From 7b52165dd5d84f134fe2a2d22b6cc95be5361d9a Mon Sep 17 00:00:00 2001
From: ekeeke <ekeeke31@gmail.com>
Date: Sat, 4 Apr 2020 15:27:30 +0200
Subject: [PATCH] [Core/CPU] added Z80 wait-states on 68k bus access (fixes
 Remute Red Eyes demo)

---
 core/memz80.c | 12 +++++++++++-
 core/memz80.h |  2 +-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/core/memz80.c b/core/memz80.c
index fcc1b5b..d8630d5 100644
--- a/core/memz80.c
+++ b/core/memz80.c
@@ -5,7 +5,7 @@
  *  Support for SG-1000, Mark-III, Master System, Game Gear & Mega Drive ports access
  *
  *  Copyright (C) 1998-2003  Charles Mac Donald (original code)
- *  Copyright (C) 2007-2016  Eke-Eke (Genesis Plus GX)
+ *  Copyright (C) 2007-2020  Eke-Eke (Genesis Plus GX)
  *
  *  Redistribution and use of this code or any derivative works are permitted
  *  provided that the following conditions are met:
@@ -111,6 +111,8 @@ unsigned char z80_memory_r(unsigned int address)
     {
       if ((address >> 8) == 0x7F)
       {
+        /* average Z80 wait-states when accessing 68k area */
+        Z80.cycles += 3 * 15;
         return (*zbank_memory_map[0xc0].read)(address);
       }
       return z80_unused_r(address);
@@ -118,6 +120,9 @@ unsigned char z80_memory_r(unsigned int address)
       
     default: /* $8000-$FFFF: 68k bank (32K) */
     {
+      /* average Z80 wait-states when accessing 68k area */
+      Z80.cycles += 3 * 15;
+
       address = zbank | (address & 0x7FFF);
       if (zbank_memory_map[address >> 16].read)
       {
@@ -158,6 +163,8 @@ void z80_memory_w(unsigned int address, unsigned char data)
 
         case 0x7F: /* $7F00-$7FFF: VDP */
         {
+          /* average Z80 wait-states when accessing 68k area */
+          Z80.cycles += 3 * 15;
           (*zbank_memory_map[0xc0].write)(address, data);
           return;
         }
@@ -172,6 +179,9 @@ void z80_memory_w(unsigned int address, unsigned char data)
 
     default: /* $8000-$FFFF: 68k bank (32K) */
     {
+      /* average Z80 wait-states when accessing 68k area */
+      Z80.cycles += 3 * 15;
+
       address = zbank | (address & 0x7FFF);
       if (zbank_memory_map[address >> 16].write)
       {
diff --git a/core/memz80.h b/core/memz80.h
index fab3f93..8dcb2f8 100644
--- a/core/memz80.h
+++ b/core/memz80.h
@@ -5,7 +5,7 @@
  *  Support for SG-1000, Mark-III, Master System, Game Gear & Mega Drive ports access
  *
  *  Copyright (C) 1998-2003  Charles Mac Donald (original code)
- *  Copyright (C) 2007-2016  Eke-Eke (Genesis Plus GX)
+ *  Copyright (C) 2007-2020  Eke-Eke (Genesis Plus GX)
  *
  *  Redistribution and use of this code or any derivative works are permitted
  *  provided that the following conditions are met: