255
acA1300-30gm Frame Start
Acquisition Start
255
acA1300-30uc Frame Start
Frame Burst Start
255
acA1300-30um Frame Start
Frame Burst Start
255
acA1300-60gc Frame Start
Acquisition Start
255
acA1300-60gm Frame Start
Acquisition Start
255
acA1300-60gmNIR Frame Start
Acquisition Start
255
acA1300-75gc Frame Start
Acquisition Start
255
acA1300-75gm Frame Start
Acquisition Start
255
acA1300-200uc Frame Start
Frame Burst Start
255
acA1300-200um Frame Start
Frame Burst Start
255
acA1440-73gc Frame Start
Acquisition Start
255
acA1440-73gm Frame Start
Acquisition Start
255
acA1440-220uc Frame Start
Frame Burst Start
255
acA1440-220um Frame Start
Frame Burst Start
255
acA1600-20gc Frame Start
Acquisition Start
255
acA1600-20gm Frame Start
Acquisition Start
255
acA1600-20uc Frame Start
Frame Burst Start
255
acA1600-20um Frame Start
Frame Burst Start
255
acA1600-60gc Frame Start
Acquisition Start
255
acA1600-60gm Frame Start
Acquisition Start
255
acA1920-25gc Frame Start
Acquisition Start
255
acA1920-25gm Frame Start
Acquisition Start
255
acA1920-25uc Frame Start
Frame Burst Start
255
acA1920-25um Frame Start
Frame Burst Start
255
acA1920-40gc Frame Start
Acquisition Start
255
acA1920-40gm Frame Start
Acquisition Start
255
acA1920-40uc Frame Start
Frame Burst Start
255
acA1920-40ucMED Frame Start
Frame Burst Start
255
acA1920-40um Frame Start
Frame Burst Start
255
acA1920-40umMED Frame Start
Frame Burst Start
255
acA1920-48gc Frame Start
Acquisition Start
255
acA1920-48gm Frame Start
Acquisition Start
255
acA1920-50gc Frame Start
Acquisition Start
255
acA1920-50gm Frame Start
Acquisition Start
255
acA1920-150uc Frame Start
Frame Burst Start
255
acA1920-150um Frame Start
Frame Burst Start
255
acA1920-155uc Frame Start
Frame Burst Start
255
acA1920-155ucMED Frame Start
Frame Burst Start
255
acA1920-155um Frame Start
Frame Burst Start
255
acA1920-155umMED Frame Start
Frame Burst Start
255
acA2000-50gc Frame Start
Acquisition Start
65535
acA2000-50gm Frame Start
Acquisition Start
65535
acA2000-50gmNIR Frame Start
Acquisition Start
65535
acA2000-165uc Frame Start
Frame Burst Start
255
acA2000-165um Frame Start
Frame Burst Start
255
acA2000-165umNIR Frame Start
Frame Burst Start
255
acA2040-25gc Frame Start
Acquisition Start
65535
acA2040-25gm Frame Start
Acquisition Start
65535
acA2040-25gmNIR Frame Start
Acquisition Start
65535
acA2040-35gc Frame Start
Acquisition Start
255
acA2040-35gm Frame Start
Acquisition Start
255
acA2040-55uc Frame Start
Frame Burst Start
255
acA2040-55um Frame Start
Frame Burst Start
255
acA2040-90uc Frame Start
Frame Burst Start
255
acA2040-90um Frame Start
Frame Burst Start
255
acA2040-90umNIR Frame Start
Frame Burst Start
255
acA2040-120uc Frame Start
Frame Burst Start
255
acA2040-120um Frame Start
Frame Burst Start
255
acA2440-20gc Frame Start
Acquisition Start
255
acA2440-20gm Frame Start
Acquisition Start
255
acA2440-35uc Frame Start
Frame Burst Start
255
acA2440-35ucMED Frame Start
Frame Burst Start
255
acA2440-35um Frame Start
Frame Burst Start
255
acA2440-35umMED Frame Start
Frame Burst Start
255
acA2440-75uc Frame Start
Frame Burst Start
255
acA2440-75ucMED Frame Start
Frame Burst Start
255
acA2440-75um Frame Start
Frame Burst Start
255
acA2440-75umMED Frame Start
Frame Burst Start
255
acA2500-14gc Frame Start
Acquisition Start
255
acA2500-14gm Frame Start
Acquisition Start
255
