initial upload
This commit is contained in:
5
.gitignore
vendored
Normal file
5
.gitignore
vendored
Normal file
@@ -0,0 +1,5 @@
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cmake-build-debug/
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.idea
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roms/
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bootrom.bin
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10
CMakeLists.txt
Normal file
10
CMakeLists.txt
Normal file
@@ -0,0 +1,10 @@
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cmake_minimum_required(VERSION 3.25)
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project(GBpp)
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set(CMAKE_CXX_STANDARD 23)
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find_package(SDL2 REQUIRED)
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include_directories(${SDL2_INCLUDE_DIRS})
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add_executable(GBpp src/main.cpp src/gameboy.cpp src/opcode.cpp
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src/interupts.cpp src/ppu.cpp)
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target_link_libraries(GBpp ${SDL2_LIBRARIES})
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51
src/defines.hpp
Normal file
51
src/defines.hpp
Normal file
@@ -0,0 +1,51 @@
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#ifndef GBPP_SRC_DEFINES_HPP_
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#define GBPP_SRC_DEFINES_HPP_
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#define Word uint16_t
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#define Byte uint8_t
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// Bit Name Set Clr Expl.
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// 7 zf Z NZ Zero Flag
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// 6 n - - Add/Sub-Flag (BCD)
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// 5 h - - Half Carry Flag (BCD)
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// 4 cy C NC Carry Flag
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// 3-0 - - - Not used (always zero)
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#define CARRY_FLAG 4 //'C'
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#define HALFCARRY_FLAG 5 //'H'
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#define SUBTRACT_FLAG 6 //'N'
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#define ZERO_FLAG 7 //'Z'
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#define VBLANK_INTERRUPT 0
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#define LCD_STAT_INTERRUPT 1
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#define TIMER_INTERRUPT 2
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#define SERIAL_INTERRUPT 3
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#define JOYPAD_INTERRUPT 4
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#define T_CLOCK_FREQ 4194304
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#define DIVIDER_REGISTER_FREQ 16384
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#define BOOTROM_SIZE 0x100
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#define RESOLUTION_X 160
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#define RESOLUTION_Y 144
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#define SCREEN_BPP 3
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#define ROM_BANK_SIZE 0x4000
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#define SCANLINES_PER_FRAME 154
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#define SCANLINE_DURATION 456
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#define FRAME_DURATION 70224
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#define MODE2_DURATION 80
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#define MODE3_BASE_DURATION 168
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#define MODE0_3_DURATION 376 //mode3 is 168 to 291, mode0 85 to 208
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#define MODE1_DURATION 4560
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#define H_SYNC 9198
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#define V_SYNC 59.73
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#define HBlank_DURATION 204 //GPU_MODE 0
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#define SCANLINE_OAM_FREQ 80 //GPU_MODE 2
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#define SCANLINE_VRAM_FREQ 80 //GPU_MODE 3
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#endif
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94
src/gameboy.cpp
Normal file
94
src/gameboy.cpp
Normal file
@@ -0,0 +1,94 @@
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#include <iostream>
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#include "gameboy.hpp"
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bool AddressSpace::getBootromState()
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{
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return bootromLoaded;
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}
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void AddressSpace::unmapBootrom()
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{
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bootromLoaded = false;
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}
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void AddressSpace::mapBootrom()
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{
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bootromLoaded = true;
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}
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void AddressSpace::loadBootrom(std::string filename)
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{
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std::ifstream file;
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int size = std::filesystem::file_size(filename);
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if(size != 256)
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{
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std::cerr << "Bootrom was an unexpected size!\nQuitting!\n" << std::endl;
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exit(1);
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}
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file.open(filename, std::ios::binary);
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file.read(reinterpret_cast<char *>(bootrom), BOOTROM_SIZE);
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}
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void AddressSpace::loadGame(std::string filename)
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{
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game.open(filename, std::ios::binary);
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if(!game.is_open())
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{
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std::cerr << "Game was not found!\nQuitting!\n" << std::endl;
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exit(1);
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}
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game.read(reinterpret_cast<char *>(memoryLayout.romBank1), ROM_BANK_SIZE*2);
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}
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void GameBoy::addCycles(uint8_t ticks)
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{
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cycles = (cycles+ticks) % T_CLOCK_FREQ;
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lastOpTicks = ticks;
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}
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void test()
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{
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printf("");
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}
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void GameBoy::start(std::string bootrom, std::string game)
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{
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addressSpace.loadBootrom(bootrom);
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addressSpace.loadGame(game);
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bool quit = false;
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while(!quit)
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{
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// Event loop: Check and handle SDL events
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// if(SDL_PollEvent(&event))
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// {
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// if(event.type == SDL_QUIT)
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// {
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// quit = true; // Set the quit flag when the close button is hit
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// }
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// }
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opcodeHandler();
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interruptHandler();
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//timing();
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ppuUpdate();
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if(PC == 0x8c && DE.hi == 0)
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test();
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if(PC > 0xFF && addressSpace.getBootromState())
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{
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addressSpace.unmapBootrom();
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}
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if(PC > 0x2FF)
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{
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test();
