From f86a9afc772f7b1f6705ca1a6e74fd1a536691d7 Mon Sep 17 00:00:00 2001
From: ekeeke <ekeeke31@gmail.com>
Date: Sun, 12 Jul 2020 16:48:53 +0200
Subject: [PATCH] [Core/CD] fixed loading issue when backup RAM cart is filled
 with non-zero data

---
 core/cd_hw/cd_cart.h |  3 ++-
 core/genesis.c       | 14 +++++++++++---
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/core/cd_hw/cd_cart.h b/core/cd_hw/cd_cart.h
index 8a21ba23..6ee7cad2 100644
--- a/core/cd_hw/cd_cart.h
+++ b/core/cd_hw/cd_cart.h
@@ -40,7 +40,8 @@
  /* CD compatible ROM/RAM cartridge */
 typedef struct 
 {
-  uint8 area[0x840080];  /* cartridge ROM/RAM area (max. 8MB ROM + 64KB backup memory + Pro Action Replay 128KB ROM / 64KB RAM + cartridge infos) */
+  uint8 reserved[0x80];  /* reserved for ROM cartridge infos (see md_cart.h) */
+  uint8 area[0x840000];  /* cartridge ROM/RAM area (max. 8MB ROM + 64KB backup memory + Pro Action Replay 128KB ROM / 64KB RAM) */
   uint8 boot;            /* cartridge boot mode (0x00: boot from CD with ROM/RAM cartridge enabled, 0x40: boot from ROM cartridge with CD enabled) */
   uint8 id;              /* RAM cartridge ID (related to RAM size, 0 if disabled) */
   uint8 prot;            /* RAM cartridge write protection */
diff --git a/core/genesis.c b/core/genesis.c
index 1d5d2726..2a069e7e 100644
--- a/core/genesis.c
+++ b/core/genesis.c
@@ -279,10 +279,18 @@ void gen_reset(int hard_reset)
         /* reset CD hardware */
         scd_reset(1);
       }
+
+      /* reset MD cartridge hardware (only when booting from cartridge) */
+      if (scd.cartridge.boot)
+      {
+        md_cart_reset(hard_reset);
+      }
+    }
+    else
+    {
+      /* reset MD cartridge hardware */
+      md_cart_reset(hard_reset);
     }
-    
-    /* reset MD cartridge hardware */
-    md_cart_reset(hard_reset);
 
     /* Z80 bus is released & Z80 is reseted */
     m68k.memory_map[0xa0].read8   = m68k_read_bus_8;