+//
+// EVENT.H: System timing support functionality
+//
+// by James L. Hammons
+//
+
+#ifndef __EVENT_H__
+#define __EVENT_H__
+
+#include "types.h"
+
+// Note that these are NTSC timings:
+
+#define RISC_CYCLE_IN_USEC 0.03760684198
+#define M68K_CYCLE_IN_USEC (RISC_CYCLE_IN_USEC * 2)
+#define HORIZ_PERIOD_IN_USEC 63.5555
+
+#define USEC_TO_RISC_CYCLES(u) (uint32)(((u) / RISC_CYCLE_IN_USEC) + 0.5)
+#define USEC_TO_M68K_CYCLES(u) (uint32)(((u) / M68K_CYCLE_IN_USEC) + 0.5)
+
+void InitializeEventList(void);
+void SetCallbackTime(void (* callback)(void), double time);
+void RemoveCallback(void (* callback)(void));
+void AdjustCallbackTime(void (* callback)(void), double time);
+double GetTimeToNextEvent(void);
+void HandleNextEvent(void);
+
+#endif // __EVENT_H__