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}
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int cyclesSince = cyclesSinceLastRefresh();
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if(cyclesSince > FRAME_DURATION)
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{
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lastRefresh = cycles;
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SDL2present();
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}
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}
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}
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277
src/gameboy.hpp
Normal file
277
src/gameboy.hpp
Normal file
@@ -0,0 +1,277 @@
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#ifndef GBPP_SRC_GAMEBOY_HPP_
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#define GBPP_SRC_GAMEBOY_HPP_
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#include <filesystem>
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#include <cstdint>
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#include <cstring>
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#include <string>
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#include <fstream>
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#include <vector>
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#include <SDL.h>
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#include "defines.hpp"
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//two bits per colour
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enum Colour
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{
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black = 0b11,
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darkGray = 0b10,
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lightGray = 0b01,
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white = 0b00
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};
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enum PPUMode
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{
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mode0, // Horizontal Blank (Mode 0): No access to video RAM, occurs during horizontal blanking period.
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mode1, // Vertical Blank (Mode 1): No access to video RAM, occurs during vertical blanking period.
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mode2, // OAM Search (Mode 2): Access to OAM (Object Attribute Memory) only, sprite evaluation.
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mode3 // Pixel Transfer (Mode 3): Access to both OAM and video RAM, actual pixel transfer to the screen.
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};
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union RegisterPair
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{
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Word reg; //register.reg == (hi << 8) + lo. (hi is more significant than lo)
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struct
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{
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Byte lo;
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Byte hi;
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};
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};
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class AddressSpace
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{
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private:
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bool bootromLoaded = true;
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Byte bootrom[BOOTROM_SIZE];
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std::ifstream game;
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public:
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AddressSpace()
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{
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// Initialize the memory to zero
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memoryLayout = {};
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std::memset(memoryLayout.memory, 0, sizeof(memoryLayout.memory));
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}
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// Nested union for the memory layout
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union MemoryLayout
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{
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Byte memory[0x10000];
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struct
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{
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Byte romBank1[ROM_BANK_SIZE]; // Mapped to 0x0000
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Byte romBankSwitch[ROM_BANK_SIZE]; // Mapped to 0x4000
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Byte vram[0x2000]; // Mapped to 0x8000
