Base files

doc/bsp_howto/timer.t

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+@chapter = Timer Driver
+
+You can program the timer driver for your own needs, but here are two uses
+of it: 
+
+@subsection = UART'S FIFO Full Mode
+
+The gen68340 BSP is an example of the use of the timer to support the UART
+input FIFO full mode (FIFO means First In First Out and roughly means
+buffer). This mode consists in the UART raising an interrupt when n
+characters have been received (n is the UA RT's FIFO length). It results
+in a lower interrupt processing time, but the problem is that a scanf
+primitive will block on a receipt of less than n characters. The solution
+is to set a timer that will check whether there are some characters
+waiting in th e UART's input FIFO. The delay time has to be set carefully
+otherwise high rates will be broken: 
+
+@itemize @bullet
+
+@item if no character was received last time the interrupt subroutine was
+entered, set a long delay,
+
+@item otherwise set the delay to the delay needed for n characters
+receipt. 
+
+@end itemize
+
+@subsection = Measuring RTEMS Primitives Time
+
+RTEMS Timing Test Suite needs a timer support. You have to provide two
+primitives: 
+
+
+
+Function
+
+Description
+
+@example
+void Timer_initialize (void)
+@end example
+
+Initialize the timer to be a counter to the microsecond.
+
+@example
+int Read_timer (void)
+@end example
+
+Returns the number of microseconds elapsed since the last call to
+Timer_initialize. 
+
+@example
+rtems_status_code Empty_function (void)
+
+return RTEMS_SUCCESSFUL;
+@end example
+
+@example
+void Set_find_average_overhead (rtems_boolean find_flag)
+@end example
+
+DOES NOTHING ????????????????????????????????????????????????????????????????????????????????????????????????????
+
+		
+
+