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+@chapter = The Clock Driver
+
+@subsection = Introduction
+
+The clock driver aims at giving a steady time basis to the kernel, so that
+the RTEMS primitives that need a clock tick work properly. <insert a link
+to the Clock Driver defs>
+
+The clock driver is located in the clock directory of the BSP. 
+
+@subsection = Primitives
+
+@subsection = Initialization
+
+The major and minor numbers of the clock driver can be made available to
+the others, such as the Shared Memory Driver. 
+
+Then you have to program your integrated processor periodic interval timer
+so that an interrupt is generated every m microseconds, where m =
+BSP_Configuration.microseconds_per_tick. Sometimes the periodic interval
+timer can use a prescaler so you have to look carefully at your user's
+manual to determine the correct value. 
+
+You must use the RTEMS primitive to put your clock interrupt routine in
+the VBR: 
+
+@example
+rtems_interrupt_catch (InterruptHandler, CONSOLE_VECTOR, &old_handler); 
+@end example
+
+@subsection = The clock interrupt subroutine
+
+It only has to inform the kernel that a ticker has elapsed, so call : 
+
+@example
+rtems_clock_tick(); 
+@end example
+