35 lines
894 B
Rust
35 lines
894 B
Rust
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use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
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const VIDEO_RAM_SIZE: usize = 128 * 1024;
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const WORK_RAM_SIZE: usize = 256 * 1024;
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const INTERNAL_RAM: usize = 32 * 1024;
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const PALETTE_AM_SIZE: usize = 1 * 1024;
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const OAM_SIZE: usize = 1 * 1024;
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const BIOS_SIZE: usize = 16 * 1024;
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const GAMEPAK_ROM_SIZE: usize = 32 * 1024 * 1024;
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#[derive(Debug)]
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pub struct SysBus {
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bios_rom: Vec<u8>,
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}
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impl SysBus {
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pub fn new(bios_rom: Vec<u8>) -> SysBus {
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SysBus { bios_rom: bios_rom }
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}
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pub fn read_32(&self, addr: u32) -> u32 {
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let addr = addr as usize;
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(&self.bios_rom[addr..addr + 4])
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.read_u32::<LittleEndian>()
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.unwrap()
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}
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pub fn read_16(&self, addr: u32) -> u16 {
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let addr = addr as usize;
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(&self.bios_rom[addr..addr + 4])
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.read_u16::<LittleEndian>()
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.unwrap()
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}
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}
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