/** * MIT License * * Copyright (c) 2018-2022 Mahyar Koshkouei * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to * deal in the Software without restriction, including without limitation the * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or * sell copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. * * Please note that at least three parts of source code within this project was * taken from the SameBoy project at https://github.com/LIJI32/SameBoy/ which at * the time of this writing is released under the MIT License. Occurrences of * this code is marked as being taken from SameBoy with a comment. * SameBoy, and code marked as being taken from SameBoy, * is Copyright (c) 2015-2019 Lior Halphon. */ #ifndef PEANUT_GB_H #define PEANUT_GB_H #if defined(__has_include) # if __has_include("version.all") # include "version.all" /* Version information */ # endif #else /* Stub __has_include for later. */ # define __has_include(x) 0 #endif #include /* Required for qsort and abort */ #include /* Required for int types */ #include /* Required for memset */ #include /* Required for tm struct */ /** * If PEANUT_GB_IS_LITTLE_ENDIAN is positive, then Peanut-GB will be configured * for a little endian platform. If 0, then big endian. */ #if !defined(PEANUT_GB_IS_LITTLE_ENDIAN) /* If endian is not defined, then attempt to detect it. */ # if defined(__BYTE_ORDER__) # if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ /* Building for a big endian platform. */ # define PEANUT_GB_IS_LITTLE_ENDIAN 0 # else # define PEANUT_GB_IS_LITTLE_ENDIAN 1 # endif /* __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ */ # elif defined(_WIN32) /* We assume that Windows is always little endian by default. */ # define PEANUT_GB_IS_LITTLE_ENDIAN 1 # elif !defined(PEANUT_GB_IS_LITTLE_ENDIAN) # error "Could not detect target platform endian. Please define PEANUT_GB_IS_LITTLE_ENDIAN" # endif #endif /* !defined(PEANUT_GB_IS_LITTLE_ENDIAN) */ #if PEANUT_GB_IS_LITTLE_ENDIAN == 0 # error "Peanut-GB only supports little endian targets" /* This is because the logic has been written with assumption of little * endian byte order. */ #endif /** Definitions for compile-time setting of features. **/ /** * Sound support must be provided by an external library. When audio_read() and * audio_write() functions are provided, define ENABLE_SOUND to a non-zero value * before including peanut_gb.h in order for these functions to be used. */ #ifndef ENABLE_SOUND # define ENABLE_SOUND 0 #endif /* Enable LCD drawing. On by default. May be turned off for testing purposes. */ #ifndef ENABLE_LCD # define ENABLE_LCD 1 #endif /* Adds more code to improve LCD rendering accuracy. */ #ifndef PEANUT_GB_HIGH_LCD_ACCURACY # define PEANUT_GB_HIGH_LCD_ACCURACY 1 #endif /* Play BIOS before playing cartridge. * This setting is currently not implemented. */ #ifndef PEANUT_GB_USE_BIOS # define PEANUT_GB_USE_BIOS 0 #endif /* Use intrinsic functions. This may produce smaller and faster code. */ #ifndef PEANUT_GB_USE_INTRINSICS # define PEANUT_GB_USE_INTRINSICS 1 #endif /* Function definition for abort(). */ #ifndef PEANUT_GB_ABORT # define PEANUT_GB_ABORT() abort() #endif /** Internal source code. **/ /* Interrupt masks */ #define VBLANK_INTR 0x01 #define LCDC_INTR 0x02 #define TIMER_INTR 0x04 #define SERIAL_INTR 0x08 #define CONTROL_INTR 0x10 #define ANY_INTR 0x1F /* Memory section sizes for DMG */ #define WRAM_SIZE 0x2000 #define VRAM_SIZE 0x2000 #define HRAM_IO_SIZE 0x0100 #define OAM_SIZE 0x00A0 /* Memory addresses */ #define ROM_0_ADDR 0x0000 #define ROM_N_ADDR 0x4000 #define VRAM_ADDR 0x8000 #define CART_RAM_ADDR 0xA000 #define WRAM_0_ADDR 0xC000 #define WRAM_1_ADDR 0xD000 #define ECHO_ADDR 0xE000 #define OAM_ADDR 0xFE00 #define UNUSED_ADDR 0xFEA0 #define IO_ADDR 0xFF00 #define HRAM_ADDR 0xFF80 #define INTR_EN_ADDR 0xFFFF /* Cart section sizes */ #define ROM_BANK_SIZE 0x4000 #define WRAM_BANK_SIZE 0x1000 #define CRAM_BANK_SIZE 0x2000 #define VRAM_BANK_SIZE 0x2000 /* DIV Register is incremented at rate of 16384Hz. * 4194304 / 16384 = 256 clock cycles for one increment. */ #define DIV_CYCLES 256 /* Serial clock locked to 8192Hz on DMG. * 4194304 / (8192 / 8) = 4096 clock cycles for sending 1 byte. */ #define SERIAL_CYCLES 4096 /* Calculating VSYNC. */ #define DMG_CLOCK_FREQ 4194304.0 #define SCREEN_REFRESH_CYCLES 70224.0 #define VERTICAL_SYNC (DMG_CLOCK_FREQ/SCREEN_REFRESH_CYCLES) /* SERIAL SC register masks. */ #define SERIAL_SC_TX_START 0x80 #define SERIAL_SC_CLOCK_SRC 0x01 /* STAT register masks */ #define STAT_LYC_INTR 0x40 #define STAT_MODE_2_INTR 0x20 #define STAT_MODE_1_INTR 0x10 #define STAT_MODE_0_INTR 0x08 #define STAT_LYC_COINC 0x04 #define STAT_MODE 0x03 #define STAT_USER_BITS 0xF8 /* LCDC control masks */ #define LCDC_ENABLE 0x80 #define LCDC_WINDOW_MAP 0x40 #define LCDC_WINDOW_ENABLE 0x20 #define LCDC_TILE_SELECT 0x10 #define LCDC_BG_MAP 0x08 #define LCDC_OBJ_SIZE 0x04 #define LCDC_OBJ_ENABLE 0x02 #define LCDC_BG_ENABLE 0x01 /* LCD characteristics */ #define LCD_LINE_CYCLES 456 #define LCD_MODE_0_CYCLES 0 #define LCD_MODE_2_CYCLES 204 #define LCD_MODE_3_CYCLES 284 #define LCD_VERT_LINES 154 #define LCD_WIDTH 160 #define LCD_HEIGHT 144 /* VRAM Locations */ #define VRAM_TILES_1 (0x8000 - VRAM_ADDR) #define VRAM_TILES_2 (0x8800 - VRAM_ADDR) #define VRAM_BMAP_1 (0x9800 - VRAM_ADDR) #define VRAM_BMAP_2 (0x9C00 - VRAM_ADDR) #define VRAM_TILES_3 (0x8000 - VRAM_ADDR + VRAM_BANK_SIZE) #define VRAM_TILES_4 (0x8800 - VRAM_ADDR + VRAM_BANK_SIZE) /* Interrupt jump addresses */ #define VBLANK_INTR_ADDR 0x0040 #define LCDC_INTR_ADDR 0x0048 #define TIMER_INTR_ADDR 0x0050 #define SERIAL_INTR_ADDR 0x0058 #define CONTROL_INTR_ADDR 0x0060 /* SPRITE controls */ #define NUM_SPRITES 0x28 #define MAX_SPRITES_LINE 0x0A #define OBJ_PRIORITY 0x80 #define OBJ_FLIP_Y 0x40 #define OBJ_FLIP_X 0x20 #define OBJ_PALETTE 0x10 #define ROM_HEADER_CHECKSUM_LOC 0x014D /* Local macros. */ #ifndef MIN # define MIN(a, b) ((a) < (b) ? (a) : (b)) #endif #define PEANUT_GB_ARRAYSIZE(array) (sizeof(array)/sizeof(array[0])) #if !defined(__has_builtin) /* Stub __has_builtin if it isn't available. */ # define __has_builtin(x) 0 #endif #if __has_builtin(__builtin_unreachable) # define PGB_UNREACHABLE() __builtin_unreachable() #else # define PGB_UNREACHABLE() PEANUT_GB_ABORT() #endif #if PEANUT_GB_USE_INTRINSICS /* If using MSVC, only enable intrinsics for x86 platforms*/ # if defined(_MSC_VER) && __has_include("intrin.h") && \ (defined(_M_IX86_FP) || defined(_M_AMD64) || defined(_M_X64)) /* Define instrinsic functions for MSVC. */ # include # define PGB_INTRIN_SBC(x,y,cin,res) _subborrow_u8(cin,x,y,&res) # define PGB_INTRIN_ADC(x,y,cin,res) _addcarry_u8(cin,x,y,&res) # endif /* MSVC */ /* Check for instrinsic functions in GCC and Clang. */ # if __has_builtin(__builtin_sub_overflow) # define PGB_INTRIN_SBC(x,y,cin,res) __builtin_sub_overflow(x,y+cin,&res) # define PGB_INTRIN_ADC(x,y,cin,res) __builtin_add_overflow(x,y+cin,&res) # endif #endif /* PEANUT_GB_USE_INTRINSICS */ #if defined(PGB_INTRIN_SBC) # define PGB_INSTR_SBC_R8(r,cin) \ { \ uint8_t temp; \ gb->cpu_reg.f_bits.c = PGB_INTRIN_SBC(gb->cpu_reg.a,r,cin,temp);\ gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a ^ r ^ temp) & 0x10) > 0; \ gb->cpu_reg.f_bits.n = 1; \ gb->cpu_reg.f_bits.z = (temp == 0x00); \ gb->cpu_reg.a = temp; \ } # define PGB_INSTR_CP_R8(r) \ { \ uint8_t temp; \ gb->cpu_reg.f_bits.c = PGB_INTRIN_SBC(gb->cpu_reg.a,r,0,temp); \ gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a ^ r ^ temp) & 0x10) > 0; \ gb->cpu_reg.f_bits.n = 1; \ gb->cpu_reg.f_bits.z = (temp == 0x00); \ } #else # define PGB_INSTR_SBC_R8(r,cin) \ { \ uint16_t temp = gb->cpu_reg.a - (r + cin); \ gb->cpu_reg.f_bits.c = (temp & 0xFF00) ? 1 : 0; \ gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a ^ r ^ temp) & 0x10) > 0; \ gb->cpu_reg.f_bits.n = 1; \ gb->cpu_reg.f_bits.z = ((temp & 0xFF) == 0x00); \ gb->cpu_reg.a = (temp & 0xFF); \ } # define PGB_INSTR_CP_R8(r) \ { \ uint16_t temp = gb->cpu_reg.a - r; \ gb->cpu_reg.f_bits.c = (temp & 0xFF00) ? 1 : 0; \ gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a ^ r ^ temp) & 0x10) > 0; \ gb->cpu_reg.f_bits.n = 1; \ gb->cpu_reg.f_bits.z = ((temp & 0xFF) == 0x00); \ } #endif /* PGB_INTRIN_SBC */ #if defined(PGB_INTRIN_ADC) # define PGB_INSTR_ADC_R8(r,cin) \ { \ uint8_t temp; \ gb->cpu_reg.f_bits.c = PGB_INTRIN_ADC(gb->cpu_reg.a,r,cin,temp);\ gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a ^ r ^ temp) & 0x10) > 0; \ gb->cpu_reg.f_bits.n = 0; \ gb->cpu_reg.f_bits.z = (temp == 0x00); \ gb->cpu_reg.a = temp; \ } #else # define PGB_INSTR_ADC_R8(r,cin) \ { \ uint16_t temp = gb->cpu_reg.a + r + cin; \ gb->cpu_reg.f_bits.c = (temp & 0xFF00) ? 1 : 0; \ gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a ^ r ^ temp) & 0x10) > 0; \ gb->cpu_reg.f_bits.n = 0; \ gb->cpu_reg.f_bits.z = ((temp & 0xFF) == 0x00); \ gb->cpu_reg.a = (temp & 0xFF); \ } #endif /* PGB_INTRIN_ADC */ #define PGB_INSTR_DEC_R8(r) \ r--; \ gb->cpu_reg.f_bits.h = ((r & 0x0F) == 0x0F); \ gb->cpu_reg.f_bits.n = 1; \ gb->cpu_reg.f_bits.z = (r == 0x00); #if PEANUT_GB_IS_LITTLE_ENDIAN # define PEANUT_GB_GET_LSB16(x) (x & 0xFF) # define PEANUT_GB_GET_MSB16(x) (x >> 8) # define PEANUT_GB_GET_MSN16(x) (x >> 12) # define PEANUT_GB_U8_TO_U16(h,l) ((l) | ((h) << 8)) #else # define PEANUT_GB_GET_LSB16(x) (x >> 8) # define PEANUT_GB_GET_MSB16(x) (x & 0xFF) # define PEANUT_GB_GET_MSN16(x) ((x & 0xF0) >> 4) # define PEANUT_GB_U8_TO_U16(h,l) ((h) | ((l) << 8)) #endif struct cpu_registers_s { /* Change register order if big endian. * Macro receives registers in little endian order. */ #if PEANUT_GB_IS_LITTLE_ENDIAN # define PEANUT_GB_LE_REG(x,y) x,y #else # define PEANUT_GB_LE_REG(x,y) y,x #endif /* Define specific bits of Flag register. */ struct { unsigned c : 1; /* Carry flag. */ unsigned h : 1; /* Half carry flag. */ unsigned n : 1; /* Add/sub flag. */ unsigned z : 1; /* Zero flag. */ } f_bits; uint8_t a; union { struct { uint8_t PEANUT_GB_LE_REG(c,b); } bytes; uint16_t reg; } bc; union { struct { uint8_t PEANUT_GB_LE_REG(e,d); } bytes; uint16_t reg; } de; union { struct { uint8_t PEANUT_GB_LE_REG(l,h); } bytes; uint16_t reg; } hl; /* Stack pointer */ union { struct { uint8_t PEANUT_GB_LE_REG(p, s); } bytes; uint16_t reg; } sp; /* Program counter */ union { struct { uint8_t PEANUT_GB_LE_REG(c, p); } bytes; uint16_t reg; } pc; #undef PEANUT_GB_LE_REG }; struct count_s { uint_fast16_t lcd_count; /* LCD Timing */ uint_fast16_t div_count; /* Divider Register Counter */ uint_fast16_t tima_count; /* Timer Counter */ uint_fast16_t serial_count; /* Serial Counter */ }; #define IO_JOYP 0x00 #define IO_SB 0x01 #define IO_SC 0x02 #define IO_DIV 0x04 #define IO_TIMA 0x05 #define IO_TMA 0x06 #define IO_TAC 0x07 #define IO_IF 0x0F #define IO_BOOT 0x50 #define IO_LCDC 0x40 #define IO_STAT 0x41 #define IO_SCY 0x42 #define IO_SCX 0x43 #define IO_LY 0x44 #define IO_LYC 0x45 #define IO_DMA 0x46 #define IO_BGP 0x47 #define IO_OBP0 0x48 #define IO_OBP1 0x49 #define IO_WY 0x4A #define IO_WX 0x4B #define IO_IE 0xFF #define IO_TAC_RATE_MASK 0x3 #define IO_TAC_ENABLE_MASK 0x4 /* LCD Mode defines. */ #define IO_STAT_MODE_HBLANK 0 #define IO_STAT_MODE_VBLANK 1 #define IO_STAT_MODE_SEARCH_OAM 2 #define IO_STAT_MODE_SEARCH_TRANSFER 3 #define IO_STAT_MODE_VBLANK_OR_TRANSFER_MASK 0x1 #if ENABLE_LCD /* Bit mask for the shade of pixel to display */ #define LCD_COLOUR 0x03 /** * Bit mask for whether a pixel is OBJ0, OBJ1, or BG. Each may have a different * palette when playing a DMG game on CGB. */ #define LCD_PALETTE_OBJ 0x10 #define LCD_PALETTE_BG 0x20 /** * Bit mask for the two bits listed above. * LCD_PALETTE_ALL == 0b00 --> OBJ0 * LCD_PALETTE_ALL == 0b01 --> OBJ1 * LCD_PALETTE_ALL == 0b10 --> BG * LCD_PALETTE_ALL == 0b11 --> NOT POSSIBLE */ #define LCD_PALETTE_ALL 0x30 #endif /** * Errors that may occur during emulation. */ enum gb_error_e { GB_UNKNOWN_ERROR = 0, GB_INVALID_OPCODE, GB_INVALID_READ, GB_INVALID_WRITE, GB_HALT_FOREVER, GB_INVALID_MAX }; /** * Errors that may occur during library initialisation. */ enum gb_init_error_e { GB_INIT_NO_ERROR = 0, GB_INIT_CARTRIDGE_UNSUPPORTED, GB_INIT_INVALID_CHECKSUM }; /** * Return codes for serial receive function, mainly for clarity. */ enum gb_serial_rx_ret_e { GB_SERIAL_RX_SUCCESS = 0, GB_SERIAL_RX_NO_CONNECTION = 1 }; /** * Emulator context. * * Only values within the `direct` struct may be modified directly by the * front-end implementation. Other variables must not be modified. */ struct gb_s { /** * Return byte from ROM at given address. * * \param gb_s emulator context * \param addr address * \return byte at address in ROM */ uint8_t (*gb_rom_read)(struct gb_s*, const uint_fast32_t addr); /** * Return byte from cart RAM at given address. * * \param gb_s emulator context * \param addr address * \return byte at address in RAM */ uint8_t (*gb_cart_ram_read)(struct gb_s*, const uint_fast32_t addr); /** * Write byte to cart RAM at given address. * * \param gb_s emulator context * \param addr address * \param val value to write to address in RAM */ void (*gb_cart_ram_write)(struct gb_s*, const uint_fast32_t addr, const uint8_t val); /** * Notify front-end of error. * * \param gb_s emulator context * \param gb_error_e error code * \param addr address of where error occured */ void (*gb_error)(struct gb_s*, const enum gb_error_e, const uint16_t addr); /* Transmit one byte and return the received byte. */ void (*gb_serial_tx)(struct gb_s*, const uint8_t tx); enum gb_serial_rx_ret_e (*gb_serial_rx)(struct gb_s*, uint8_t* rx); struct { unsigned gb_halt : 1; unsigned gb_ime : 1; #if PEANUT_GB_USE_BIOS unsigned gb_bios_enable : 1; #endif unsigned gb_frame : 1; /* New frame drawn. */ unsigned lcd_blank : 1; }; /* Cartridge information: * Memory Bank Controller (MBC) type. */ int8_t mbc; /* Whether the MBC has internal RAM. */ uint8_t cart_ram; /* Number of ROM banks in cartridge. */ uint16_t num_rom_banks_mask; /* Number of RAM banks in cartridge. */ uint8_t num_ram_banks; uint16_t selected_rom_bank; /* WRAM and VRAM bank selection not available. */ uint8_t cart_ram_bank; uint8_t enable_cart_ram; /* Cartridge ROM/RAM mode select. */ uint8_t cart_mode_select; union { struct { uint8_t sec; uint8_t min; uint8_t hour; uint8_t yday; uint8_t high; } rtc_bits; uint8_t cart_rtc[5]; }; struct cpu_registers_s cpu_reg; //struct gb_registers_s gb_reg; struct count_s counter; /* TODO: Allow implementation to allocate WRAM, VRAM and Frame Buffer. */ uint8_t wram[WRAM_SIZE]; uint8_t vram[VRAM_SIZE]; uint8_t oam[OAM_SIZE]; uint8_t hram_io[HRAM_IO_SIZE]; struct { /** * Draw line on screen. * * \param gb_s emulator context * \param pixels The 160 pixels to draw. * Bits 1-0 are the colour to draw. * Bits 5-4 are the palette, where: * OBJ0 = 0b00, * OBJ1 = 0b01, * BG = 0b10 * Other bits are undefined. * Bits 5-4 are only required by front-ends * which want to use a different colour for * different object palettes. This is what * the Game Boy Color (CGB) does to DMG * games. * \param line Line to draw pixels on. This is * guaranteed to be between 0-144 inclusive. */ void (*lcd_draw_line)(struct gb_s *gb, const uint8_t *pixels, const uint_fast8_t line); /* Palettes */ uint8_t bg_palette[4]; uint8_t sp_palette[8]; uint8_t window_clear; uint8_t WY; /* Only support 30fps frame skip. */ unsigned frame_skip_count : 1; unsigned interlace_count : 1; } display; /** * Variables that may be modified directly by the front-end. * This method seems to be easier and possibly less overhead than * calling a function to modify these variables each time. * * None of this is thread-safe. */ struct { /* Set to enable interlacing. Interlacing will start immediately * (at the next line drawing). */ unsigned interlace : 1; unsigned frame_skip : 1; union { struct { unsigned a : 1; unsigned b : 1; unsigned select : 1; unsigned start : 1; unsigned right : 1; unsigned left : 1; unsigned up : 1; unsigned down : 1; } joypad_bits; uint8_t joypad; }; /* Implementation defined data. Set to NULL if not required. */ void *priv; } direct; }; /** * Internal function used to read bytes. * addr is host platform endian. */ uint8_t __gb_read(struct gb_s *gb, const uint16_t addr) { switch(PEANUT_GB_GET_MSN16(addr)) { case 0x0: /* TODO: BIOS support. */ case 0x1: case 0x2: case 0x3: return gb->gb_rom_read(gb, addr); case 0x4: case 0x5: case 0x6: case 0x7: if(gb->mbc == 1 && gb->cart_mode_select) return gb->gb_rom_read(gb, addr + ((gb->selected_rom_bank & 0x1F) - 1) * ROM_BANK_SIZE); else return gb->gb_rom_read(gb, addr + (gb->selected_rom_bank - 1) * ROM_BANK_SIZE); case 0x8: case 0x9: return gb->vram[addr - VRAM_ADDR]; case 0xA: case 0xB: if(gb->cart_ram && gb->enable_cart_ram) { if(gb->mbc == 3 && gb->cart_ram_bank >= 0x08) return gb->cart_rtc[gb->cart_ram_bank - 0x08]; else if((gb->cart_mode_select || gb->mbc != 1) && gb->cart_ram_bank < gb->num_ram_banks) { return gb->gb_cart_ram_read(gb, addr - CART_RAM_ADDR + (gb->cart_ram_bank * CRAM_BANK_SIZE)); } else return gb->gb_cart_ram_read(gb, addr - CART_RAM_ADDR); } return 0xFF; case 0xC: return gb->wram[addr - WRAM_0_ADDR]; case 0xD: return gb->wram[addr - WRAM_1_ADDR + WRAM_BANK_SIZE]; case 0xE: return gb->wram[addr - ECHO_ADDR]; case 0xF: if(addr < OAM_ADDR) return gb->wram[addr - ECHO_ADDR]; if(addr < UNUSED_ADDR) return gb->oam[addr - OAM_ADDR]; /* Unusable memory area. Reading from this area returns 0xFF.