PID Controller

I want to develop a PID software and i want Beaglebone Black to be my controller.
I want to have an output at exactly every 200Hz…is that possible?
I am asking that because Beaglebone is running linux…
And the real question is do i have real time system?
Is it possible that linux kernel at the time i want to drive an output(at exactly 200Hz)…to service another task and to delay my PID?

So the question is can i have an accurate time interrupt in Beaglebone?
Or for real time operation do i have to get a simple microcontroller?

Thank you very much in advance for your answers.