-# define TICK_MILLISECS (1000/TICK_FREQUENCY) /* ms per tick */
-
-/* Context switch timing constants. Context switches happen after a
- * whole number of ticks, the default being every tick.
- */
-#define CS_MIN_MILLISECS TICK_MILLISECS /* milliseconds per slice */
-
-typedef void (*TickProc)(int);
-
-extern int startTimer(nat ms);
-extern int stopTimer(void);