*/ if(addr < IO_ADDR) return 0xFF; /* APU registers. */ if((addr >= 0xFF10) && (addr <= 0xFF3F)) { #if ENABLE_SOUND return audio_read(addr); #else static const uint8_t ortab[] = { 0x80, 0x3f, 0x00, 0xff, 0xbf, 0xff, 0x3f, 0x00, 0xff, 0xbf, 0x7f, 0xff, 0x9f, 0xff, 0xbf, 0xff, 0xff, 0x00, 0x00, 0xbf, 0x00, 0x00, 0x70, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; return gb->hram_io[addr - IO_ADDR] | ortab[addr - IO_ADDR]; #endif } /* HRAM */ if(addr >= IO_ADDR) return gb->hram_io[addr - IO_ADDR]; } /* Return address that caused read error. */ (gb->gb_error)(gb, GB_INVALID_READ, addr); PGB_UNREACHABLE(); } /** * Internal function used to write bytes. */ void __gb_write(struct gb_s *gb, const uint_fast16_t addr, const uint8_t val) { switch(PEANUT_GB_GET_MSN16(addr)) { case 0x0: case 0x1: if(gb->mbc == 2 && addr & 0x10) return; else if(gb->mbc > 0 && gb->cart_ram) gb->enable_cart_ram = ((val & 0x0F) == 0x0A); return; case 0x2: if(gb->mbc == 5) { gb->selected_rom_bank = (gb->selected_rom_bank & 0x100) | val; gb->selected_rom_bank = gb->selected_rom_bank & gb->num_rom_banks_mask; return; } /* Intentional fall through. */ case 0x3: if(gb->mbc == 1) { //selected_rom_bank = val & 0x7; gb->selected_rom_bank = (val & 0x1F) | (gb->selected_rom_bank & 0x60); if((gb->selected_rom_bank & 0x1F) == 0x00) gb->selected_rom_bank++; } else if(gb->mbc == 2 && addr & 0x10) { gb->selected_rom_bank = val & 0x0F; if(!gb->selected_rom_bank) gb->selected_rom_bank++; } else if(gb->mbc == 3) { gb->selected_rom_bank = val & 0x7F; if(!gb->selected_rom_bank) gb->selected_rom_bank++; } else if(gb->mbc == 5) gb->selected_rom_bank = (val & 0x01) << 8 | (gb->selected_rom_bank & 0xFF); gb->selected_rom_bank = gb->selected_rom_bank & gb->num_rom_banks_mask; return; case 0x4: case 0x5: if(gb->mbc == 1) { gb->cart_ram_bank = (val & 3); gb->selected_rom_bank = ((val & 3) << 5) | (gb->selected_rom_bank & 0x1F); gb->selected_rom_bank = gb->selected_rom_bank & gb->num_rom_banks_mask; } else if(gb->mbc == 3) gb->cart_ram_bank = val; else if(gb->mbc == 5) gb->cart_ram_bank = (val & 0x0F); return; case 0x6: case 0x7: gb->cart_mode_select = (val & 1); return; case 0x8: case 0x9: gb->vram[addr - VRAM_ADDR] = val; return; case 0xA: case 0xB: if(gb->cart_ram && gb->enable_cart_ram) { if(gb->mbc == 3 && gb->cart_ram_bank >= 0x08) gb->cart_rtc[gb->cart_ram_bank - 0x08] = val; else if(gb->cart_mode_select && gb->cart_ram_bank < gb->num_ram_banks) { gb->gb_cart_ram_write(gb, addr - CART_RAM_ADDR + (gb->cart_ram_bank * CRAM_BANK_SIZE), val); } else if(gb->num_ram_banks) gb->gb_cart_ram_write(gb, addr - CART_RAM_ADDR, val); } return; case 0xC: gb->wram[addr - WRAM_0_ADDR] = val; return; case 0xD: gb->wram[addr - WRAM_1_ADDR + WRAM_BANK_SIZE] = val; return; case 0xE: gb->wram[addr - ECHO_ADDR] = val; return; case 0xF: if(addr < OAM_ADDR) { gb->wram[addr - ECHO_ADDR] = val; return; } if(addr < UNUSED_ADDR) { gb->oam[addr - OAM_ADDR] = val; return; } /* Unusable memory area. */ if(addr < IO_ADDR) return; if(HRAM_ADDR <= addr && addr < INTR_EN_ADDR) { gb->hram_io[addr - IO_ADDR] = val; return; } if((addr >= 0xFF10) && (addr <= 0xFF3F)) { #if ENABLE_SOUND audio_write(addr, val); #else gb->hram_io[addr - IO_ADDR] = val; #endif return; } /* IO and Interrupts. */ switch(PEANUT_GB_GET_LSB16(addr)) { /* Joypad */ case 0x00: /* Only bits 5 and 4 are R/W. * The lower bits are overwritten later, and the two most * significant bits are unused. */ gb->hram_io[IO_JOYP] = val; /* Direction keys selected */ if((gb->hram_io[IO_JOYP] & 0b010000) == 0) gb->hram_io[IO_JOYP] |= (gb->direct.joypad >> 4); /* Button keys selected */ else gb->hram_io[IO_JOYP] |= (gb->direct.joypad & 0x0F); return; /* Serial */ case 0x01: gb->hram_io[IO_SB] = val; return; case 0x02: gb->hram_io[IO_SC] = val; return; /* Timer Registers */ case 0x04: gb->hram_io[IO_DIV] = 0x00; return; case 0x05: gb->hram_io[IO_TIMA] = val; return; case 0x06: gb->hram_io[IO_TMA] = val; return; case 0x07: gb->hram_io[IO_TAC] = val; return; /* Interrupt Flag Register */ case 0x0F: gb->hram_io[IO_IF] = (val | 0b11100000); return; /* LCD Registers */ case 0x40: if(((gb->hram_io[IO_LCDC] & LCDC_ENABLE) == 0) && (val & LCDC_ENABLE)) { gb->counter.lcd_count = 0; gb->lcd_blank = 1; } gb->hram_io[IO_LCDC] = val; /* LY fixed to 0 when LCD turned off. */ if((gb->hram_io[IO_LCDC] & LCDC_ENABLE) == 0) { /* Do not turn off LCD outside of VBLANK. This may * happen due to poor timing in this emulator. */ if((gb->hram_io[IO_STAT] & STAT_MODE) != IO_STAT_MODE_VBLANK) { gb->hram_io[IO_LCDC] |= LCDC_ENABLE; return; } gb->hram_io[IO_STAT] = (gb->hram_io[IO_STAT] & ~0x03) | 1; gb->hram_io[IO_LY] = 0; gb->counter.lcd_count = 0; } return; case 0x41: gb->hram_io[IO_STAT] = (val & STAT_USER_BITS) | (gb->hram_io[IO_STAT] & STAT_MODE); return; case 0x42: gb->hram_io[IO_SCY] = val; return; case 0x43: gb->hram_io[IO_SCX] = val; return; /* LY (0xFF44) is read only. */ case 0x45: gb->hram_io[IO_LYC] = val; return; /* DMA Register */ case 0x46: { uint16_t dma_addr = (uint_fast16_t)val << 8; gb->hram_io[IO_DMA] = val; for(uint16_t i = 0; i < OAM_SIZE; i++) { gb->oam[i] = __gb_read(gb, dma_addr + i); } return; } /* DMG Palette Registers */ case 0x47: gb->hram_io[IO_BGP] = val; gb->display.bg_palette[0] = (gb->hram_io[IO_BGP] & 0x03); gb->display.bg_palette[1] = (gb->hram_io[IO_BGP] >> 2) & 0x03; gb->display.bg_palette[2] = (gb->hram_io[IO_BGP] >> 4) & 0x03; gb->display.bg_palette[3] = (gb->hram_io[IO_BGP] >> 6) & 0x03; return; case 0x48: gb->hram_io[IO_OBP0] = val; gb->display.sp_palette[0] = (gb->hram_io[IO_OBP0] & 0x03); gb->display.sp_palette[1] = (gb->hram_io[IO_OBP0] >> 2) & 0x03; gb->display.sp_palette[2] = (gb->hram_io[IO_OBP0] >> 4) & 0x03; gb->display.sp_palette[3] = (gb->hram_io[IO_OBP0] >> 6) & 0x03; return; case 0x49: gb->hram_io[IO_OBP1] = val; gb->display.sp_palette[4] = (gb->hram_io[IO_OBP1] & 0x03); gb->display.sp_palette[5] = (gb->hram_io[IO_OBP1] >> 2) & 0x03; gb->display.sp_palette[6] = (gb->hram_io[IO_OBP1] >> 4) & 0x03; gb->display.sp_palette[7] = (gb->hram_io[IO_OBP1] >> 6) & 0x03; return; /* Window Position Registers */ case 0x4A: gb->hram_io[IO_WY] = val; return; case 0x4B: gb->hram_io[IO_WX] = val; return; /* Turn off boot ROM */ case 0x50: #if PEANUT_GB_USE_BIOS gb->gb_bios_enable = 0; #endif return; /* Interrupt Enable Register */ case 0xFF: gb->hram_io[IO_IE] = val; return; } } /* Return address that caused write error. */ (gb->gb_error)(gb, GB_INVALID_WRITE, addr); PGB_UNREACHABLE(); } uint8_t __gb_execute_cb(struct gb_s *gb) { uint8_t inst_cycles; uint8_t cbop = __gb_read(gb, gb->cpu_reg.pc.reg++); uint8_t r = (cbop & 0x7); uint8_t b = (cbop >> 3) & 0x7; uint8_t d = (cbop >> 3) & 0x1; uint8_t val; uint8_t writeback = 1; inst_cycles = 8; /* Add an additional 8 cycles to these sets of instructions. */ switch(cbop & 0xC7) { case 0x06: case 0x86: case 0xC6: inst_cycles += 8; break; case 0x46: inst_cycles += 4; break; } switch(r) { case 0: val = gb->cpu_reg.bc.bytes.b; break; case 1: val = gb->cpu_reg.bc.bytes.c; break; case 2: val = gb->cpu_reg.de.bytes.d; break; case 3: val = gb->cpu_reg.de.bytes.e; break; case 4: val = gb->cpu_reg.hl.bytes.h; break; case 5: val = gb->cpu_reg.hl.bytes.l; break; case 6: val = __gb_read(gb, gb->cpu_reg.hl.reg); break; /* Only values 0-7 are possible here, so we make the final case * default to satisfy -Wmaybe-uninitialized warning. */ default: val = gb->cpu_reg.a; break; } /* TODO: Find out WTF this is doing. */ switch(cbop >> 6) { case 0x0: cbop = (cbop >> 4) & 0x3; switch(cbop) { case 0x0: /* RdC R */ case 0x1: /* Rd R */ if(d) /* RRC R / RR R */ { uint8_t temp = val; val = (val >> 1); val |= cbop ? (gb->cpu_reg.f_bits.c << 7) : (temp << 7); gb->cpu_reg.f_bits.z = (val == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = (temp & 0x01); } else /* RLC R / RL R */ { uint8_t temp = val; val = (val << 1); val |= cbop ? gb->cpu_reg.f_bits.c : (temp >> 7); gb->cpu_reg.f_bits.z = (val == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = (temp >> 7); } break; case 0x2: if(d) /* SRA R */ { gb->cpu_reg.f_bits.c = val & 0x01; val = (val >> 1) | (val & 0x80); gb->cpu_reg.f_bits.z = (val == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; } else /* SLA R */ { gb->cpu_reg.f_bits.c = (val >> 7); val = val << 1; gb->cpu_reg.f_bits.z = (val == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; } break; case 0x3: if(d) /* SRL R */ { gb->cpu_reg.f_bits.c = val & 0x01; val = val >> 1; gb->cpu_reg.f_bits.z = (val == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; } else /* SWAP R */ { uint8_t temp = (val >> 4) & 0x0F; temp |= (val << 4) & 0xF0; val = temp; gb->cpu_reg.f_bits.z = (val == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; } break; } break; case 0x1: /* BIT B, R */ gb->cpu_reg.f_bits.z = !