Delay Function in RTEMS

[Luca Germano]

Hi  to everyone
how is it possible in RTEMS to delay the execution of an instruction for a 
defined number of ticks?
I tried to use nanosleep POSIX function without results. It seems not work 
good. I convert the number of ticks in nanosecons but nanosleep doesn't 
sleep for the defined ticks period.
Someone used this function or know another RTEMS function that is possible 
to use for this purpose?
Thanks