From e822f17bb72c36ee7efed439b414e43deebd18dc Mon Sep 17 00:00:00 2001
From: Lior Halphon <LIJI32@gmail.com>
Date: Wed, 30 Mar 2016 23:33:32 +0300
Subject: [PATCH] =?UTF-8?q?Wrapping=20external=20RAM=20banking=20support.?=
 =?UTF-8?q?=20Required=20for=20Pok=C3=A9mon=20Pinball's=20saves.?=
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---
 Core/memory.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Core/memory.c b/Core/memory.c
index 30a366ed..459bf769 100644
--- a/Core/memory.c
+++ b/Core/memory.c
@@ -234,6 +234,10 @@ static void write_mbc(GB_gameboy_t *gb, unsigned short addr, unsigned char value
             }
             else {
                 gb->mbc_ram_bank = value;
+                /* Some games assume banks wrap around. We can do this if RAM size is a power of two */
+                if (gb->mbc_ram_bank >= gb->mbc_ram_size / 0x2000 && (gb->mbc_ram_size & (gb->mbc_ram_size - 1)) == 0 && gb->mbc_ram_size != 0) {
+                    gb->mbc_ram_bank %= gb->mbc_ram_size / 0x2000;
+                }
             }
             break;
         case 6: