From 117f584b3f3d7945732a29848eb6d4ead1f57bee Mon Sep 17 00:00:00 2001 From: Hannes Schulze Date: Mon, 27 Jan 2025 13:34:21 +0100 Subject: refactor iNES parser --- lib/nes/cartridge.hh | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'lib/nes/cartridge.hh') diff --git a/lib/nes/cartridge.hh b/lib/nes/cartridge.hh index 13c3594..fb75946 100644 --- a/lib/nes/cartridge.hh +++ b/lib/nes/cartridge.hh @@ -19,6 +19,34 @@ namespace nes static constexpr auto prg_rom_bank_size = std::size_t{ 16 * 1024 }; static constexpr auto chr_rom_bank_size = std::size_t{ 8 * 1024 }; static constexpr auto ram_bank_size = std::size_t{ 8 * 1024 }; + static constexpr auto header_length = std::size_t{ 16 }; + + struct header + { + auto get_magic_0() const -> std::uint8_t { return value[0]; } + auto get_magic_1() const -> std::uint8_t { return value[1]; } + auto get_magic_2() const -> std::uint8_t { return value[2]; } + auto get_magic_3() const -> std::uint8_t { return value[3]; } + auto get_prg_rom_banks() const -> unsigned { return value[4]; } + auto get_chr_rom_banks() const -> unsigned { return value[5]; } + auto get_control_1() const -> std::uint8_t { return value[6]; } + auto get_control_2() const -> std::uint8_t { return value[7]; } + auto get_ram_banks() const -> unsigned { return value[8]; } + auto get_has_trainer() const -> bool { return get_control_1() & 0b00000100; } + auto get_mapper_low() const -> unsigned { return (get_control_1() & 0b11110000) >> 4; } + auto get_mapper_high() const -> unsigned { return (get_control_2() & 0b11110000) >> 0; } + auto get_name_table_arrangement() const -> name_table_arrangement { return static_cast((get_control_1() & 0b00000001) >> 0); } + + std::uint8_t value[header_length]{}; + + explicit header(std::uint8_t const* v) + { + for (auto i = std::size_t{ 0 }; i < header_length; ++i) + { + value[i] = v[i]; + } + } + }; status status_{ status::error_uninitialized }; std::vector prg_rom_; -- cgit v1.3.1