From be297089d0eef9747c6917f1dae70dfc7046a8e8 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Fri, 11 Jul 2008 20:48:05 +0000
Subject: [PATCH] z80/ym2612 reset handling improved

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@540 be3aeb3a-fb24-0410-a615-afba39da0efa
---
 Pico/MemoryCmn.c      | 73 ++++++++++++++++++++++---------------------
 Pico/PicoFrameHints.c |  6 ++--
 Pico/sound/ym2612.c   |  3 +-
 3 files changed, 42 insertions(+), 40 deletions(-)

diff --git a/Pico/MemoryCmn.c b/Pico/MemoryCmn.c
index 6493207..fbe5041 100644
--- a/Pico/MemoryCmn.c
+++ b/Pico/MemoryCmn.c
@@ -60,27 +60,46 @@ u32 z80ReadBusReq(void)
   return d|0x80;
 }
 
-#ifndef _ASM_MEMORY_C
-static
-#endif
-void z80WriteBusReq(u32 d)
+static void z80WriteBusReq(u32 d)
+{
+  d&=1; d^=1;
+  elprintf(EL_BUSREQ, "set_zrun: %i->%i [%i] @%06x", Pico.m.z80Run, d, SekCyclesDone(), SekPc);
+  if (d ^ Pico.m.z80Run)
+  {
+    if (d)
+    {
+      z80_cycle_cnt = cycles_68k_to_z80(SekCyclesDone());
+    }
+    else
+    {
+      z80stopCycle = SekCyclesDone();
+      if ((PicoOpt&POPT_EN_Z80) && !Pico.m.z80_reset)
+        PicoSyncZ80(z80stopCycle);
+    }
+    Pico.m.z80Run=d;
+  }
+}
+
+static void z80WriteReset(u32 d)
 {
   d&=1; d^=1;
+  elprintf(EL_BUSREQ, "set_zreset: %i->%i [%i] @%06x", Pico.m.z80_reset, d, SekCyclesDone(), SekPc);
+  if (d ^ Pico.m.z80_reset)
   {
-    if (!d)
+    if (d)
     {
       if ((PicoOpt&POPT_EN_Z80) && Pico.m.z80Run)
-      {
-        z80stopCycle = SekCyclesDone();
-	PicoSyncZ80(z80stopCycle);
-      }
-    } else {
-      if (!Pico.m.z80Run)
-        z80_cycle_cnt = cycles_68k_to_z80(SekCyclesDone());
+        PicoSyncZ80(SekCyclesDone());
+    }
+    else
+    {
+      z80_cycle_cnt = cycles_68k_to_z80(SekCyclesDone());
+      z80_reset();
     }
+    YM2612ResetChip();
+    timers_reset();
+    Pico.m.z80_reset=d;
   }
-  elprintf(EL_BUSREQ, "set_zrun: %i->%i [%i] @%06x", Pico.m.z80Run, d, SekCyclesDone(), SekPc);
-  Pico.m.z80Run=(u8)d;
 }
 
 #ifndef _ASM_MEMORY_C
@@ -161,17 +180,8 @@ void OtherWrite8(u32 a,u32 d)
   if ((a&0xffffe0)==0xa10000)  { IoWrite8(a, d); return; } // I/O ports
 #endif
   if (a==0xa11100)             { z80WriteBusReq(d); return; }
-  if (a==0xa11200) {
-    elprintf(EL_BUSREQ, "write z80Reset: %02x", d);
-    if (!(d&0x1)) { Pico.m.z80_reset = 1; Pico.m.z80Run = 0; YM2612ResetChip(); }
-    else if (Pico.m.z80_reset) {
-      Pico.m.z80_reset = 0;
-      YM2612ResetChip();
-      z80_reset();
-      timers_reset();
-    }
-    return;
-  }
+  if (a==0xa11200)             { z80WriteReset(d);  return; }
+
 #if !defined(_ASM_MEMORY_C) || defined(_ASM_MEMORY_C_AMIPS)
   if ((a&0xff7f00)==0xa06000) // Z80 BANK register
   {
@@ -206,17 +216,8 @@ void OtherWrite16(u32 a,u32 d)
     else elprintf(EL_ANOMALY, "68k z80 write with no bus or reset! [%06x] %04x @ %06x", a, d&0xffff, SekPc);
     return;
   }
-  if (a==0xa11200) {
-    elprintf(EL_BUSREQ, "write z80reset: %04x", d);
-    if (!(d&0x100)) { Pico.m.z80_reset = 1; Pico.m.z80Run = 0; YM2612ResetChip(); }
-    else if (Pico.m.z80_reset) {
-      Pico.m.z80_reset = 0;
-      YM2612ResetChip();
-      z80_reset();
-      timers_reset();
-    }
-    return;
-  }
+  if (a==0xa11200)             { z80WriteReset(d>>8); return; }
+
   if ((a&0xff7f00)==0xa06000) // Z80 BANK register
   {
     Pico.m.z80_bank68k>>=1;
diff --git a/Pico/PicoFrameHints.c b/Pico/PicoFrameHints.c
index 7a372bf..84db382 100644
--- a/Pico/PicoFrameHints.c
+++ b/Pico/PicoFrameHints.c
@@ -124,7 +124,7 @@ static int PicoFrameHints(void)
       emustatus &= ~1;
     else if ((y == 224 || y == line_sample) && PsndOut)
     {
-      if (Pico.m.z80Run && (PicoOpt&POPT_EN_Z80))
+      if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoOpt&POPT_EN_Z80))
         PicoSyncZ80(SekCycleCnt);
       if (ym2612.dacen && PsndDacLine <= y)
         PsndDoDAC(y);
@@ -188,7 +188,7 @@ static int PicoFrameHints(void)
     elprintf(EL_INTS, "vint: @ %06x [%i]", SekPc, SekCycleCnt);
     SekInterrupt(6);
   }
-  if (Pico.m.z80Run && (PicoOpt&POPT_EN_Z80)) {
+  if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoOpt&POPT_EN_Z80)) {
     PicoSyncZ80(SekCycleCnt);
     elprintf(EL_INTS, "zint");
     z80_int();
@@ -246,7 +246,7 @@ static int PicoFrameHints(void)
   }
 
   // sync z80
-  if (Pico.m.z80Run && (PicoOpt&POPT_EN_Z80))
+  if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoOpt&POPT_EN_Z80))
     PicoSyncZ80(Pico.m.pal ? 151809 : 127671); // cycles adjusted for converter
   if (PsndOut && ym2612.dacen && PsndDacLine <= lines-1)
     PsndDoDAC(lines-1);
diff --git a/Pico/sound/ym2612.c b/Pico/sound/ym2612.c
index 56c363a..0c26739 100644
--- a/Pico/sound/ym2612.c
+++ b/Pico/sound/ym2612.c
@@ -1668,6 +1668,8 @@ void YM2612Init_(int clock, int rate)
 	ym2612.OPN.ST.clock = clock;
 	ym2612.OPN.ST.rate = rate;
 
+	OPNSetPres( 6*24 );
+
 	/* Extend handler */
 	YM2612ResetChip_();
 }
@@ -1680,7 +1682,6 @@ void YM2612ResetChip_(void)
 
 	memset(ym2612.REGS, 0, sizeof(ym2612.REGS));
 
-	OPNSetPres( 6*24 );
 	set_timers( 0x30 ); /* mode 0 , timer reset */
 	ym2612.REGS[0x27] = 0x30;
 
-- 
2.39.2