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RTEMS 4.8.0 On-Line Library


Clock Manager CLOCK_SET_NANOSECONDS_EXTENSION - Install the nanoseconds since last tick handler

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7.4.3: CLOCK_SET_NANOSECONDS_EXTENSION - Install the nanoseconds since last tick handler

CALLING SEQUENCE:

NOT SUPPORTED FROM Ada BINDING

DIRECTIVE STATUS CODES:

RTEMS.SUCCESSFUL - clock tick processed successfully
RTEMS.INVALID_ADDRESS - time_buffer is NULL

DESCRIPTION:

This directive is used by the Clock device driver to install the routine which will be invoked by the internal RTEMS method used to obtain a highly accurate time of day. It is usually called during the initialization of the driver.

When the routine is invoked, it will determine the number of nanoseconds which have elapsed since the last invocation of the rtems.clock_tick directive. It should do this as quickly as possible with as little impact as possible on the device used as a clock source.

NOTES:

This directive may be called from an ISR.

This directive is called as part of every service to obtain the current date and time as well as timestamps.


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