Euresys Coaxlink, Руководство программиста

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Euresys::EGrabber Coaxlink Programmer's Guide
Of course, the application must also be aware that it might receive notifications for events of type
X
that are
older than notifications of events of type
Y
that have already been received and processed. Aer all, this is the
differentiating factor between the
single thread
and
multi thread
models.
To give the user maximum flexibility, we support all three callback models. This is why
Euresys::EGrabber
exists
in different flavors. So far, we have eluded the meaning of the angle brackets in
EGrabber<>
. The
EGrabber
class
is actually a
template class
, i.e., a class that is parameterized by another type:
• In this case, the template parameter is the callback model to use: one of
CallbackOnDemand
,
CallbackSingleThread
or
CallbackMultiThread
.
• The empty
<>
are used to select the default template parameter, which is
CallbackOnDemand
.
• The types of grabber that can be instantiated are:
•
EGrabber<CallbackOnDemand>
•
EGrabber<CallbackSingleThread>
•
EGrabber<CallbackMultiThread>
•
EGrabber<>
which is equivalent to
EGrabber<CallbackOnDemand>
• The
EGrabber
header file also defines the following type aliases (synonyms):
typedef EGrabber<CallbackOnDemand> EGrabberCallbackOnDemand;
typedef EGrabber<CallbackSingleThread> EGrabberCallbackSingleThread;
typedef EGrabber<CallbackMultiThread> EGrabberCallbackMultiThread;
• The .NET generics don't quite match the C++ templates, so in .NET the template
EGrabber
class does not
exist and we must use one of
EGrabberCallbackOnDemand
,
EGrabberCallbackSingleThread
or
EGrabberCallbackMultiThread
.
Events and callbacks examples
On demand callbacks
This program displays basic information about CIC events generated by a grabber:
#include <iostream>
#include <EGrabber.h>
using namespace Euresys;
// 1
class MyGrabber : public EGrabber<CallbackOnDemand> { // 2
public :
MyGrabber(EGenTL &gentl) : EGrabber<CallbackOnDemand>(gentl) { // 3
runScript( "config.js" ); // 4
enableEvent<CicData>();
// 5
reallocBuffers(3);
start();
}
private :
virtual void onCicEvent( const CicData &data) {
std::cout << "timestamp: " << std::dec << data.timestamp << " us, " // 6
<< "numid: 0x" << std::hex << data.numid // 6
<< " (" << getEventDescription(data.numid) << ")"
<< std::endl;
}
};
int main() {
try {
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