Where are the Ada packages for interface to RTEMS?

[careri/sed]

According to  "RTEMS Application Ada User's Guide",  the RTEMS directives can be invoked in application program written in Ada.   However,  we can not find the Ada specification packages s for RTEMS in GNAT/RTEMS environment that is created per the guide "Getting Started with GNAT/RTEMS".  Where are the Ada packages for interface to RTEMS?

Thanks,

Rong