reznez 0.0.0

The high accuracy NES Emulator
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37

use crate::memory::mapper::*;

const PRG_WINDOWS: PrgLayout = PrgLayout::new(&[
    PrgWindow::new(0x6000, 0x7FFF,  8 * KIBIBYTE, Bank::EMPTY),
    PrgWindow::new(0x8000, 0xBFFF, 16 * KIBIBYTE, Bank::switchable_rom(P0)),
    PrgWindow::new(0xC000, 0xFFFF, 16 * KIBIBYTE, Bank::fixed_rom(BankIndex::LAST)),
]);

const CHR_WINDOWS: ChrLayout = ChrLayout::new(&[
    ChrWindow::new(0x0000, 0x1FFF, 8 * KIBIBYTE, Bank::fixed_rom(BankIndex::FIRST)),
]);

// UxROM, but the register is shifted by two bits.
pub struct Mapper094;

impl Mapper for Mapper094 {
    fn initial_layout(&self) -> InitialLayout {
        InitialLayout::builder()
            .prg_max_bank_count(8)
            .prg_bank_size(16 * KIBIBYTE)
            .prg_windows(PRG_WINDOWS)
            .chr_max_bank_count(1)
            .chr_bank_size(8 * KIBIBYTE)
            .chr_windows(CHR_WINDOWS)
            .name_table_mirroring_source(NameTableMirroringSource::Cartridge)
            .build()
    }

    fn write_to_cartridge_space(&mut self, params: &mut MapperParams, address: CpuAddress, value: u8) {
        match address.to_raw() {
            0x0000..=0x401F => unreachable!(),
            0x4020..=0x7FFF => { /* Do nothing. */ }
            0x8000..=0xFFFF => params.set_bank_register(P0, splitbits_named!(value, "...ppp..")),
        }
    }
}