Periodic Signal (dart E)#

The Periodic Signal camera feature on dart E cameras allows you to synchronize image acquisition on multiple cameras.

该功能的使用#

运作原理#

Basler dart E cameras that support the Periodic Signal feature provide an additional camera signal source, PeriodicSignal1. The signal is synchronized to electrical signals applied via the camera's input line 1.

例如，如果您将周期为 0.3 秒的电信号施加到输入线 1，则相机的内部周期信号会进行调整，进而使相机每隔 0.3 秒捕获一次图像。

当您延长或缩短电信号的周期时，相机的内部周期信号需要一段时间才能调整到新的周期。相机的帧速率会相应增加或减少。当您停止施加电信号时，图像采集将停止。

与标准的硬件触发相比，它具有以下优点：

• It allows edge triggering (rising or falling edge, configured via the BslPeriodicSignalActivation parameter). Standard hardware triggering only allows level triggering.
• 因为相机“知道”信号是周期性的，所以它可以预测下一个信号并使相机准备好进行图像采集。这缩短了从检测到触发信号到实际开始曝光之间的时间。
• You can specify a negative trigger delay (configured via the BslPeriodicSignalDelay parameter), which means that the camera acquires images before the electrical signal is actually applied.

配置 Periodic Signal#

要将相机配置为进行同步图像采集：

1. 将相机配置为由 periodic signal 触发：
   1. Set the TriggerMode parameter to On.
   2. Set the TriggerSource parameter to PeriodicSignal1.
2. 配置信号过渡类型：
   • If you want the camera to capture images on the falling edges of the input signal, set the BslPeriodicSignalActivation parameter to FallingEdge.
   • If you want the camera to capture images on the rising edges of the input signal, set the BslPeriodicSignalActivation parameter to RisingEdge.
3. 配置信号延迟：
   • If you want the camera to capture images immediately when the input signal arrives, set the BslPeriodicSignalDelay parameter to 0.
   • If you want the camera to capture images before or after the input signal arrives, set the BslPeriodicSignalDelay parameter to any other value in nanoseconds. For example, if you set the parameter to -500000, the camera acquires an image 0.5 seconds before the next signal is expected to arrive.
4. 通过相机的输入线 1 施加周期性的电信号。

示例代码#

// Configure the camera to be triggered by the periodic signal
// Note: You must set the trigger source first and then the trigger mode
camera.TriggerSource.SetValue(TriggerSource_PeriodicSignal1);
camera.TriggerMode.SetValue(TriggerMode_On);
// Set the transition type to falling edge
camera.BslPeriodicSignalActivation.SetValue(BslPeriodicSignalActivation_FallingEdge);
// Set the signal delay to 0
camera.BslPeriodicSignalDelay.SetValue(0);

INodeMap& nodemap = camera.GetNodeMap();
// Configure the camera to be triggered by the periodic signal
// Note: You must set the trigger source first and then the trigger mode
CEnumParameter(nodemap, "TriggerSource").SetValue("PeriodicSignal1");
CEnumParameter(nodemap, "TriggerMode").SetValue("On");
// Set the transition type to falling edge
CEnumParameter(nodemap, "BslPeriodicSignalActivation").SetValue("FallingEdge");
// Set the signal delay to 0
CIntegerParameter(nodemap, "BslPeriodicSignalDelay").SetValue(0);

// Configure the camera to be triggered by the periodic signal
// Note: You must set the trigger source first and then the trigger mode
camera.Parameters[PLCamera.TriggerSource].SetValue(PLCamera.TriggerSource.PeriodicSignal1);
camera.Parameters[PLCamera.TriggerMode].SetValue(PLCamera.TriggerMode.On);
// Set the transition type to falling edge
camera.Parameters[PLCamera.BslPeriodicSignalActivation].SetValue(PLCamera.BslPeriodicSignalActivation.FallingEdge);
// Set the signal delay to 0
camera.Parameters[PLCamera.BslPeriodicSignalDelay].SetValue(0);

/* 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 */
/* Configure the camera to be triggered by the periodic signal */
/* Note: You must set the trigger source first and then the trigger mode */
errRes = PylonDeviceFeatureFromString(hdev, "TriggerSource", "PeriodicSignal1");
CHECK(errRes);
errRes = PylonDeviceFeatureFromString(hdev, "TriggerMode", "On");
CHECK(errRes);
/* Set the transition type to falling edge */
errRes = PylonDeviceFeatureFromString(hdev, "BslPeriodicSignalActivation", "FallingEdge");
CHECK(errRes);
/* Set the signal delay to 0 */
errRes = PylonDeviceSetIntegerFeature(hdev, "BslPeriodicSignalDelay", 0);
CHECK(errRes);

# Configure the camera to be triggered by the periodic signal
# Note: You must set the trigger source first and then the trigger mode
camera.TriggerSource.Value = "PeriodicSignal1"
camera.TriggerMode.Value = "On"
# Set the transition type to falling edge
camera.BslPeriodicSignalActivation.Value = "FallingEdge"
# Set the signal delay to 0
camera.BslPeriodicSignalDelay.Value = 0

/* 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 */
/* Configure the camera to be triggered by the periodic signal */
errRes = PylonDeviceFeatureFromString(hdev, "TriggerMode", "On");
CHECK(errRes);
errRes = PylonDeviceFeatureFromString(hdev, "TriggerSource", "PeriodicSignal1");
CHECK(errRes);
/* Set the transition type to falling edge */
errRes = PylonDeviceFeatureFromString(hdev, "BslPeriodicSignalActivation", "FallingEdge");
CHECK(errRes);
/* Set the signal delay to 0 */
errRes = PylonDeviceSetIntegerFeature(hdev, "BslPeriodicSignalDelay", 0);
CHECK(errRes);

您还可以使用 pylon Viewer 轻松设置参数。