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Byte externalRam[0x2000]; // Mapped to 0xA000
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Byte memoryBank1[0x1000]; // Mapped to 0xC000
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Byte memoryBank2[0x1000]; // Mapped to 0xD000
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Byte echoRam[0x1E00]; // Mapped to 0xE000 (Echo RAM, mirrors 0xC000 to 0xDFFF)
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Byte spriteAttributeTable[0xA0]; // Mapped to 0xFE00
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Byte notUsable[0x60]; // Mapped to 0xFEA0
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Byte io[0x80]; // Mapped to 0xFF00, 0xFF0F is interrupt flag
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Byte specialRam[0x7F]; // Mapped to 0xFF80
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Byte interuptEnableReg; // Mapped to 0xFFFF
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};
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} memoryLayout;
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bool getBootromState();
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void unmapBootrom();
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void mapBootrom();
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void loadBootrom(std::string filename);
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void loadGame(std::string filename);
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//overload [] for echo ram and bootrom support
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Byte operator[](uint32_t address) const
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{
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if(address >= 0xE000 && address < 0xFE00)
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return memoryLayout.echoRam[address - 0xE000];
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if(address < 0x0100 && bootromLoaded)
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return bootrom[address];
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else
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return memoryLayout.memory[address];
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}
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Byte& operator[](uint32_t address)
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{
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if(address >= 0xE000 && address < 0xFE00)
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return memoryLayout.echoRam[address - 0xE000];
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if(address < 0x0100 && bootromLoaded)
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return bootrom[address];
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else
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return memoryLayout.memory[address];
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}
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};
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class GameBoy {
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private:
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uint32_t cycles = 0;
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uint32_t lastOpTicks = 0;
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uint32_t lastRefresh = 0;
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uint32_t lastScanline = 0;
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uint32_t cyclesToStayInHblank = -1;
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uint8_t IME = 0; //enables interupts
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//Accumulator and flags
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RegisterPair AF;
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//General purpose CPU registers
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RegisterPair BC;
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RegisterPair DE;
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RegisterPair HL;
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Word SP = 0xFFFE; //stack pointer
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Word PC = 0x0000; //program counter
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AddressSpace addressSpace;
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//General purpose hardware registers
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Byte* JOYP = &addressSpace[0xFF00];
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Byte* SB = &addressSpace[0xFF01];
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Byte* SC = &addressSpace[0xFF02];
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Byte* DIV = &addressSpace[0xFF04];
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//Timer registers
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Byte* TIMA = &addressSpace[0xFF05];
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Byte* TMA = &addressSpace[0xFF15]; //unused
