+extern int timer_b_next_oflow, timer_b_step;\r
+\r
+void ym2612_sync_timers(int z80_cycles, int mode_old, int mode_new);\r
+void ym2612_pack_state(void);\r
+void ym2612_unpack_state(void);\r
+\r
+#define TIMER_NO_OFLOW 0x70000000\r
+// tA = 72 * (1024 - NA) / M\r
+#define TIMER_A_TICK_ZCYCLES 17203\r
+// tB = 1152 * (256 - NA) / M\r
+#define TIMER_B_TICK_ZCYCLES 262800 // 275251 broken, see Dai Makaimura\r