acA2500-14uc Frame Start
Frame Burst Start
255
acA2500-14um Frame Start
Frame Burst Start
255
acA2500-20gc Frame Start
Acquisition Start
255
acA2500-20gcMED Frame Start
Acquisition Start
255
acA2500-20gm Frame Start
Acquisition Start
255
acA2500-20gmMED Frame Start
Acquisition Start
255
acA2500-60uc Frame Start
Frame Burst Start
255
acA2500-60um Frame Start
Frame Burst Start
255
acA3088-16gc Frame Start
Acquisition Start
255
acA3088-16gm Frame Start
Acquisition Start
255
acA3088-57uc Frame Start
Frame Burst Start
255
acA3088-57um Frame Start
Frame Burst Start
255
acA3800-10gc Frame Start
Acquisition Start
255
acA3800-10gm Frame Start
Acquisition Start
255
acA3800-14uc Frame Start
Frame Burst Start
255
acA3800-14um Frame Start
Frame Burst Start
255
acA4024-8gc Frame Start
Acquisition Start
255
acA4024-8gm Frame Start
Acquisition Start
255
acA4024-29uc Frame Start
Frame Burst Start
255
acA4024-29um Frame Start
Frame Burst Start
255
acA4096-11gc Frame Start
Acquisition Start
255
acA4096-11gm Frame Start
Acquisition Start
255
acA4096-30uc Frame Start
Frame Burst Start
255
acA4096-30ucMED Frame Start
Frame Burst Start
255
acA4096-30um Frame Start
Frame Burst Start
255
acA4096-30umMED Frame Start
Frame Burst Start
255
acA4096-40uc Frame Start
Frame Burst Start
255
acA4096-40ucMED Frame Start
Frame Burst Start
255
acA4096-40um Frame Start
Frame Burst Start
255
acA4096-40umMED Frame Start
Frame Burst Start
255
acA4112-8gc Frame Start
Acquisition Start
255
acA4112-8gm Frame Start
Acquisition Start
255
acA4112-20uc Frame Start
Frame Burst Start
255
acA4112-20ucMED Frame Start
Frame Burst Start
255
acA4112-20um Frame Start
Frame Burst Start
255
acA4112-20umMED Frame Start
Frame Burst Start
255
acA4112-30uc Frame Start
Frame Burst Start
255
acA4112-30ucMED Frame Start
Frame Burst Start
255
acA4112-30um Frame Start
Frame Burst Start
255
acA4112-30umMED Frame Start
Frame Burst Start
255
acA4600-7gc Frame Start
Acquisition Start
255
acA4600-10uc Frame Start
Frame Burst Start
255
acA5472-5gc Frame Start
Acquisition Start
255
acA5472-5gm Frame Start
Acquisition Start
255
acA5472-17uc Frame Start
Frame Burst Start
255
acA5472-17um Frame Start
Frame Burst Start
255
boA4096-93cc Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
boA4096-93cm Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
boA4112-68cc Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
boA4112-68cm Frame Start
Frame End
Frame Active
Frame Burst Start
Frame Burst End
Frame Burst Active
Exposure Start
Exposure End
Exposure Active
1023
daA1280-54lc Frame Start N/A
daA1280-54lm Frame Start N/A
daA1280-54uc Frame Start N/A
daA1280-54um Frame Start N/A
daA1600-60lc Frame Start N/A
daA1600-60lm Frame Start N/A
daA1600-60uc Frame Start N/A
daA1600-60um Frame Start N/A
daA1920-15um Frame Start N/A
daA1920-30uc Frame Start N/A
daA1920-30um Frame Start N/A
daA2500-14lc Frame Start N/A
daA2500-14lm Frame Start N/A
daA2500-14uc Frame Start N/A
daA2500-14um Frame Start N/A
daA2500-60mc Trigger Selector feature not supported Trigger Selector feature not supported
puA1280-54uc Frame Start N/A
puA1280-54um Frame Start N/A
puA1600-60uc Frame Start N/A
puA1600-60um Frame Start N/A
puA1920-30uc Frame Start N/A
puA1920-30um Frame Start N/A
puA2500-14uc Frame Start N/A
puA2500-14um Frame Start N/A

Sample Code#

ace classic/U/L GigE Cameras#

// Select and enable the Frame Start trigger