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Byte* TAC = &addressSpace[0xFF16];
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//interrupt flag and enable
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Byte* IF = &addressSpace[0xFF0F];
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Byte* IE = &addressSpace[0xFFFF];
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//Sound registers
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Byte* NR10 = &addressSpace[0xFF10];
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Byte* NR11 = &addressSpace[0xFF11];
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Byte* NR12 = &addressSpace[0xFF12];
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Byte* NR13 = &addressSpace[0xFF13];
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Byte* NR14 = &addressSpace[0xFF14];
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Byte* NR20 = &addressSpace[0xFF15]; //unused
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Byte* NR21 = &addressSpace[0xFF16];
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Byte* NR22 = &addressSpace[0xFF17];
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Byte* NR23 = &addressSpace[0xFF18];
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Byte* NR24 = &addressSpace[0xFF19];
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Byte* NR30 = &addressSpace[0xFF1A];
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Byte* NR31 = &addressSpace[0xFF1B];
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Byte* NR32 = &addressSpace[0xFF1C];
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Byte* NR33 = &addressSpace[0xFF1D];
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Byte* NR34 = &addressSpace[0xFF1E];
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Byte* NR40 = &addressSpace[0xFF1F]; //unused
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Byte* NR41 = &addressSpace[0xFF20];
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Byte* NR42 = &addressSpace[0xFF21];
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Byte* NR43 = &addressSpace[0xFF22];
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Byte* NR44 = &addressSpace[0xFF23];
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Byte* NR50 = &addressSpace[0xFF24];
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Byte* NR51 = &addressSpace[0xFF25];
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Byte* NR52 = &addressSpace[0xFF26];
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Byte* waveRam = &addressSpace[0xFF30]; //WaveRam[0x10]
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|
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//PPU registers
|
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Byte* LCDC = &addressSpace[0xFF40];
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Byte* STAT = &addressSpace[0xFF41];
|
||||
Byte* SCY = &addressSpace[0xFF42];
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||||
Byte* SCX = &addressSpace[0xF43];
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Byte* LY = &addressSpace[0xFF44];
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||||
Byte* LYC = &addressSpace[0xFF45];
|
||||
Byte* DMA = &addressSpace[0xFF46];
|
||||
Byte* BGP = &addressSpace[0xFF47];
|
||||
Byte* OBP0 = &addressSpace[0xFF48];
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||||
Byte* OBP1 = &addressSpace[0xFF49];
|
||||
Byte* WY = &addressSpace[0xFF4A];
|
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Byte* WX = &addressSpace[0xFF4B];
|
||||
|
||||
PPUMode currentMode;
|
||||
|
||||
//3 colour channels
|
||||
uint32_t* framebuffer = new uint32_t[RESOLUTION_X*RESOLUTION_Y*SCREEN_BPP];
|
||||
SDL_Window *screen;
|
||||
SDL_Renderer *renderer;
|
||||
SDL_Texture *texture;
|
||||
SDL_Event event;
|
||||
|
||||
void opcodeHandler();
|
||||
void ppuUpdate();
|
||||
void drawLine();
|
||||
void SDL2present();
|
||||
|
||||
void checkPPUMode();
|
||||
void setPPUMode(PPUMode mode);
|
||||
int cyclesSinceLastScanline();
|
||||
int cyclesSinceLastRefresh();
|
||||
|
||||
void interruptHandler();
|
||||
bool testInterruptEnabled(Byte interrupt);
|
||||
void resetInterrupt(Byte interrupt);
|
||||
|
||||
void VBlankHandle();
|
||||
void LCDStatHandle();
|
||||
void timerHandle();
|
||||
void serialHandle();
|
||||
void joypadHandle();
|
||||
|
||||
void setFlag(Byte bit);
|
||||
void resetFlag(Byte bit);
|
||||
bool getFlag(Byte bit) const;
|
||||
|
||||
Word getWordPC();
|
||||
Byte getBytePC();
|
||||
Word getWordSP();
|
||||
Byte getByteSP();
|
||||
|
||||
void addCycles(Byte ticks);
|
||||
|
||||
//OPCODE FUNCTIONS
|
||||
template<typename T>
|
||||
void ld(T& dest, T src);
|
||||
template<typename T>
|
||||
void orBitwise(T &dest, T src);
|
||||
template<typename T>
|
||||
void andBitwise(T &dest, T src);
|
||||
template<typename T>
|
||||
void xorBitwise(T& dest, T src);
|
||||
template<typename T>
|
||||
void bit(T testBit, T reg);
|
||||
template<typename T>
|
||||