((val >> b) & 0x1); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; writeback = 0; break; case 0x2: /* RES B, R */ val &= (0xFE << b) | (0xFF >> (8 - b)); break; case 0x3: /* SET B, R */ val |= (0x1 << b); break; } if(writeback) { switch(r) { case 0: gb->cpu_reg.bc.bytes.b = val; break; case 1: gb->cpu_reg.bc.bytes.c = val; break; case 2: gb->cpu_reg.de.bytes.d = val; break; case 3: gb->cpu_reg.de.bytes.e = val; break; case 4: gb->cpu_reg.hl.bytes.h = val; break; case 5: gb->cpu_reg.hl.bytes.l = val; break; case 6: __gb_write(gb, gb->cpu_reg.hl.reg, val); break; case 7: gb->cpu_reg.a = val; break; } } return inst_cycles; } #if ENABLE_LCD struct sprite_data { uint8_t sprite_number; uint8_t x; }; #if PEANUT_GB_HIGH_LCD_ACCURACY static int compare_sprites(const void *in1, const void *in2) { const struct sprite_data *sd1, *sd2; sd1 = (struct sprite_data *)in1; sd2 = (struct sprite_data *)in2; int x_res = (int)sd1->x - (int)sd2->x; if(x_res != 0) return x_res; return (int)sd1->sprite_number - (int)sd2->sprite_number; } #endif void __gb_draw_line(struct gb_s *gb) { uint8_t pixels[160] = {0}; /* If LCD not initialised by front-end, don't render anything. */ if(gb->display.lcd_draw_line == NULL) return; if(gb->direct.frame_skip && !gb->display.frame_skip_count) return; /* If interlaced mode is activated, check if we need to draw the current * line. */ if(gb->direct.interlace) { if((gb->display.interlace_count == 0 && (gb->hram_io[IO_LY] & 1) == 0) || (gb->display.interlace_count == 1 && (gb->hram_io[IO_LY] & 1) == 1)) { /* Compensate for missing window draw if required. */ if(gb->hram_io[IO_LCDC] & LCDC_WINDOW_ENABLE && gb->hram_io[IO_LY] >= gb->display.WY && gb->hram_io[IO_WX] <= 166) gb->display.window_clear++; return; } } /* If background is enabled, draw it. */ if(gb->hram_io[IO_LCDC] & LCDC_BG_ENABLE) { /* Calculate current background line to draw. Constant because * this function draws only this one line each time it is * called. */ const uint8_t bg_y = gb->hram_io[IO_LY] + gb->hram_io[IO_SCY]; /* Get selected background map address for first tile * corresponding to current line. * 0x20 (32) is the width of a background tile, and the bit * shift is to calculate the address. */ const uint16_t bg_map = ((gb->hram_io[IO_LCDC] & LCDC_BG_MAP) ? VRAM_BMAP_2 : VRAM_BMAP_1) + (bg_y >> 3) * 0x20; /* The displays (what the player sees) X coordinate, drawn right * to left. */ uint8_t disp_x = LCD_WIDTH - 1; /* The X coordinate to begin drawing the background at. */ uint8_t bg_x = disp_x + gb->hram_io[IO_SCX]; /* Get tile index for current background tile. */ uint8_t idx = gb->vram[bg_map + (bg_x >> 3)]; /* Y coordinate of tile pixel to draw. */ const uint8_t py = (bg_y & 0x07); /* X coordinate of tile pixel to draw. */ uint8_t px = 7 - (bg_x & 0x07); uint16_t tile; /* Select addressing mode. */ if(gb->hram_io[IO_LCDC] & LCDC_TILE_SELECT) tile = VRAM_TILES_1 + idx * 0x10; else tile = VRAM_TILES_2 + ((idx + 0x80) % 0x100) * 0x10; tile += 2 * py; /* fetch first tile */ uint8_t t1 = gb->vram[tile] >> px; uint8_t t2 = gb->vram[tile + 1] >> px; for(; disp_x != 0xFF; disp_x--) { if(px == 8) { /* fetch next tile */ px = 0; bg_x = disp_x + gb->hram_io[IO_SCX]; idx = gb->vram[bg_map + (bg_x >> 3)]; if(gb->hram_io[IO_LCDC] & LCDC_TILE_SELECT) tile = VRAM_TILES_1 + idx * 0x10; else tile = VRAM_TILES_2 + ((idx + 0x80) % 0x100) * 0x10; tile += 2 * py; t1 = gb->vram[tile]; t2 = gb->vram[tile + 1]; } /* copy background */ uint8_t c = (t1 & 0x1) | ((t2 & 0x1) << 1); pixels[disp_x] = gb->display.bg_palette[c]; pixels[disp_x] |= LCD_PALETTE_BG; t1 = t1 >> 1; t2 = t2 >> 1; px++; } } /* draw window */ if(gb->hram_io[IO_LCDC] & LCDC_WINDOW_ENABLE && gb->hram_io[IO_LY] >= gb->display.WY && gb->hram_io[IO_WX] <= 166) { /* Calculate Window Map Address. */ uint16_t win_line = (gb->hram_io[IO_LCDC] & LCDC_WINDOW_MAP) ? VRAM_BMAP_2 : VRAM_BMAP_1; win_line += (gb->display.window_clear >> 3) * 0x20; uint8_t disp_x = LCD_WIDTH - 1; uint8_t win_x = disp_x - gb->hram_io[IO_WX] + 7; // look up tile uint8_t py = gb->display.window_clear & 0x07; uint8_t px = 7 - (win_x & 0x07); uint8_t idx = gb->vram[win_line + (win_x >> 3)]; uint16_t tile; if(gb->hram_io[IO_LCDC] & LCDC_TILE_SELECT) tile = VRAM_TILES_1 + idx * 0x10; else tile = VRAM_TILES_2 + ((idx + 0x80) % 0x100) * 0x10; tile += 2 * py; // fetch first tile uint8_t t1 = gb->vram[tile] >> px; uint8_t t2 = gb->vram[tile + 1] >> px; // loop & copy window uint8_t end = (gb->hram_io[IO_WX] < 7 ? 0 : gb->hram_io[IO_WX] - 7) - 1; for(; disp_x != end; disp_x--) { if(px == 8) { // fetch next tile px = 0; win_x = disp_x - gb->hram_io[IO_WX] + 7; idx = gb->vram[win_line + (win_x >> 3)]; if(gb->hram_io[IO_LCDC] & LCDC_TILE_SELECT) tile = VRAM_TILES_1 + idx * 0x10; else tile = VRAM_TILES_2 + ((idx + 0x80) % 0x100) * 0x10; tile += 2 * py; t1 = gb->vram[tile]; t2 = gb->vram[tile + 1]; } // copy window uint8_t c = (t1 & 0x1) | ((t2 & 0x1) << 1); pixels[disp_x] = gb->display.bg_palette[c]; pixels[disp_x] |= LCD_PALETTE_BG; t1 = t1 >> 1; t2 = t2 >> 1; px++; } gb->display.window_clear++; // advance window line } // draw sprites if(gb->hram_io[IO_LCDC] & LCDC_OBJ_ENABLE) { #if PEANUT_GB_HIGH_LCD_ACCURACY uint8_t number_of_sprites = 0; struct sprite_data sprites_to_render[NUM_SPRITES]; /* Record number of sprites on the line being rendered, limited * to the maximum number sprites that the Game Boy is able to * render on each line (10 sprites). */ for(uint8_t sprite_number = 0; sprite_number < PEANUT_GB_ARRAYSIZE(sprites_to_render); sprite_number++) { /* Sprite Y position. */ uint8_t OY = gb->oam[4 * sprite_number + 0]; /* Sprite X position. */ uint8_t OX = gb->oam[4 * sprite_number + 1]; /* If sprite isn't on this line, continue. */ if (gb->hram_io[IO_LY] + (gb->hram_io[IO_LCDC] & LCDC_OBJ_SIZE ? 0 : 8) >= OY || gb->hram_io[IO_LY] + 16 < OY) continue; sprites_to_render[number_of_sprites].sprite_number = sprite_number; sprites_to_render[number_of_sprites].x = OX; number_of_sprites++; } /* If maximum number of sprites reached, prioritise X * coordinate and object location in OAM. */ qsort(&sprites_to_render[0], number_of_sprites, sizeof(sprites_to_render[0]), compare_sprites); if(number_of_sprites > MAX_SPRITES_LINE) number_of_sprites = MAX_SPRITES_LINE; #endif /* Render each sprite, from low priority to high priority. */ #if PEANUT_GB_HIGH_LCD_ACCURACY /* Render the top ten prioritised sprites on this scanline. */ for(uint8_t sprite_number = number_of_sprites - 1; sprite_number != 0xFF; sprite_number--) { uint8_t s = sprites_to_render[sprite_number].sprite_number; #else for (uint8_t sprite_number = NUM_SPRITES - 1; sprite_number != 0xFF; sprite_number--) { uint8_t s = sprite_number; #endif /* Sprite Y position. */ uint8_t OY = gb->oam[4 * s + 0]; /* Sprite X position. */ uint8_t OX = gb->oam[4 * s + 1]; /* Sprite Tile/Pattern Number. */ uint8_t OT = gb->oam[4 * s + 2] & (gb->hram_io[IO_LCDC] & LCDC_OBJ_SIZE ? 0xFE : 0xFF); /* Additional attributes. */ uint8_t OF = gb->oam[4 * s + 3]; #if !PEANUT_GB_HIGH_LCD_ACCURACY /* If sprite isn't on this line, continue. */ if(gb->hram_io[IO_LY] + (gb->hram_io[IO_LCDC] & LCDC_OBJ_SIZE ? 