camera.TriggerSelector.SetValue(TriggerSelector_FrameStart);
camera.TriggerMode.SetValue(TriggerMode_On);
// Select and enable the Acquisition Start trigger
camera.TriggerSelector.SetValue(TriggerSelector_AcquisitionStart);
camera.TriggerMode.SetValue(TriggerMode_On);
// Set the number of images to be acquired per Acquisition Start trigger signal to 3
camera.AcquisitionFrameCount.SetValue(3);
INodeMap& nodemap = camera.GetNodeMap();
// Select and enable the Frame Start trigger
CEnumerationPtr(nodemap.GetNode("TriggerSelector"))->FromString("FrameStart");
CEnumerationPtr(nodemap.GetNode("TriggerMode"))->FromString("On");
// Select and enable the Acquisition Start trigger
CEnumerationPtr(nodemap.GetNode("TriggerSelector"))->FromString("AcquisitionStart");
CEnumerationPtr(nodemap.GetNode("TriggerMode"))->FromString("On");
// Set the number of images to be acquired per Acquisition Start trigger signal to 3
CIntegerPtr(nodemap.GetNode("AcquisitionFrameCount"))->SetValue(3);
INodeMap& nodemap = camera.GetNodeMap();
// Select and enable the Frame Start trigger
CEnumParameter(nodemap, "TriggerSelector").SetValue("FrameStart");
CEnumParameter(nodemap, "TriggerMode").SetValue("On");
// Select and enable the Acquisition Start trigger
CEnumParameter(nodemap, "TriggerSelector").SetValue("AcquisitionStart");
CEnumParameter(nodemap, "TriggerMode").SetValue("On");
// Set the number of images to be acquired per Acquisition Start trigger signal to 3
CIntegerParameter(nodemap, "AcquisitionFrameCount").SetValue(3);
// Select and enable the Frame Start trigger
camera.Parameters[PLCamera.TriggerSelector].SetValue(PLCamera.TriggerSelector.FrameStart);
camera.Parameters[PLCamera.TriggerMode].SetValue(PLCamera.TriggerMode.On);
// Select and enable the Acquisition Start trigger
camera.Parameters[PLCamera.TriggerSelector].SetValue(PLCamera.TriggerSelector.AcquisitionStart);
camera.Parameters[PLCamera.TriggerMode].SetValue(PLCamera.TriggerMode.On);
// Set the number of images to be acquired per Acquisition Start trigger signal to 3
camera.Parameters[PLCamera.AcquisitionFrameCount].SetValue(3);
// Select and enable the Frame Start trigger
Pylon.DeviceFeatureFromString(hdev, "TriggerSelector", "FrameStart");
Pylon.DeviceFeatureFromString(hdev, "TriggerMode", "On");
// Select and enable the Acquisition Start trigger
Pylon.DeviceFeatureFromString(hdev, "TriggerSelector", "AcquisitionStart");
Pylon.DeviceFeatureFromString(hdev, "TriggerMode", "On");
// Set the number of images to be acquired per Acquisition Start trigger signal to 3
Pylon.DeviceSetIntegerFeature(hdev, "AcquisitionFrameCount", 3);
/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
/* Select and enable the Frame Start trigger */
errRes = PylonDeviceFeatureFromString(hdev, "TriggerSelector", "FrameStart");
CHECK(errRes);
errRes = PylonDeviceFeatureFromString(hdev, "TriggerMode", "On");
CHECK(errRes);
/* Select and enable the Acquisition Start trigger */
errRes = PylonDeviceFeatureFromString(hdev, "TriggerSelector", "AcquisitionStart");
CHECK(errRes);
errRes = PylonDeviceFeatureFromString(hdev, "TriggerMode", "On");
CHECK(errRes);
/* Set the number of images to be acquired per Acquisition Start trigger signal to 3 */
errRes = PylonDeviceSetIntegerFeature(hdev, "AcquisitionFrameCount", 3);
CHECK(errRes);

Other Cameras#

// Select and enable the Frame Start trigger
