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Diffstat (limited to 'lib/nes/ref/mapper.cc')
| -rw-r--r-- | lib/nes/ref/mapper.cc | 134 |
1 files changed, 0 insertions, 134 deletions
diff --git a/lib/nes/ref/mapper.cc b/lib/nes/ref/mapper.cc deleted file mode 100644 index 7e4cffe..0000000 --- a/lib/nes/ref/mapper.cc +++ /dev/null @@ -1,134 +0,0 @@ -#include "nes/ref/mapper.hh" -#include "nes/ref/cartridge.hh" -#include <iostream> - -namespace nes::ref -{ - mapper::mapper( - cartridge& cartridge, - read_cpu_func const read_cpu, write_cpu_func const write_cpu, - read_ppu_func const read_ppu, write_ppu_func const write_ppu) - : cartridge_{ cartridge } - , read_cpu_{ read_cpu } - , write_cpu_{ write_cpu } - , read_ppu_{ read_ppu } - , write_ppu_{ write_ppu } - { - } - - auto mapper::select(cartridge& cartridge) -> mapper - { - switch (cartridge.get_mapper_number()) - { - case 0x00: - return mapper{ - cartridge, - &mapper::nrom_read_cpu, &mapper::nrom_write_cpu, - &mapper::nrom_read_ppu, &mapper::nrom_write_ppu }; - default: - std::cerr << "Mapper not implemented: " << std::hex << cartridge.get_mapper_number() << std::endl; - std::abort(); - } - } - - // ----------------------------------------------------------------------------------------------------------------- - // NROM - // ----------------------------------------------------------------------------------------------------------------- - - auto mapper::nrom_read_cpu(address const addr) -> std::uint8_t - { - if (addr <= address{ 0x5FFF }) - { - return 0x0; - } - if (addr <= address{ 0x7FFF }) - { - return cartridge_.get_ram()[addr.get_absolute() - 0x6000]; - } - if (addr <= address{ 0xBFFF }) - { - auto const rel = addr.get_absolute() - 0x8000; - if (rel >= cartridge_.get_prg_rom_length()) { return 0x0; } - - return cartridge_.get_prg_rom()[rel]; - } - if (addr <= address{ 0xFFFF }) - { - auto rel = addr.get_absolute() - 0xC000; - if (cartridge_.get_prg_rom_length() > 0x4000) { rel += 0x4000; } - if (rel >= cartridge_.get_prg_rom_length()) { return 0x0; } - - return cartridge_.get_prg_rom()[rel]; - } - - return 0x0; - } - - auto mapper::nrom_write_cpu(address const addr, std::uint8_t const value) -> void - { - if (addr <= address{ 0x5FFF }) - { - return; - } - if (addr <= address{ 0x7FFF }) - { - cartridge_.get_ram_mut()[addr.get_absolute() - 0x6000] = value; - return; - } - } - - auto mapper::nrom_read_ppu(address const addr, std::uint8_t const* vram) -> std::uint8_t - { - if (addr <= address{ 0x1FFF }) - { - auto const rel = addr.get_absolute(); - if (rel >= cartridge_.get_chr_rom_length()) { return 0x0; } - - return cartridge_.get_chr_rom()[rel]; - } - if (addr <= address{ 0x3EFF }) - { - return vram[nrom_mirrored_vram_address(addr)]; - } - - return 0x0; - } - - auto mapper::nrom_write_ppu(address const addr, std::uint8_t* vram, std::uint8_t const value) -> void - { - if (addr <= address{ 0x1FFF }) - { - return; - } - if (addr <= address{ 0x3EFF }) - { - vram[nrom_mirrored_vram_address(addr)] = value; - return; - } - } - - auto mapper::nrom_mirrored_vram_address(address const addr) const -> unsigned - { - auto const rel = addr.get_absolute() % 0x1000; - - switch (cartridge_.get_name_table_arrangement()) - { - case name_table_arrangement::horizontal: - // $2000 = $2400, $2800 = $2c00 - if (rel <= 0x3FF) { return 0x000 + (rel % 0x400); } - if (rel <= 0x7FF) { return 0x000 + (rel % 0x400); } - if (rel <= 0xBFF) { return 0x400 + (rel % 0x400); } - if (rel <= 0xFFF) { return 0x400 + (rel % 0x400); } - break; - case name_table_arrangement::vertical: - // $2000 = $2800, $2400 = $2c00 - if (rel <= 0x3FF) { return 0x000 + (rel % 0x400); } - if (rel <= 0x7FF) { return 0x400 + (rel % 0x400); } - if (rel <= 0xBFF) { return 0x000 + (rel % 0x400); } - if (rel <= 0xFFF) { return 0x400 + (rel % 0x400); } - break; - } - - return 0; - } -} // namespace nes::ref
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