void jp(T address);
|
||||
template<typename T>
|
||||
bool jrNZ(T offset);
|
||||
template<typename T>
|
||||
void inc(T& reg);
|
||||
template<typename T>
|
||||
void call(T address);
|
||||
void halt();
|
||||
void stop();
|
||||
template<typename T>
|
||||
void ldW(T dest, T src);
|
||||
template<typename T>
|
||||
void cp(T value);
|
||||
template<typename T>
|
||||
void dec(T& reg);
|
||||
template<typename T>
|
||||
bool jrZ(T offset);
|
||||
template<typename T>
|
||||
void sub(T value);
|
||||
template<typename T>
|
||||
void jr(T OFFSET);
|
||||
template<typename T>
|
||||
void push(T reg);
|
||||
template<typename T>
|
||||
void rl(T& reg);
|
||||
template<typename T>
|
||||
void pop(T& reg);
|
||||
template<typename T>
|
||||
void rla(T& reg);
|
||||
template<typename T>
|
||||
void rst(T address);
|
||||
void ret();
|
||||
template<typename T>
|
||||
void add(T& reg, T value);
|
||||
void cpl();
|
||||
void ccf();
|
||||
void swap(Byte &value);
|
||||
|
||||
public:
|
||||
void start(std::string bootrom, std::string game);
|
||||
void SDL2setup();
|
||||
void SDL2destroy();
|
||||
};
|
||||
|
||||
#endif //GBPP_SRC_GAMEBOY_HPP_
|
||||
78
src/interupts.cpp
Normal file
78
src/interupts.cpp
Normal file
@@ -0,0 +1,78 @@
|
||||
#include "defines.hpp"
|
||||
#include "gameboy.hpp"
|
||||
|
||||
bool GameBoy::testInterruptEnabled(Byte interrupt)
|
||||
{
|
||||
return (*IE) & (Byte) (1 << interrupt);
|
||||
}
|
||||
|
||||
void GameBoy::resetInterrupt(Byte interrupt)
|
||||
{
|
||||
*IF &= ~(1 << interrupt);
|
||||
}
|
||||
|
||||
void GameBoy::interruptHandler()
|
||||
{
|
||||
if(!IME)
|
||||
return;
|
||||
|
||||
if(*IF & (Byte) (1 << VBLANK_INTERRUPT) && testInterruptEnabled(VBLANK_INTERRUPT))
|
||||
VBlankHandle();
|
||||
if(*IF & (Byte) (1 << LCD_STAT_INTERRUPT) && testInterruptEnabled(LCD_STAT_INTERRUPT))
|
||||
LCDStatHandle();
|
||||
if(*IF & (Byte) (1 << TIMER_INTERRUPT) && testInterruptEnabled(TIMER_INTERRUPT))
|
||||
timerHandle();
|
||||
if(*IF & (Byte) (1 << SERIAL_INTERRUPT) && testInterruptEnabled(SERIAL_INTERRUPT))
|
||||
serialHandle();
|
||||
if(*IF & (Byte) (1 << JOYPAD_INTERRUPT) && testInterruptEnabled(JOYPAD_INTERRUPT))
|
||||
joypadHandle();
|
||||
}
|
||||
|
||||
void GameBoy::VBlankHandle()
|
||||
{
|
||||
printf("VBlank interrupt");
|
||||
IME = 0;
|
||||
push(PC);
|
||||
PC = 0x40;
|
||||
resetInterrupt(VBLANK_INTERRUPT);
|
||||
}
|
||||
|
||||
void GameBoy::LCDStatHandle()
|
||||
{
|
||||
printf("LCD stat interrupt");
|
||||
IME = 0;
|
||||
push(PC);
|
||||
addCycles(16);
|
||||
PC = 0x48;
|
||||
resetInterrupt(LCD_STAT_INTERRUPT);
|
||||
}
|
||||
|
||||
void GameBoy::timerHandle()
|
||||
{
|
||||
printf("timer interrupt");
|
||||
IME = 0;
|
||||
push(PC);
|
||||
addCycles(16);
|
||||
PC = 0x50;
|
||||
resetInterrupt(TIMER_INTERRUPT);
|
||||
}
|
||||
|
||||
void GameBoy::serialHandle()
|
||||
{
|
||||
printf("serial interrupt");
|
||||
IME = 0;
|
||||
push(PC);
|
||||
addCycles(16);
|
||||
PC = 0x58;
|
||||
resetInterrupt(SERIAL_INTERRUPT);
|
||||
}
|
||||
|
||||
void GameBoy::joypadHandle()
|
||||
{
|
||||
printf("joypad interrupt");
|
||||
IME = 0;
|
||||
push(PC);
|
||||
addCycles(16);
|
||||
PC = 0x60;
|
||||
resetInterrupt(JOYPAD_INTERRUPT);
|
||||
}
|
||||
18
src/main.cpp
Normal file
18
src/main.cpp
Normal file
@@ -0,0 +1,18 @@
|
||||
#include <iostream>
|
||||
#include <filesystem>
|
||||
#include <string>
|
||||
#include <optional>
|
||||
#include "gameboy.hpp"
|
||||
#include "defines.hpp"
|
||||
|
||||
namespace fs = std::filesystem;
|
||||
|
||||
int main(int argc, char** argv)
|
||||
{
|
||||
auto* gb = new GameBoy();
|
||||
gb->SDL2setup();
|
||||
gb->start("/home/braiden/Code/GBpp/bootrom.bin", "/home/braiden/Code/GBpp/roms/DrMario.gb");
|
||||
gb->SDL2destroy();
|
||||
delete gb;
|
||||
return 0;
|
||||
}
|
||||
212
src/ppu.cpp
Normal file
212
src/ppu.cpp
Normal file
@@ -0,0 +1,212 @@
|
||||
#include "gameboy.hpp"
|
||||
#include "defines.hpp"
|
||||
|
||||
|
||||
|
||||
void GameBoy::ppuUpdate()
|
||||
{
|
||||
//test HBlank
|
||||
checkPPUMode();
|
||||
|
||||
if(cyclesToStayInHblank != -1)
|
||||
{
|
||||
if (cyclesToStayInHblank < cyclesSinceLastScanline())
|
||||
{
|
||||
return;
|
||||
}
|
||||
if(cyclesToStayInHblank >= cyclesSinceLastScanline())
|
||||
{
|
||||
lastScanline = cycles;
|
||||
cyclesToStayInHblank = -1;
|
||||
}
|
||||
}
|
||||
|
||||
// Check the PPU mode (HBlank, VBlank, OAM Search, or Pixel Transfer)
|
||||
Byte mode = (*STAT)&0x03;
|
||||
switch(mode)
|
||||
{
|
||||
case 0:
|
||||
if(cyclesSinceLastScanline() > MODE2_DURATION + MODE3_BASE_DURATION)
|
||||
{
|
||||
drawLine();
|
||||
cyclesToStayInHblank = SCANLINE_DURATION - cyclesSinceLastScanline();
|
||||
lastScanline = cycles;
|
||||
(*LY)++;
|
||||
if((*LY) > 153)
|
||||
(*LY) = 0;
|
||||
}
|
||||
currentMode = PPUMode::mode0;
|
||||
break;
|
||||
|
||||
//vblank
|
||||
case 1:
|
||||
if(currentMode != PPUMode::mode1)
|
||||
{
|
||||
drawLine();
|
||||
}
|
||||
if(cyclesSinceLastScanline() > SCANLINE_DURATION)
|
||||
