diff --git a/README.md b/README.md
index 1751e47..05df8f4 100644
--- a/README.md
+++ b/README.md
@@ -1,13 +1,17 @@
 # GameBoy++
+
 ## Limitations and Features
 
 Currently supports 32 KiB roms and MBC1 roms.
-Currently passes [dmg-acid2](https://github.com/mattcurrie/dmg-acid2?tab=readme-ov-file), [blargg's cpu_instrs test](https://github.com/retrio/gb-test-roms/tree/master/cpu_instrs), and the [jsmoo SM83 JSON tests](https://github.com/raddad772/jsmoo-json-tests/tree/main/tests/sm83)
+Currently
+passes [dmg-acid2](https://github.com/mattcurrie/dmg-acid2?tab=readme-ov-file), [blargg's cpu_instrs test](https://github.com/retrio/gb-test-roms/tree/master/cpu_instrs),
+and the [jsmoo SM83 JSON tests](https://github.com/raddad772/jsmoo-json-tests/tree/main/tests/sm83)
 
 Tested running Super Mario Land, Dr Mario and Tetris.
-Does not currently support MBC3 (needed for games like Pokemon) or loading saves. Some MBC1 games have issues still.
+Does not currently support MBC3 (needed for games like english versions of Pokemon Red and Blue) or loading saves.
 
 ## Building
+
 `mkdir build && cd build`
 
 `cmake ..`
@@ -15,13 +19,13 @@ Does not currently support MBC3 (needed for games like Pokemon) or loading saves
 `./GameBoy++ <bios> <rom>`
 
 ## Controls
+
 WASD is mapped to the d-pad
 
 K and L are mapped to A and B
 
 O and P are mapped to select and start
 
-
 H enters and exits debug mode
 
 N steps through one instruction
diff --git a/src/mbc.cpp b/src/mbc.cpp
index 728b834..50c3ae3 100644
--- a/src/mbc.cpp
+++ b/src/mbc.cpp
@@ -68,16 +68,37 @@ Byte* AddressSpace::MBCRead(const Word address) {
 }
 
 void AddressSpace::MBCUpdate() {
+	//TODO: multicart roms need to be able to switch the first rom bank as well
+	//see: https://gbdev.io/pandocs/MBC1.html
 	if (MBC == MBC1) {
-		//TODO: multicart roms need to be able to switch the first rom bank as well
-		//see: https://gbdev.io/pandocs/MBC1.html
-
 		//Selected ROM Bank = (Secondary Bank << 5) + ROM Bank
 		romBankRegister &= 0x1F;
 		twoBitBankRegister &= 0x3;
 
 		//512 KiB can only have 8KiB of ram
-		if (romSize > 524288) {
+		if (romSize >= 524288) {
+			if (romBankRegister == 0)
+				selectedRomBank = (twoBitBankRegister << 5) + 1;
+			selectedRomBank = (twoBitBankRegister << 5) + romBankRegister;
+		}
+		else {
+			if (romBankRegister == 0)
+				selectedRomBank = 1;
+			else
+				selectedRomBank = romBankRegister;
+		}
+		selectedExternalRamBank = 0;
+
+		loadRomBank();
+		loadRamBank();
+	}
+	if (MBC == MBC1Ram || MBC == MBC1RamBattery) {
+		//Selected ROM Bank = (Secondary Bank << 5) + ROM Bank
+		romBankRegister &= 0x1F;
+		twoBitBankRegister &= 0x3;
+
+		//512 KiB can only have 8KiB of ram
+		if (romSize >= 524288) {
 			if (romBankRegister == 0)
 				selectedRomBank = (twoBitBankRegister << 5) + 1;
 			selectedRomBank = (twoBitBankRegister << 5) + romBankRegister;
@@ -93,7 +114,6 @@ void AddressSpace::MBCUpdate() {
 		loadRomBank();
 		loadRamBank();
 	}
-	if (MBC == MBC1Ram || MBC == MBC1RamBattery) {}
 }
 
 void AddressSpace::loadRomBank() {