How create a delay 1 nano second or 1 usecond with QTimer in Qt? is it possible?

stackprogramer

How create a delay 1 nanosecond or 1 microsecond with QTimer in Qt? is it possible?
When I used QTimer delay unit is millisecond... my question is how i can create more accurate delay in qt

thanks in advance

 QElapsedTimer timer;
   timer.start();
   function_delay();
 qDebug()<<timer.nsecsElapsed();

For function delay, I used this method but the delay accuracy is 100 microseconds...

 QTimer delay;
                        delay.start();
                        int DelayTime=0;
                        while(DelayTime < delayNS)
                        {
                            jammingDelayTime=timer.nsecsElapsed();
                        }

or

                    std::this_thread::sleep_for(std::chrono::nanoseconds(delayJammingNS));

these methods 100 microseconds is a minimum delay that executed.....I want to delay 1 microsecond or 1 nanosecond...

Christian Ehrlicher

No and I don't see what you want to do with this short timer...

JoeCFD

https://stackoverflow.com/questions/11063978/c-how-to-sleep-for-a-nanosecond

stackprogramer

@stackprogramer said in How create a delay 1 nano second or 1 usecond with QTimer in Qt? is it possible?:

read::sleep_for(std::chrono::nanoseconds(delayJammingNS));

@JoeCFD But I saw this link when I used method

std::this_thread::sleep_for(std::chrono::nanoseconds(1));

delay is measured with QElapsedTimer timer;
but delay that elapses timer show is 100000 nano second not a 1 nano second.....

stackprogramer

my problem is solved with this method...

             std::chrono::nanoseconds(nanosecond).count();

JoeCFD

Are you sure? In that link:
there is the scheduler, which probably allows no sleeps that are shorter than an timeslice (somewhat around 4 ms - 10 ms, depending on your windows and machine). sleeping less than that is not possible

stackprogramer

@JoeCFD said in How to create a delay 1 nanosecond or 1 second with QTimer in Qt? is it possible?:

Are you sure? In that link:
there is the scheduler, which probably allows no sleeps that are shorter than an timeslice (somewhat around 4 ms - 10 ms, depending on your windows and machine). sleeping less than that is not possible

When I used the before method for a nanosecond I measure 100000nano seconds.....the difference was so much....

             std::chrono::nanoseconds(nanosecond).count();

but with the up method, I can delay 1000 nanoseconds or 1micro second about accurately .....

My os is ubuntu,qt,gcc...not windows...
This delay function executed on a QThread....

thanks good time