From 83fab4c638c77ccf153d25560417ea506608fa69 Mon Sep 17 00:00:00 2001
From: Logan McNaughton <848146+loganmc10@users.noreply.github.com>
Date: Thu, 16 Apr 2026 12:38:45 +0200
Subject: [PATCH] MBC30 support (#757)

---
 src/device/controller/gbcart.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/device/controller/gbcart.rs b/src/device/controller/gbcart.rs
index 414b3a2..b559683 100644
--- a/src/device/controller/gbcart.rs
+++ b/src/device/controller/gbcart.rs
@@ -110,7 +110,7 @@ fn write_mbc3(
     if address < 0x2000 {
         cart.ram_enabled = value & 0xf == 0xa;
     } else if address < 0x4000 {
-        let bank = value & if cart.ram.len() > 32768 { 0xff } else { 0x7f };
+        let bank = value & if cart.rom.len() > 2097152 { 0xff } else { 0x7f };
         cart.rom_bank = bank as u32;
         if cart.rom_bank == 0 {
             cart.rom_bank = 1;
@@ -182,7 +182,7 @@ fn read_mbc3(
             return;
         }
         if cart.ram_bank < 0x8 {
-            if cart.ram_bank > 3 {
+            if cart.ram_bank > 3 && cart.ram.len() <= 32768 {
                 for i in 0..size {
                     pif_ram[data + i] = 0;
                 }