+//
+// CLOCK.H: System timing support functionality
+//
+// by James L. Hammons
+//
+
#ifndef __CLOCK_H__
#define __CLOCK_H__
#include "types.h"
-void clock_init(void);
-void clock_reset(void);
-void clock_done(void);
-void clock_byte_write(uint32, uint8);
-void clock_word_write(uint32, uint16);
-uint8 clock_byte_read(uint32);
-uint16 clock_word_read(uint32);
+// 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
+#endif // __CLOCK_H__