RTEMS 4.6.1 On-Line Library

Clock Manager CLOCK_TICK - Announce a clock tick

RTEMS Ada User's Guide

7.4.3: CLOCK_TICK - Announce a clock tick

CALLING SEQUENCE:

procedure Clock_Tick (
   Result :    out RTEMS.Status_Codes
);

DIRECTIVE STATUS CODES:

RTEMS.SUCCESSFUL - current time obtained successfully

DESCRIPTION:

This directive announces to RTEMS that a system clock tick has occurred. The directive is usually called from the timer interrupt ISR of the local processor. This directive maintains the system date and time, decrements timers for delayed tasks, timeouts, rate monotonic periods, and implements timeslicing.

NOTES:

This directive is typically called from an ISR.

The microseconds_per_tick and ticks_per_timeslice parameters in the Configuration Table contain the number of microseconds per tick and number of ticks per timeslice, respectively.

RTEMS Ada User's Guide