diff options
| -rw-r--r-- | src/cartridge.rs | 10 | ||||
| -rw-r--r-- | src/lib.rs | 2 | ||||
| -rw-r--r-- | src/main.rs | 4 | ||||
| -rw-r--r-- | src/mapper.rs | 55 | ||||
| -rw-r--r-- | src/memory.rs | 2 |
5 files changed, 71 insertions, 2 deletions
diff --git a/src/cartridge.rs b/src/cartridge.rs new file mode 100644 index 0000000..28928c0 --- /dev/null +++ b/src/cartridge.rs @@ -0,0 +1,10 @@ +pub enum BankType { + PRG_ROM, /* program rom */ + CHR_ROM, /* pattern rom */ + SRAM, /* save ram */ +} + +pub trait Cartridge { + fn get_bank_num(&self, kind: BankType) -> usize; + fn get_bank(&self, idx: usize, kind: BankType) -> *mut [u8]; +} @@ -2,3 +2,5 @@ extern crate core; mod memory; mod mos6502; mod ppu; +mod cartridge; +mod mapper; diff --git a/src/main.rs b/src/main.rs index e429932..4a963b6 100644 --- a/src/main.rs +++ b/src/main.rs @@ -1,7 +1,9 @@ extern crate core; mod memory; -mod ppu; mod mos6502; +mod ppu; +mod cartridge; +mod mapper; fn main() { /* let code = [0xa9, 0x01, 0x8d, 0x00, 0x02, 0xa9, 0x05, 0x8d, 0x01, 0x02, 0xa9, 0x08, 0x8d, 0x02, 0x02 ]; diff --git a/src/mapper.rs b/src/mapper.rs new file mode 100644 index 0000000..d83157a --- /dev/null +++ b/src/mapper.rs @@ -0,0 +1,55 @@ +use memory::VMem; +use cartridge::{Cartridge, BankType}; +pub struct Mapper2<'a, T: 'a> where T: Cartridge { + cart: &'a T, + prg_bank1: &'a [u8], + prg_bank2: &'a [u8], + chr_bank: &'a mut [u8], + sram: &'a mut [u8], + bank_num: usize +} + +impl<'a, T> VMem for Mapper2<'a, T> where T: Cartridge { + fn read(&self, addr: u16) -> u8 { + let addr = addr as usize; + if addr < 0x2000 { + self.chr_bank[addr] + } else if addr >= 0xc000 { + self.prg_bank2[addr - 0xc000] + } else if addr >= 0x8000 { + self.prg_bank1[addr - 0x8000] + } else if addr >= 0x6000 { + self.sram[addr - 0x6000] + } else { + panic!("unmapped address: 0x{:04x}", addr) + } + } + + fn write(&mut self, addr: u16, data: u8) { + let addr = addr as usize; + if addr < 0x2000 { + self.chr_bank[addr] = data; + } else if addr >= 0x8000 { + self.prg_bank1 = unsafe {&*self.cart.get_bank( + data as usize % self.bank_num, BankType::PRG_ROM)}; + } else if addr >= 0x6000 { + self.sram[addr - 0x6000] = data; + } else { + panic!("invalid write to address: 0x{:04x}", addr); + } + } +} + +impl<'a, T> Mapper2<'a, T> where T: Cartridge { + fn new(cart: &'a mut T) -> Self { + let bank_num = cart.get_bank_num(BankType::PRG_ROM); + unsafe { + Mapper2{cart, + prg_bank1: &*cart.get_bank(0, BankType::PRG_ROM), + prg_bank2: &*cart.get_bank(bank_num - 1, BankType::PRG_ROM), + chr_bank: &mut *cart.get_bank(0, BankType::CHR_ROM), + sram: &mut *cart.get_bank(0, BankType::SRAM), + bank_num} + } + } +} diff --git a/src/memory.rs b/src/memory.rs index 386e859..852b837 100644 --- a/src/memory.rs +++ b/src/memory.rs @@ -13,7 +13,7 @@ impl CPUMemory { } } -impl VMem for CPUMemory { +impl<'a> VMem for CPUMemory { fn read(&self, addr: u16) -> u8 { if addr < 0x2000 { self.internal[(addr & 0x07ff) as usize] |