0 : 8) >= OY || gb->hram_io[IO_LY] + 16 < OY) continue; #endif /* Continue if sprite not visible. */ if(OX == 0 || OX >= 168) continue; // y flip uint8_t py = gb->hram_io[IO_LY] - OY + 16; if(OF & OBJ_FLIP_Y) py = (gb->hram_io[IO_LCDC] & LCDC_OBJ_SIZE ? 15 : 7) - py; // fetch the tile uint8_t t1 = gb->vram[VRAM_TILES_1 + OT * 0x10 + 2 * py]; uint8_t t2 = gb->vram[VRAM_TILES_1 + OT * 0x10 + 2 * py + 1]; // handle x flip uint8_t dir, start, end, shift; if(OF & OBJ_FLIP_X) { dir = 1; start = (OX < 8 ? 0 : OX - 8); end = MIN(OX, LCD_WIDTH); shift = 8 - OX + start; } else { dir = -1; start = MIN(OX, LCD_WIDTH) - 1; end = (OX < 8 ? 0 : OX - 8) - 1; shift = OX - (start + 1); } // copy tile t1 >>= shift; t2 >>= shift; for(uint8_t disp_x = start; disp_x != end; disp_x += dir) { uint8_t c = (t1 & 0x1) | ((t2 & 0x1) << 1); // check transparency / sprite overlap / background overlap #if 0 if(c // && OX <= fx[disp_x] && !((OF & OBJ_PRIORITY) && ((pixels[disp_x] & 0x3) && fx[disp_x] == 0xFE))) #else if(c && !(OF & OBJ_PRIORITY && pixels[disp_x] & 0x3)) #endif { /* Set pixel colour. */ pixels[disp_x] = (OF & OBJ_PALETTE) ? gb->display.sp_palette[c + 4] : gb->display.sp_palette[c]; /* Set pixel palette (OBJ0 or OBJ1). */ pixels[disp_x] |= (OF & OBJ_PALETTE); /* Deselect BG palette. */ pixels[disp_x] &= ~LCD_PALETTE_BG; } t1 = t1 >> 1; t2 = t2 >> 1; } } } gb->display.lcd_draw_line(gb, pixels, gb->hram_io[IO_LY]); } #endif /** * Internal function used to step the CPU. */ void __gb_step_cpu(struct gb_s *gb) { uint8_t opcode; uint_fast16_t inst_cycles; static const uint8_t op_cycles[0x100] = { /* *INDENT-OFF* */ /*0 1 2 3 4 5 6 7 8 9 A B C D E F */ 4,12, 8, 8, 4, 4, 8, 4,20, 8, 8, 8, 4, 4, 8, 4, /* 0x00 */ 4,12, 8, 8, 4, 4, 8, 4,12, 8, 8, 8, 4, 4, 8, 4, /* 0x10 */ 8,12, 8, 8, 4, 4, 8, 4, 8, 8, 8, 8, 4, 4, 8, 4, /* 0x20 */ 8,12, 8, 8,12,12,12, 4, 8, 8, 8, 8, 4, 4, 8, 4, /* 0x30 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0x40 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0x50 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0x60 */ 8, 8, 8, 8, 8, 8, 4, 8, 4, 4, 4, 4, 4, 4, 8, 4, /* 0x70 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0x80 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0x90 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0xA0 */ 4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4, /* 0xB0 */ 8,12,12,16,12,16, 8,16, 8,16,12, 8,12,24, 8,16, /* 0xC0 */ 8,12,12, 0,12,16, 8,16, 8,16,12, 0,12, 0, 8,16, /* 0xD0 */ 12,12,8, 0, 0,16, 8,16,16, 4,16, 0, 0, 0, 8,16, /* 0xE0 */ 12,12,8, 4, 0,16, 8,16,12, 8,16, 4, 0, 0, 8,16 /* 0xF0 */ /* *INDENT-ON* */ }; static const uint_fast16_t TAC_CYCLES[4] = {1024, 16, 64, 256}; /* Handle interrupts */ /* If gb_halt is positive, then an interrupt must have occured by the * time we reach here, becuase on HALT, we jump to the next interrupt * immediately. */ if(gb->gb_halt || (gb->gb_ime && gb->hram_io[IO_IF] & gb->hram_io[IO_IE] & ANY_INTR)) { gb->gb_halt = 0; if(gb->gb_ime) { /* Disable interrupts */ gb->gb_ime = 0; /* Push Program Counter */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); /* Call interrupt handler if required. */ if(gb->hram_io[IO_IF] & gb->hram_io[IO_IE] & VBLANK_INTR) { gb->cpu_reg.pc.reg = VBLANK_INTR_ADDR; gb->hram_io[IO_IF] ^= VBLANK_INTR; } else if(gb->hram_io[IO_IF] & gb->hram_io[IO_IE] & LCDC_INTR) { gb->cpu_reg.pc.reg = LCDC_INTR_ADDR; gb->hram_io[IO_IF] ^= LCDC_INTR; } else if(gb->hram_io[IO_IF] & gb->hram_io[IO_IE] & TIMER_INTR) { gb->cpu_reg.pc.reg = TIMER_INTR_ADDR; gb->hram_io[IO_IF] ^= TIMER_INTR; } else if(gb->hram_io[IO_IF] & gb->hram_io[IO_IE] & SERIAL_INTR) { gb->cpu_reg.pc.reg = SERIAL_INTR_ADDR; gb->hram_io[IO_IF] ^= SERIAL_INTR; } else if(gb->hram_io[IO_IF] & gb->hram_io[IO_IE] & CONTROL_INTR) { gb->cpu_reg.pc.reg = CONTROL_INTR_ADDR; gb->hram_io[IO_IF] ^= CONTROL_INTR; } } } /* Obtain opcode */ opcode = __gb_read(gb, gb->cpu_reg.pc.reg++); inst_cycles = op_cycles[opcode]; /* Execute opcode */ switch(opcode) { case 0x00: /* NOP */ break; case 0x01: /* LD BC, imm */ gb->cpu_reg.bc.bytes.c = __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.bc.bytes.b = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x02: /* LD (BC), A */ __gb_write(gb, gb->cpu_reg.bc.reg, gb->cpu_reg.a); break; case 0x03: /* INC BC */ gb->cpu_reg.bc.reg++; break; case 0x04: /* INC B */ gb->cpu_reg.bc.bytes.b++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.bc.bytes.b == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.bc.bytes.b & 0x0F) == 0x00); break; case 0x05: /* DEC B */ PGB_INSTR_DEC_R8(gb->cpu_reg.bc.bytes.b); break; case 0x06: /* LD B, imm */ gb->cpu_reg.bc.bytes.b = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x07: /* RLCA */ gb->cpu_reg.a = (gb->cpu_reg.a << 1) | (gb->cpu_reg.a >> 7); gb->cpu_reg.f_bits.z = 0; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = (gb->cpu_reg.a & 0x01); break; case 0x08: /* LD (imm), SP */ { uint8_t h, l; uint16_t temp; l = __gb_read(gb, gb->cpu_reg.pc.reg++); h = __gb_read(gb, gb->cpu_reg.pc.reg++); temp = PEANUT_GB_U8_TO_U16(h,l); __gb_write(gb, temp++, gb->cpu_reg.sp.bytes.p); __gb_write(gb, temp, gb->cpu_reg.sp.bytes.s); break; } case 0x09: /* ADD HL, BC */ { uint_fast32_t temp = gb->cpu_reg.hl.reg + gb->cpu_reg.bc.reg; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = (temp ^ gb->cpu_reg.hl.reg ^ gb->cpu_reg.bc.reg) & 0x1000 ? 1 : 0; gb->cpu_reg.f_bits.c = (temp & 0xFFFF0000) ? 1 : 0; gb->cpu_reg.hl.reg = (temp & 0x0000FFFF); break; } case 0x0A: /* LD A, (BC) */ gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.bc.reg); break; case 0x0B: /* DEC BC */ gb->cpu_reg.bc.reg--; break; case 0x0C: /* INC C */ gb->cpu_reg.bc.bytes.c++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.bc.bytes.c == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.bc.bytes.c & 0x0F) == 0x00); break; case 0x0D: /* DEC C */ PGB_INSTR_DEC_R8(gb->cpu_reg.bc.bytes.c); break; case 0x0E: /* LD C, imm */ gb->cpu_reg.bc.bytes.c = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x0F: /* RRCA */ gb->cpu_reg.f_bits.c = gb->cpu_reg.a & 0x01; gb->cpu_reg.a = (gb->cpu_reg.a >> 1) | (gb->cpu_reg.a << 7); gb->cpu_reg.f_bits.z = 0; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; break; case 0x10: /* STOP */ //gb->gb_halt = 1; break; case 0x11: /* LD DE, imm */ gb->cpu_reg.de.bytes.e = __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.de.bytes.d = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x12: /* LD (DE), A */ __gb_write(gb, gb->cpu_reg.de.reg, gb->cpu_reg.a); break; case 0x13: /* INC DE */ gb->cpu_reg.de.reg++; break; case 0x14: /* INC D */ gb->cpu_reg.de.bytes.d++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.de.bytes.d == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.de.bytes.d & 0x0F) == 0x00); break; case 0x15: /* DEC D */ PGB_INSTR_DEC_R8(gb->cpu_reg.de.bytes.d); break; case 0x16: /* LD D, imm */ gb->cpu_reg.de.bytes.d = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x17: /* RLA */ { uint8_t temp = gb->cpu_reg.a; gb->cpu_reg.a = (gb->cpu_reg.a << 1) | gb->cpu_reg.f_bits.c; gb->cpu_reg.f_bits.z = 0; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = (temp >> 7) & 0x01; break; } case 0x18: /* JR imm */ { int8_t temp = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.pc.reg += temp; break; } case 0x19: /* ADD HL, DE */ { uint_fast32_t temp = gb->cpu_reg.hl.reg + gb->cpu_reg.de.reg; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = (temp ^ gb->cpu_reg.hl.reg ^ gb->cpu_reg.de.reg) & 0x1000 ? 1 : 0; gb->cpu_reg.f_bits.c = (temp & 0xFFFF0000) ? 