From 724153e5efd45d8886c504691a2456fb697abf27 Mon Sep 17 00:00:00 2001
From: Lior Halphon <LIJI32@gmail.com>
Date: Fri, 24 Feb 2017 15:14:47 +0200
Subject: [PATCH] Minimal attempt to be compatible with ROMs without correct
 headers

---
 Core/mbc.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Core/mbc.c b/Core/mbc.c
index c8690d1..850d0be 100644
--- a/Core/mbc.c
+++ b/Core/mbc.c
@@ -109,8 +109,12 @@ void GB_update_mbc_mappings(GB_gameboy_t *gb)
 void GB_configure_cart(GB_gameboy_t *gb)
 {
     gb->cartridge_type = &GB_cart_defs[gb->rom[0x147]];
-
-    if (gb->rom[0x147] != 0 && memcmp(gb->cartridge_type, &GB_cart_defs[0], sizeof(GB_cart_defs[0])) == 0) {
+    
+    if (gb->rom[0x147] == 0 && gb->rom_size > 0x8000) {
+        GB_log(gb, "ROM header reports no MBC, but file size is over 32Kb. Assuming cartridge uses MBC3.\n");
+        gb->cartridge_type = &GB_cart_defs[0x11];
+    }
+    else if (gb->rom[0x147] != 0 && memcmp(gb->cartridge_type, &GB_cart_defs[0], sizeof(GB_cart_defs[0])) == 0) {
         GB_log(gb, "Cartridge type %02x is not yet supported.\n", gb->rom[0x147]);
     }