camera.TriggerSelector.SetValue(TriggerSelector_FrameStart);
camera.TriggerMode.SetValue(TriggerMode_On);
// Select and enable the Frame Burst Start trigger
camera.TriggerSelector.SetValue(TriggerSelector_FrameBurstStart);
camera.TriggerMode.SetValue(TriggerMode_On);
// Set the number of images to be acquired per Frame Burst Start trigger signal to 3
camera.AcquisitionBurstFrameCount.SetValue(3);
INodeMap& nodemap = camera.GetNodeMap();
// Select and enable the Frame Start trigger
CEnumerationPtr(nodemap.GetNode("TriggerSelector"))->FromString("FrameStart");
CEnumerationPtr(nodemap.GetNode("TriggerMode"))->FromString("On");
// Select and enable the Frame Burst Start trigger
CEnumerationPtr(nodemap.GetNode("TriggerSelector"))->FromString("FrameBurstStart");
CEnumerationPtr(nodemap.GetNode("TriggerMode"))->FromString("On");
// Set the number of images to be acquired per Frame Burst Start trigger signal to 3
CIntegerPtr(nodemap.GetNode("AcquisitionBurstFrameCount"))->SetValue(3);
INodeMap& nodemap = camera.GetNodeMap();
// Select and enable the Frame Start trigger
CEnumParameter(nodemap, "TriggerSelector").SetValue("FrameStart");
CEnumParameter(nodemap, "TriggerMode").SetValue("On");
// Select and enable the Frame Burst Start trigger
CEnumParameter(nodemap, "TriggerSelector").SetValue("FrameBurstStart");
CEnumParameter(nodemap, "TriggerMode").SetValue("On");
// Set the number of images to be acquired per Frame Burst Start trigger signal to 3
CIntegerParameter(nodemap, "AcquisitionBurstFrameCount").SetValue(3);
// Select and enable the Frame Start trigger
camera.Parameters[PLCamera.TriggerSelector].SetValue(PLCamera.TriggerSelector.FrameStart);
camera.Parameters[PLCamera.TriggerMode].SetValue(PLCamera.TriggerMode.On);
// Select and enable the Frame Burst Start trigger
camera.Parameters[PLCamera.TriggerSelector].SetValue(PLCamera.TriggerSelector.FrameBurstStart);
camera.Parameters[PLCamera.TriggerMode].SetValue(PLCamera.TriggerMode.On);
// Set the number of images to be acquired per Frame Burst Start trigger signal to 3
camera.Parameters[PLCamera.AcquisitionBurstFrameCount].SetValue(3);
// Select and enable the Frame Start trigger
Pylon.DeviceFeatureFromString(hdev, "TriggerSelector", "FrameStart");
Pylon.DeviceFeatureFromString(hdev, "TriggerMode", "On");
// Select and enable the Frame Burst Start trigger
Pylon.DeviceFeatureFromString(hdev, "TriggerSelector", "FrameBurstStart");
Pylon.DeviceFeatureFromString(hdev, "TriggerMode", "On");
// Set the number of images to be acquired per Frame Burst Start trigger signal to 3
Pylon.DeviceSetIntegerFeature(hdev, "AcquisitionBurstFrameCount", 3);
/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
/* Select and enable the Frame Start trigger */
errRes = PylonDeviceFeatureFromString(hdev, "TriggerSelector", "FrameStart");
CHECK(errRes);
errRes = PylonDeviceFeatureFromString(hdev, "TriggerMode", "On");
CHECK(errRes);
/* Select and enable the Frame Burst Start trigger */
errRes = PylonDeviceFeatureFromString(hdev, "TriggerSelector", "FrameBurstStart");
CHECK(errRes);
errRes = PylonDeviceFeatureFromString(hdev, "TriggerMode", "On");
CHECK(errRes);
/* Set the number of images to be acquired per Frame Burst Start trigger signal to 3 */
errRes = PylonDeviceSetIntegerFeature(hdev, "AcquisitionBurstFrameCount", 3);
CHECK(errRes);

You can also use the pylon Viewer to easily set the parameters.