1 : 0; gb->cpu_reg.hl.reg = (temp & 0x0000FFFF); break; } case 0x1A: /* LD A, (DE) */ gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.de.reg); break; case 0x1B: /* DEC DE */ gb->cpu_reg.de.reg--; break; case 0x1C: /* INC E */ gb->cpu_reg.de.bytes.e++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.de.bytes.e == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.de.bytes.e & 0x0F) == 0x00); break; case 0x1D: /* DEC E */ PGB_INSTR_DEC_R8(gb->cpu_reg.de.bytes.e); break; case 0x1E: /* LD E, imm */ gb->cpu_reg.de.bytes.e = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x1F: /* RRA */ { uint8_t temp = gb->cpu_reg.a; gb->cpu_reg.a = gb->cpu_reg.a >> 1 | (gb->cpu_reg.f_bits.c << 7); gb->cpu_reg.f_bits.z = 0; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = temp & 0x1; break; } case 0x20: /* JR NZ, imm */ if(!gb->cpu_reg.f_bits.z) { int8_t temp = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.pc.reg += temp; inst_cycles += 4; } else gb->cpu_reg.pc.reg++; break; case 0x21: /* LD HL, imm */ gb->cpu_reg.hl.bytes.l = __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.hl.bytes.h = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x22: /* LDI (HL), A */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.a); gb->cpu_reg.hl.reg++; break; case 0x23: /* INC HL */ gb->cpu_reg.hl.reg++; break; case 0x24: /* INC H */ gb->cpu_reg.hl.bytes.h++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.hl.bytes.h == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.hl.bytes.h & 0x0F) == 0x00); break; case 0x25: /* DEC H */ PGB_INSTR_DEC_R8(gb->cpu_reg.hl.bytes.h); break; case 0x26: /* LD H, imm */ gb->cpu_reg.hl.bytes.h = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x27: /* DAA */ { /* The following is from SameBoy. MIT License. */ int16_t a = gb->cpu_reg.a; if(gb->cpu_reg.f_bits.n) { if(gb->cpu_reg.f_bits.h) a = (a - 0x06) & 0xFF; if(gb->cpu_reg.f_bits.c) a -= 0x60; } else { if(gb->cpu_reg.f_bits.h || (a & 0x0F) > 9) a += 0x06; if(gb->cpu_reg.f_bits.c || a > 0x9F) a += 0x60; } if((a & 0x100) == 0x100) gb->cpu_reg.f_bits.c = 1; gb->cpu_reg.a = a; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0); gb->cpu_reg.f_bits.h = 0; break; } case 0x28: /* JP Z, imm */ if(gb->cpu_reg.f_bits.z) { int8_t temp = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.pc.reg += temp; inst_cycles += 4; } else gb->cpu_reg.pc.reg++; break; case 0x29: /* ADD HL, HL */ { gb->cpu_reg.f_bits.c = (gb->cpu_reg.hl.reg & 0x8000) > 0; gb->cpu_reg.hl.reg <<= 1; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = (gb->cpu_reg.hl.reg & 0x1000) > 0; break; } case 0x2A: /* LD A, (HL+) */ gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.hl.reg++); break; case 0x2B: /* DEC HL */ gb->cpu_reg.hl.reg--; break; case 0x2C: /* INC L */ gb->cpu_reg.hl.bytes.l++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.hl.bytes.l == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.hl.bytes.l & 0x0F) == 0x00); break; case 0x2D: /* DEC L */ PGB_INSTR_DEC_R8(gb->cpu_reg.hl.bytes.l); break; case 0x2E: /* LD L, imm */ gb->cpu_reg.hl.bytes.l = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x2F: /* CPL */ gb->cpu_reg.a = ~gb->cpu_reg.a; gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = 1; break; case 0x30: /* JP NC, imm */ if(!gb->cpu_reg.f_bits.c) { int8_t temp = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.pc.reg += temp; inst_cycles += 4; } else gb->cpu_reg.pc.reg++; break; case 0x31: /* LD SP, imm */ gb->cpu_reg.sp.bytes.p = __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.sp.bytes.s = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x32: /* LD (HL), A */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.a); gb->cpu_reg.hl.reg--; break; case 0x33: /* INC SP */ gb->cpu_reg.sp.reg++; break; case 0x34: /* INC (HL) */ { uint8_t temp = __gb_read(gb, gb->cpu_reg.hl.reg) + 1; gb->cpu_reg.f_bits.z = (temp == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((temp & 0x0F) == 0x00); __gb_write(gb, gb->cpu_reg.hl.reg, temp); break; } case 0x35: /* DEC (HL) */ { uint8_t temp = __gb_read(gb, gb->cpu_reg.hl.reg) - 1; gb->cpu_reg.f_bits.z = (temp == 0x00); gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = ((temp & 0x0F) == 0x0F); __gb_write(gb, gb->cpu_reg.hl.reg, temp); break; } case 0x36: /* LD (HL), imm */ __gb_write(gb, gb->cpu_reg.hl.reg, __gb_read(gb, gb->cpu_reg.pc.reg++)); break; case 0x37: /* SCF */ gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 1; break; case 0x38: /* JP C, imm */ if(gb->cpu_reg.f_bits.c) { int8_t temp = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.pc.reg += temp; inst_cycles += 4; } else gb->cpu_reg.pc.reg++; break; case 0x39: /* ADD HL, SP */ { uint_fast32_t temp = gb->cpu_reg.hl.reg + gb->cpu_reg.sp.reg; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.hl.reg & 0xFFF) + (gb->cpu_reg.sp.reg & 0xFFF)) & 0x1000 ? 1 : 0; gb->cpu_reg.f_bits.c = temp & 0x10000 ? 1 : 0; gb->cpu_reg.hl.reg = (uint16_t)temp; break; } case 0x3A: /* LD A, (HL) */ gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.hl.reg--); break; case 0x3B: /* DEC SP */ gb->cpu_reg.sp.reg--; break; case 0x3C: /* INC A */ gb->cpu_reg.a++; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a & 0x0F) == 0x00); break; case 0x3D: /* DEC A */ gb->cpu_reg.a--; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.a & 0x0F) == 0x0F); break; case 0x3E: /* LD A, imm */ gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.pc.reg++); break; case 0x3F: /* CCF */ gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = ~gb->cpu_reg.f_bits.c; break; case 0x40: /* LD B, B */ break; case 0x41: /* LD B, C */ gb->cpu_reg.bc.bytes.b = gb->cpu_reg.bc.bytes.c; break; case 0x42: /* LD B, D */ gb->cpu_reg.bc.bytes.b = gb->cpu_reg.de.bytes.d; break; case 0x43: /* LD B, E */ gb->cpu_reg.bc.bytes.b = gb->cpu_reg.de.bytes.e; break; case 0x44: /* LD B, H */ gb->cpu_reg.bc.bytes.b = gb->cpu_reg.hl.bytes.h; break; case 0x45: /* LD B, L */ gb->cpu_reg.bc.bytes.b = gb->cpu_reg.hl.bytes.l; break; case 0x46: /* LD B, (HL) */ gb->cpu_reg.bc.bytes.b = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x47: /* LD B, A */ gb->cpu_reg.bc.bytes.b = gb->cpu_reg.a; break; case 0x48: /* LD C, B */ gb->cpu_reg.bc.bytes.c = gb->cpu_reg.bc.bytes.b; break; case 0x49: /* LD C, C */ break; case 0x4A: /* LD C, D */ gb->cpu_reg.bc.bytes.c = gb->cpu_reg.de.bytes.d; break; case 0x4B: /* LD C, E */ gb->cpu_reg.bc.bytes.c = gb->cpu_reg.de.bytes.e; break; case 0x4C: /* LD C, H */ gb->cpu_reg.bc.bytes.c = gb->cpu_reg.hl.bytes.h; break; case 0x4D: /* LD C, L */ gb->cpu_reg.bc.bytes.c = gb->cpu_reg.hl.bytes.l; break; case 0x4E: /* LD C, (HL) */ gb->cpu_reg.bc.bytes.c = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x4F: /* LD C, A */ gb->cpu_reg.bc.bytes.c = gb->cpu_reg.a; break; case 0x50: /* LD D, B */ gb->cpu_reg.de.bytes.d = gb->cpu_reg.bc.bytes.b; break; case 0x51: /* LD D, C */ gb->cpu_reg.de.bytes.d = gb->cpu_reg.bc.bytes.c; break; case 0x52: /* LD D, D */ break; case 0x53: /* LD D, E */ gb->cpu_reg.de.bytes.d = gb->cpu_reg.de.bytes.e; break; case 0x54: /* LD D, H */ gb->cpu_reg.de.bytes.d = gb->cpu_reg.hl.bytes.h; break; case 0x55: /* LD D, L */ gb->cpu_reg.de.bytes.d = gb->cpu_reg.hl.bytes.l; break; case 0x56: /* LD D, (HL) */ gb->cpu_reg.de.bytes.d = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x57: /* LD D, A */ gb->cpu_reg.de.bytes.d = gb->cpu_reg.a; break; case 0x58: /* LD E, B */ gb->cpu_reg.de.bytes.e = gb->cpu_reg.bc.bytes.b; break; case 0x59: /* LD E, C */ gb->cpu_reg.de.bytes.e = gb->cpu_reg.bc.bytes.c; break; case 0x5A: /* LD E, D */ gb->cpu_reg.de.bytes.e = gb->cpu_reg.de.bytes.d; break; case 0x5B: /* LD E, E */ break; case 0x5C: /* LD E, H */ gb->cpu_reg.de.bytes.e = gb->cpu_reg.hl.bytes.h; break; case 0x5D: /* LD E, L */ gb->cpu_reg.de.bytes.e = gb->cpu_reg.hl.bytes.l; break; case 0x5E: /* LD E, (HL) */ gb->cpu_reg.de.bytes.e = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x5F: /* LD E, A */ gb->cpu_reg.de.bytes.e = gb->cpu_reg.a; break; case 0x60: /* LD H, B */ gb->cpu_reg.hl.bytes.h = gb->cpu_reg.bc.bytes.b; break; case 0x61: /* LD H, C */ gb->cpu_reg.hl.bytes.h = gb->cpu_reg.bc.bytes.c; break; case 0x62: /* LD H, D */ gb->cpu_reg.hl.bytes.h = gb->cpu_reg.de.bytes.d; break; case 0x63: /* LD H, E */ gb->cpu_reg.hl.bytes.h = gb->cpu_reg.de.bytes.e; break; case 0x64: /* LD H, H */ break; case 0x65: /* LD H, L */ gb->cpu_reg.hl.bytes.h = gb->cpu_reg.hl.bytes.l; break; case 0x66: /* LD H, (HL) */ gb->cpu_reg.hl.bytes.h = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x67: /* LD H, A */ gb->cpu_reg.hl.bytes.h = gb->cpu_reg.a; break; case 0x68: /* LD L, B */ gb->cpu_reg.hl.bytes.l = gb->cpu_reg.bc.bytes.b; break; case 0x69: /* LD L, C */ gb->cpu_reg.hl.bytes.l = gb->cpu_reg.bc.bytes.c; break; case 0x6A: /* LD L, D */ gb->cpu_reg.hl.bytes.l = gb->cpu_reg.de.bytes.d; break; case 0x6B: /* LD L, E */ gb->cpu_reg.hl.bytes.l = gb->cpu_reg.de.bytes.e; break; case 0x6C: /* LD L, H */ gb->cpu_reg.hl.bytes.l = gb->cpu_reg.hl.bytes.h; break; case 0x6D: /* LD L, L */ break; case 0x6E: /* LD L, (HL) */ gb->cpu_reg.hl.bytes.l = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x6F: /* LD L, A */ gb->cpu_reg.hl.bytes.l = gb->cpu_reg.a; break; case 0x70: /* LD (HL), B */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.bc.bytes.b); break; case 