tried to adjust timers using formulae

[picodrive.git] / Pico / PicoInt.h

diff --git a/Pico/PicoInt.h b/Pico/PicoInt.h
index c2f8b60..4ac115f 100644 (file)
--- a/Pico/PicoInt.h
+++ b/Pico/PicoInt.h
@@ -480,6 +480,10 @@ void ym2612_pack_state(void);
 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
 \r
 #define timers_cycle() \\r
   if (timer_a_next_oflow > 0 && timer_a_next_oflow < TIMER_NO_OFLOW) \\r
@@ -490,8 +494,8 @@ void ym2612_unpack_state(void);
 \r
 #define timers_reset() \\r
   timer_a_next_oflow = timer_b_next_oflow = TIMER_NO_OFLOW; \\r
-  timer_a_step = timer_a_offset = 16495 * 1024; \\r
-  timer_b_step = timer_b_offset = 263912 * 256;\r
+  timer_a_step = timer_a_offset = TIMER_A_TICK_ZCYCLES * 1024; \\r
+  timer_b_step = timer_b_offset = TIMER_B_TICK_ZCYCLES * 256;\r
 \r
 \r
 // VideoPort.c\r