{
|
||||
lastScanline = cycles;
|
||||
(*LY)++;
|
||||
if((*LY) > 153)
|
||||
(*LY) = 0;
|
||||
}
|
||||
currentMode = PPUMode::mode1;
|
||||
break;
|
||||
case 2:
|
||||
currentMode = PPUMode::mode2;
|
||||
break;
|
||||
case 3:
|
||||
currentMode = PPUMode::mode3;
|
||||
break;
|
||||
}
|
||||
|
||||
if ((*LY) == (*LYC) || (*STAT)&(1 << 6))
|
||||
{
|
||||
// Request STAT interrupt if LY matches LYC
|
||||
//bug on DMG models triggers a STAT interrupt anytime the STAT register is written
|
||||
//Road Rage and Zerd no Denetsu rely on this
|
||||
(*STAT) |= (1 << 2);
|
||||
}
|
||||
|
||||
// Check for STAT interrupts and request if needed (e.g., when entering specific modes)
|
||||
bool hBlankInterruptEnabled = (*STAT)&(1 << 3);
|
||||
bool vBlankInterruptEnabled = (*STAT)&(1 << 4);/* Determine if VBlank interrupt is enabled */
|
||||
bool oamInterruptEnabled = (*STAT)&(1 << 5);/* Determine if OAM Search interrupt is enabled */
|
||||
|
||||
if (currentMode == PPUMode::mode0 && hBlankInterruptEnabled)
|
||||
{
|
||||
// Request HBlank interrupt
|
||||
}
|
||||
else if (currentMode == PPUMode::mode1 && vBlankInterruptEnabled)
|
||||
{
|
||||
// Request VBlank interrupt
|
||||
}
|
||||
else if (currentMode == PPUMode::mode2 && oamInterruptEnabled)
|
||||
{
|
||||
// Request OAM Search interrupt
|
||||
}
|
||||
}
|
||||
|
||||
int GameBoy::cyclesSinceLastScanline()
|
||||
{
|
||||
int difference = cycles - lastScanline;
|
||||
if (difference < 0)
|
||||
{
|
||||
// Handle the case when cycles has wrapped around (overflowed)
|
||||
difference += T_CLOCK_FREQ;
|
||||
}
|
||||
return difference;
|
||||
}
|
||||
|
||||
int GameBoy::cyclesSinceLastRefresh()
|
||||
{
|
||||
int difference = cycles - lastRefresh;
|
||||
if (difference < 0)
|
||||
{
|
||||
// Handle the case when cycles has wrapped around (overflowed)
|
||||
difference += T_CLOCK_FREQ;
|
||||
}
|
||||
return difference;
|
||||
}
|
||||
|
||||
void GameBoy::checkPPUMode()
|
||||
{
|
||||
int oamFetchTime = 0;
|
||||
if ((*LY) < 144)
|
||||
{
|
||||
int currentDuration = cyclesSinceLastScanline();
|
||||
// Active Display Period (HBlank, OAM Search, and Pixel Transfer)
|
||||
if(currentDuration < MODE2_DURATION)
|
||||
setPPUMode(PPUMode::mode2);
|
||||
else if(currentDuration < MODE2_DURATION + MODE3_BASE_DURATION + oamFetchTime)
|
||||
setPPUMode(PPUMode::mode3);
|
||||
else
|
||||
setPPUMode(PPUMode::mode0);
|
||||
}
|
||||
// VBlank Period
|
||||
else
|
||||
setPPUMode(PPUMode::mode1);
|
||||
}
|
||||
|
||||
void GameBoy::setPPUMode(PPUMode mode)
|
||||
{
|
||||
switch(mode)
|
||||
{
|
||||
case PPUMode::mode0:
|
||||
(*STAT) &= ~0x03;
|
||||
break;
|
||||
case PPUMode::mode1:
|
||||
(*STAT) &= ~0x03;
|
||||
(*STAT) |= 0x01;
|
||||
//set vblank interrupt flag
|
||||
(*IF) |= 0x01;
|
||||
break;
|
||||
case PPUMode::mode2:
|
||||
(*STAT) &= ~0x03;
|
||||
(*STAT) |= 0x02;
|
||||
break;
|
||||
case PPUMode::mode3:
|
||||
(*STAT) &= ~0x03;
|
||||
(*STAT) |= 0x03;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
void GameBoy::drawLine()
|
||||
{
|
||||
uint8_t line = (*LY);
|
||||
|
||||
// Calculate the starting index of the current scanline in the framebuffer
|
||||
uint32_t lineStartIndex = line * RESOLUTION_X;
|
||||
|
||||
// Pointer to the current line's pixel data in the framebuffer
|
||||
uint32_t* currentLinePixels = framebuffer + lineStartIndex;
|
||||
|
||||
// For example, if you are setting the entire scanline to a color (e.g., white):
|
||||
for (int i = 0; i < RESOLUTION_X; i++)
|
||||
{
|
||||
// Assuming white color is represented as 0xFFFFFFFF (ARGB format)
|
||||
// if(currentLinePixels[i] == 0xFFFFFFFF)
|
||||
// currentLinePixels[i] = 0xFF000000;
|
||||
// else
|
||||
currentLinePixels[i] = 0xFFFFFFFF;
|
||||
}
|
||||
}
|
||||
|
||||
void GameBoy::SDL2setup()
|
||||
{
|
||||
SDL_Init(SDL_INIT_EVERYTHING);
|
||||
screen = SDL_CreateWindow("GBpp",
|
||||
SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
|
||||
RESOLUTION_X, RESOLUTION_Y,
|
||||
SDL_WINDOW_OPENGL);
|
||||
|
||||
// Create an SDL renderer to draw on the window
|
||||
renderer = SDL_CreateRenderer(screen, -1, SDL_RENDERER_ACCELERATED);
|
||||
|
||||
// Create an SDL texture to hold the framebuffer data
|
||||
texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888,
|
||||
SDL_TEXTUREACCESS_STREAMING, RESOLUTION_X, RESOLUTION_Y);
|
||||
}
|
||||
|
||||
void GameBoy::SDL2destroy()
|
||||
{
|
||||
SDL_DestroyTexture(texture);
|
||||
SDL_DestroyRenderer(renderer);
|
||||
SDL_DestroyWindow(screen);
|
||||
SDL_Quit();
|
||||
}
|
||||
|
||||
void GameBoy::SDL2present()
|
||||
{
|
||||
// Update the SDL texture with the framebuffer data
|
||||
SDL_UpdateTexture(texture, NULL, framebuffer, RESOLUTION_X * sizeof(uint32_t));
|
||||
|
||||
// Clear the renderer and render the texture
|
||||
SDL_RenderClear(renderer);
|
||||
SDL_RenderCopy(renderer, texture, NULL, NULL);
|
||||
|
||||
// Present the renderer on the screen
|
||||
SDL_RenderPresent(renderer);
|
||||
}
|
||||
Reference in New Issue
Block a user