MBC5

src/mbc/mbc5.rs

@@ -0,0 +1,58 @@
+use crate::mbc::mode::MBC;
+use crate::memory::Memory;
+
+pub struct MBC5 {
+    rom: Vec<u8>,
+    ram: Vec<u8>,
+    ram_enabled: bool,
+    rom_bank: usize,
+    ram_bank: usize
+}
+
+impl Memory for MBC5 {
+    fn read(&self, a: u16) -> u8 {
+        match a {
+            0x0000..=0x3FFF => self.rom[a as usize],
+            0x4000..=0x7FFF => self.rom[a as usize + self.rom_bank * 0x4000 - 0x4000],
+            0xA000..=0xBFFF => {
+                if self.ram_enabled {
+                    self.ram[a as usize + self.ram_bank * 0x2000 - 0xA000]
+                } else {
+                    0x00
+                }
+            }
+            _ => panic!("Read to unsupported MBC5 address ({:#06x})!", a),
+        }
+    }
+
+    fn write(&mut self, a: u16, v: u8) {
+        match a {
+            0x0000..=0x1FFF => self.ram_enabled = v & 0x0F == 0x0A,
+            0x2000..=0x2FFF => self.rom_bank = (self.rom_bank & 0x100) | (v as usize),
+            0x3000..=0x3FFF => self.rom_bank = (self.rom_bank & 0x0ff) | (((v & 0x01) as usize) << 8),
+            0x4000..=0x5FFF => self.ram_bank = (v & 0x0f) as usize,
+            // Unknown writes
+            0x6000..=0x7FFF => {},
+            0xA000..=0xBFFF => {
+                if self.ram_enabled {
+                    self.ram[a as usize + self.ram_bank * 0x2000 - 0xA000] = v;
+                }
+            }
+            _ => panic!("Write to unsupported MBC5 address ({:#06x})!", a),
+        }
+    }
+}
+
+impl MBC for MBC5 { }
+
+impl MBC5 {
+    pub fn new(rom: Vec<u8>) -> Self {
+        Self {
+            rom,
+            ram: vec![0x00; 131072],
+            ram_enabled: false,
+            rom_bank: 0x00,
+            ram_bank: 0x00
+        }
+    }
+}

src/mbc/mod.rs

@@ -1,4 +1,5 @@
 pub mod mode;
 pub mod rom_only;
 pub mod mbc1;
-pub mod mbc3;
+pub mod mbc3;
+pub mod mbc5;

src/mmu.rs

@@ -3,6 +3,7 @@ use crate::mbc::mode::{MBC, MBCMode};
 use crate::mbc::rom_only::ROMOnly;
 use crate::mbc::mbc1::MBC1;
 use crate::mbc::mbc3::MBC3;
+use crate::mbc::mbc5::MBC5;
 use crate::memory::Memory;
 use crate::ppu::PPU;
 use crate::timer::Timer;
@@ -38,6 +39,7 @@ impl MMU {
             MBCMode::RomOnly => Box::new(ROMOnly::new(rom)),
             MBCMode::MBC1 => Box::new(MBC1::new(rom)),
             MBCMode::MBC3 => Box::new(MBC3::new(rom)),
+            MBCMode::MBC5 => Box::new(MBC5::new(rom)),
             v => panic!("Unsupported MBC type! {:}", v)
         };