In preemptive operational systems ( which it is supposed to be your case ) it is not possible to accurately generate tic time at short intervals. The only feasible option is to use the Interrupt (IRQ) feature for this. In the past I have done this by external interruption with a crystal-timed peripheral board, sending serial preamble command at a precisely defined rate, but I believe there is some better tricky way to do that by using internal system resourses available on the mainboard.