0x71: /* LD (HL), C */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.bc.bytes.c); break; case 0x72: /* LD (HL), D */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.de.bytes.d); break; case 0x73: /* LD (HL), E */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.de.bytes.e); break; case 0x74: /* LD (HL), H */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.hl.bytes.h); break; case 0x75: /* LD (HL), L */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.hl.bytes.l); break; case 0x76: /* HALT */ { int_fast16_t halt_cycles = INT_FAST16_MAX; /* TODO: Emulate HALT bug? */ gb->gb_halt = 1; if (gb->hram_io[IO_IE] == 0) { /* Return program counter where this halt forever state started. */ /* This may be intentional, but this is required to stop an infinite * loop. */ (gb->gb_error)(gb, GB_HALT_FOREVER, gb->cpu_reg.pc.reg - 1); PGB_UNREACHABLE(); } if(gb->hram_io[IO_SC] & SERIAL_SC_TX_START) { int serial_cycles = SERIAL_CYCLES - gb->counter.serial_count; if(serial_cycles < halt_cycles) halt_cycles = serial_cycles; } if(gb->hram_io[IO_TAC] & IO_TAC_ENABLE_MASK) { int tac_cycles = TAC_CYCLES[gb->hram_io[IO_TAC] & IO_TAC_RATE_MASK] - gb->counter.tima_count; if(tac_cycles < halt_cycles) halt_cycles = tac_cycles; } if((gb->hram_io[IO_LCDC] & LCDC_ENABLE) != 0) { int lcd_cycles; if((gb->hram_io[IO_STAT] & STAT_MODE) == IO_STAT_MODE_SEARCH_OAM) { lcd_cycles = LCD_MODE_3_CYCLES - gb->counter.lcd_count; } else if((gb->hram_io[IO_STAT] & STAT_MODE) == IO_STAT_MODE_HBLANK) { lcd_cycles = LCD_MODE_2_CYCLES - gb->counter.lcd_count; } else { lcd_cycles = LCD_LINE_CYCLES - gb->counter.lcd_count; } if(lcd_cycles < halt_cycles) halt_cycles = lcd_cycles; } /* Some halt cycles may already be very high, so make sure we * don't underflow here. */ if(halt_cycles <= 0) halt_cycles = 4; inst_cycles = (uint_fast16_t)halt_cycles; break; } case 0x77: /* LD (HL), A */ __gb_write(gb, gb->cpu_reg.hl.reg, gb->cpu_reg.a); break; case 0x78: /* LD A, B */ gb->cpu_reg.a = gb->cpu_reg.bc.bytes.b; break; case 0x79: /* LD A, C */ gb->cpu_reg.a = gb->cpu_reg.bc.bytes.c; break; case 0x7A: /* LD A, D */ gb->cpu_reg.a = gb->cpu_reg.de.bytes.d; break; case 0x7B: /* LD A, E */ gb->cpu_reg.a = gb->cpu_reg.de.bytes.e; break; case 0x7C: /* LD A, H */ gb->cpu_reg.a = gb->cpu_reg.hl.bytes.h; break; case 0x7D: /* LD A, L */ gb->cpu_reg.a = gb->cpu_reg.hl.bytes.l; break; case 0x7E: /* LD A, (HL) */ gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.hl.reg); break; case 0x7F: /* LD A, A */ break; case 0x80: /* ADD A, B */ PGB_INSTR_ADC_R8(gb->cpu_reg.bc.bytes.b, 0); break; case 0x81: /* ADD A, C */ PGB_INSTR_ADC_R8(gb->cpu_reg.bc.bytes.c, 0); break; case 0x82: /* ADD A, D */ PGB_INSTR_ADC_R8(gb->cpu_reg.de.bytes.d, 0); break; case 0x83: /* ADD A, E */ PGB_INSTR_ADC_R8(gb->cpu_reg.de.bytes.e, 0); break; case 0x84: /* ADD A, H */ PGB_INSTR_ADC_R8(gb->cpu_reg.hl.bytes.h, 0); break; case 0x85: /* ADD A, L */ PGB_INSTR_ADC_R8(gb->cpu_reg.hl.bytes.l, 0); break; case 0x86: /* ADD A, (HL) */ { uint8_t val = __gb_read(gb, gb->cpu_reg.hl.reg); PGB_INSTR_ADC_R8(val, 0); break; } case 0x87: /* ADD A, A */ PGB_INSTR_ADC_R8(gb->cpu_reg.a, 0); break; case 0x88: /* ADC A, B */ PGB_INSTR_ADC_R8(gb->cpu_reg.bc.bytes.b, gb->cpu_reg.f_bits.c); break; case 0x89: /* ADC A, C */ PGB_INSTR_ADC_R8(gb->cpu_reg.bc.bytes.c, gb->cpu_reg.f_bits.c); break; case 0x8A: /* ADC A, D */ PGB_INSTR_ADC_R8(gb->cpu_reg.de.bytes.d, gb->cpu_reg.f_bits.c); break; case 0x8B: /* ADC A, E */ PGB_INSTR_ADC_R8(gb->cpu_reg.de.bytes.e, gb->cpu_reg.f_bits.c); break; case 0x8C: /* ADC A, H */ PGB_INSTR_ADC_R8(gb->cpu_reg.hl.bytes.h, gb->cpu_reg.f_bits.c); break; case 0x8D: /* ADC A, L */ PGB_INSTR_ADC_R8(gb->cpu_reg.hl.bytes.l, gb->cpu_reg.f_bits.c); break; case 0x8E: /* ADC A, (HL) */ { uint8_t val = __gb_read(gb, gb->cpu_reg.hl.reg); PGB_INSTR_ADC_R8(val, gb->cpu_reg.f_bits.c); break; } case 0x8F: /* ADC A, A */ PGB_INSTR_ADC_R8(gb->cpu_reg.a, gb->cpu_reg.f_bits.c); break; case 0x90: /* SUB B */ PGB_INSTR_SBC_R8(gb->cpu_reg.bc.bytes.b, 0); break; case 0x91: /* SUB C */ PGB_INSTR_SBC_R8(gb->cpu_reg.bc.bytes.c, 0); break; case 0x92: /* SUB D */ PGB_INSTR_SBC_R8(gb->cpu_reg.de.bytes.d, 0); break; case 0x93: /* SUB E */ PGB_INSTR_SBC_R8(gb->cpu_reg.de.bytes.e, 0); break; case 0x94: /* SUB H */ PGB_INSTR_SBC_R8(gb->cpu_reg.hl.bytes.h, 0); break; case 0x95: /* SUB L */ PGB_INSTR_SBC_R8(gb->cpu_reg.hl.bytes.l, 0); break; case 0x96: /* SUB (HL) */ { uint8_t val = __gb_read(gb, gb->cpu_reg.hl.reg); PGB_INSTR_SBC_R8(val, 0); break; } case 0x97: /* SUB A */ gb->cpu_reg.a = 0; gb->cpu_reg.f_bits.z = 1; gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0x98: /* SBC A, B */ PGB_INSTR_SBC_R8(gb->cpu_reg.bc.bytes.b, gb->cpu_reg.f_bits.c); break; case 0x99: /* SBC A, C */ PGB_INSTR_SBC_R8(gb->cpu_reg.bc.bytes.c, gb->cpu_reg.f_bits.c); break; case 0x9A: /* SBC A, D */ PGB_INSTR_SBC_R8(gb->cpu_reg.de.bytes.d, gb->cpu_reg.f_bits.c); break; case 0x9B: /* SBC A, E */ PGB_INSTR_SBC_R8(gb->cpu_reg.de.bytes.e, gb->cpu_reg.f_bits.c); break; case 0x9C: /* SBC A, H */ PGB_INSTR_SBC_R8(gb->cpu_reg.hl.bytes.h, gb->cpu_reg.f_bits.c); break; case 0x9D: /* SBC A, L */ PGB_INSTR_SBC_R8(gb->cpu_reg.hl.bytes.l, gb->cpu_reg.f_bits.c); break; case 0x9E: /* SBC A, (HL) */ { uint8_t val = __gb_read(gb, gb->cpu_reg.hl.reg); PGB_INSTR_SBC_R8(val, gb->cpu_reg.f_bits.c); break; } case 0x9F: /* SBC A, A */ gb->cpu_reg.a = gb->cpu_reg.f_bits.c ? 0xFF : 0x00; gb->cpu_reg.f_bits.z = !gb->cpu_reg.f_bits.c; gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = gb->cpu_reg.f_bits.c; break; case 0xA0: /* AND B */ gb->cpu_reg.a = gb->cpu_reg.a & gb->cpu_reg.bc.bytes.b; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA1: /* AND C */ gb->cpu_reg.a = gb->cpu_reg.a & gb->cpu_reg.bc.bytes.c; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA2: /* AND D */ gb->cpu_reg.a = gb->cpu_reg.a & gb->cpu_reg.de.bytes.d; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA3: /* AND E */ gb->cpu_reg.a = gb->cpu_reg.a & gb->cpu_reg.de.bytes.e; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA4: /* AND H */ gb->cpu_reg.a = gb->cpu_reg.a & gb->cpu_reg.hl.bytes.h; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA5: /* AND L */ gb->cpu_reg.a = gb->cpu_reg.a & gb->cpu_reg.hl.bytes.l; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA6: /* AND (HL) */ gb->cpu_reg.a = gb->cpu_reg.a & __gb_read(gb, gb->cpu_reg.hl.reg); gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA7: /* AND A */ gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xA8: /* XOR B */ gb->cpu_reg.a = gb->cpu_reg.a ^ gb->cpu_reg.bc.bytes.b; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xA9: /* XOR C */ gb->cpu_reg.a = gb->cpu_reg.a ^ gb->cpu_reg.bc.bytes.c; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xAA: /* XOR D */ gb->cpu_reg.a = gb->cpu_reg.a ^ gb->cpu_reg.de.bytes.d; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xAB: /* XOR E */ gb->cpu_reg.a = gb->cpu_reg.a ^ gb->cpu_reg.de.bytes.e; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xAC: /* XOR H */ gb->cpu_reg.a = gb->cpu_reg.a ^ gb->cpu_reg.hl.bytes.h; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xAD: /* XOR L */ gb->cpu_reg.a = gb->cpu_reg.a ^ gb->cpu_reg.hl.bytes.l; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xAE: /* XOR (HL) */ gb->cpu_reg.a = gb->cpu_reg.a ^ __gb_read(gb, gb->cpu_reg.hl.reg); gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xAF: /* XOR A */ gb->cpu_reg.a = 0x00; gb->cpu_reg.f_bits.z = 1; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB0: /* OR B */ gb->cpu_reg.a = gb->cpu_reg.a | gb->cpu_reg.bc.bytes.b; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB1: /* OR C */ gb->cpu_reg.a = gb->cpu_reg.a | gb->cpu_reg.bc.bytes.c; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB2: /* OR D */ gb->cpu_reg.a = gb->cpu_reg.a | gb->cpu_reg.de.bytes.d; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB3: /* OR E */ gb->cpu_reg.a = gb->cpu_reg.a | gb->cpu_reg.de.bytes.e; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB4: /* OR H */ gb->cpu_reg.a = gb->cpu_reg.a | gb->cpu_reg.hl.bytes.h; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB5: /* OR L */ gb->cpu_reg.a = gb->cpu_reg.a | gb->cpu_reg.hl.bytes.l; gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB6: /* OR (HL) */ gb->cpu_reg.a = gb->cpu_reg.a | __gb_read(gb, gb->cpu_reg.hl.reg); gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB7: /* OR A */ gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xB8: /* CP B */ PGB_INSTR_CP_R8(gb->cpu_reg.bc.bytes.b); break; case 0xB9: /* CP C */ PGB_INSTR_CP_R8(gb->cpu_reg.bc.bytes.c); break; case 0xBA: /* CP D */ PGB_INSTR_CP_R8(gb->cpu_reg.de.bytes.d); break; case 0xBB: /* CP E */ PGB_INSTR_CP_R8(gb->cpu_reg.de.bytes.e); break; case 0xBC: /* CP H */ PGB_INSTR_CP_R8(gb->cpu_reg.hl.bytes.h); break; case 0xBD: /* CP L */ PGB_INSTR_CP_R8(gb->cpu_reg.hl.bytes.l); break; case 0xBE: /* CP (HL) */ { uint8_t val = __gb_read(gb, gb->cpu_reg.hl.reg); PGB_INSTR_CP_R8(val); break; } case 0xBF: /* CP A */ gb->cpu_reg.f_bits.z = 1; gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xC0: /* RET NZ */ if(!gb->cpu_reg.f_bits.z) { gb->cpu_reg.pc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.pc.bytes.p = __gb_read(gb, gb->cpu_reg.sp.reg++); inst_cycles += 12; } break; case 0xC1: /* POP BC */ gb->cpu_reg.bc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.bc.bytes.b = __gb_read(gb, gb->cpu_reg.sp.reg++); break; case 0xC2: /* JP NZ, imm */ if(!gb->cpu_reg.f_bits.z) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 4; } else gb->cpu_reg.pc.reg += 2; break; case 0xC3: /* JP imm */ { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; break; } case 0xC4: /* CALL NZ imm */ if(!gb->cpu_reg.f_bits.z) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg++); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 12; } else gb->cpu_reg.pc.reg += 2; break; case 0xC5: /* PUSH BC */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.bc.bytes.b); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.bc.bytes.c); break; case 0xC6: /* ADD A, imm */ { uint8_t val = __gb_read(gb, gb->cpu_reg.pc.reg++); PGB_INSTR_ADC_R8(val, 0); break; } case 0xC7: /* RST 0x0000 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0000; break; case 0xC8: /* RET Z */ if(gb->cpu_reg.f_bits.z) { gb->cpu_reg.pc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.pc.bytes.p = __gb_read(gb, gb->cpu_reg.sp.reg++); inst_cycles += 12; } break; case 0xC9: /* RET */ { gb->cpu_reg.pc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.pc.bytes.p = __gb_read(gb, gb->cpu_reg.sp.reg++); break; } case 0xCA: /* JP Z, imm */ if(gb->cpu_reg.f_bits.z) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 4; } else gb->cpu_reg.pc.reg += 2; break; case 0xCB: /* CB INST */ inst_cycles = __gb_execute_cb(gb); break; case 0xCC: /* CALL Z, imm */ if(gb->cpu_reg.f_bits.z) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg++); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 12; } else gb->cpu_reg.pc.reg += 2; break; case 0xCD: /* CALL imm */ { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg++); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; } break; case 0xCE: /* ADC A, imm */ { uint8_t val = __gb_read(gb, gb->cpu_reg.pc.reg++); PGB_INSTR_ADC_R8(val, gb->cpu_reg.f_bits.c); break; } case 0xCF: /* RST 0x0008 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0008; break; case 0xD0: /* RET NC */ if(!gb->cpu_reg.f_bits.c) { gb->cpu_reg.pc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.pc.bytes.p = __gb_read(gb, gb->cpu_reg.sp.reg++); inst_cycles += 12; } break; case 0xD1: /* POP DE */ gb->cpu_reg.de.bytes.e = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.de.bytes.d = __gb_read(gb, gb->cpu_reg.sp.reg++); break; case 0xD2: /* JP NC, imm */ if(!gb->cpu_reg.f_bits.c) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 4; } else gb->cpu_reg.pc.reg += 2; break; case 0xD4: /* CALL NC, imm */ if(!gb->cpu_reg.f_bits.c) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg++); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 12; } else gb->cpu_reg.pc.reg += 2; break; case 0xD5: /* PUSH DE */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.de.bytes.d); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.de.bytes.e); break; case 0xD6: /* SUB imm */ { uint8_t val = __gb_read(gb, gb->cpu_reg.pc.reg++); uint16_t temp = gb->cpu_reg.a - val; gb->cpu_reg.f_bits.z = ((temp & 0xFF) == 0x00); gb->cpu_reg.f_bits.n = 1; gb->cpu_reg.f_bits.h = (gb->cpu_reg.a ^ val ^ temp) & 0x10 ? 1 : 0; gb->cpu_reg.f_bits.c = (temp & 0xFF00) ? 1 : 0; gb->cpu_reg.a = (temp & 0xFF); break; } case 0xD7: /* RST 0x0010 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0010; break; case 0xD8: /* RET C */ if(gb->cpu_reg.f_bits.c) { gb->cpu_reg.pc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.pc.bytes.p = __gb_read(gb, gb->cpu_reg.sp.reg++); inst_cycles += 12; } break; case 0xD9: /* RETI */ { gb->cpu_reg.pc.bytes.c = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.pc.bytes.p = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->gb_ime = 1; } break; case 0xDA: /* JP C, imm */ if(gb->cpu_reg.f_bits.c) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 4; } else gb->cpu_reg.pc.reg += 2; break; case 0xDC: /* CALL C, imm */ if(gb->cpu_reg.f_bits.c) { uint8_t p, c; c = __gb_read(gb, gb->cpu_reg.pc.reg++); p = __gb_read(gb, gb->cpu_reg.pc.reg++); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.bytes.c = c; gb->cpu_reg.pc.bytes.p = p; inst_cycles += 12; } else gb->cpu_reg.pc.reg += 2; break; case 0xDE: /* SBC A, imm */ { uint8_t val = __gb_read(gb, gb->cpu_reg.pc.reg++); PGB_INSTR_SBC_R8(val, gb->cpu_reg.f_bits.c); break; } case 0xDF: /* RST 0x0018 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0018; break; case 0xE0: /* LD (0xFF00+imm), A */ __gb_write(gb, 0xFF00 | __gb_read(gb, gb->cpu_reg.pc.reg++), gb->cpu_reg.a); break; case 0xE1: /* POP HL */ gb->cpu_reg.hl.bytes.l = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.hl.bytes.h = __gb_read(gb, gb->cpu_reg.sp.reg++); break; case 0xE2: /* LD (C), A */ __gb_write(gb, 0xFF00 | gb->cpu_reg.bc.bytes.c, gb->cpu_reg.a); break; case 0xE5: /* PUSH HL */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.hl.bytes.h); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.hl.bytes.l); break; case 0xE6: /* AND imm */ /* TODO: Optimisation? */ gb->cpu_reg.a = gb->cpu_reg.a & __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 0; break; case 0xE7: /* RST 0x0020 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0020; break; case 0xE8: /* ADD SP, imm */ { int8_t offset = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.f_bits.z = 0; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.sp.reg & 0xF) + (offset & 0xF) > 0xF) ? 1 : 0; gb->cpu_reg.f_bits.c = ((gb->cpu_reg.sp.reg & 0xFF) + (offset & 0xFF) > 0xFF); gb->cpu_reg.sp.reg += offset; break; } case 0xE9: /* JP (HL) */ gb->cpu_reg.pc.reg = gb->cpu_reg.hl.reg; break; case 0xEA: /* LD (imm), A */ { uint8_t h, l; uint16_t addr; l = __gb_read(gb, gb->cpu_reg.pc.reg++); h = __gb_read(gb, gb->cpu_reg.pc.reg++); addr = PEANUT_GB_U8_TO_U16(h, l); __gb_write(gb, addr, gb->cpu_reg.a); break; } case 0xEE: /* XOR imm */ gb->cpu_reg.a = gb->cpu_reg.a ^ __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xEF: /* RST 0x0028 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0028; break; case 0xF0: /* LD A, (0xFF00+imm) */ gb->cpu_reg.a = __gb_read(gb, 0xFF00 | __gb_read(gb, gb->cpu_reg.pc.reg++)); break; case 0xF1: /* POP AF */ { uint8_t temp_8 = __gb_read(gb, gb->cpu_reg.sp.reg++); gb->cpu_reg.f_bits.z = (temp_8 >> 7) & 1; gb->cpu_reg.f_bits.n = (temp_8 >> 6) & 1; gb->cpu_reg.f_bits.h = (temp_8 >> 5) & 1; gb->cpu_reg.f_bits.c = (temp_8 >> 4) & 1; gb->cpu_reg.a = __gb_read(gb, gb->cpu_reg.sp.reg++); break; } case 0xF2: /* LD A, (C) */ gb->cpu_reg.a = __gb_read(gb, 0xFF00 | gb->cpu_reg.bc.bytes.c); break; case 0xF3: /* DI */ gb->gb_ime = 0; break; case 0xF5: /* PUSH AF */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.a); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.f_bits.z << 7 | gb->cpu_reg.f_bits.n << 6 | gb->cpu_reg.f_bits.h << 5 | gb->cpu_reg.f_bits.c << 4); break; case 0xF6: /* OR imm */ gb->cpu_reg.a = gb->cpu_reg.a | __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.f_bits.z = (gb->cpu_reg.a == 0x00); gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 0; gb->cpu_reg.f_bits.c = 0; break; case 0xF7: /* PUSH AF */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0030; break; case 0xF8: /* LD HL, SP+/-imm */ { /* Taken from SameBoy, which is released under MIT Licence. */ int8_t offset = (int8_t) __gb_read(gb, gb->cpu_reg.pc.reg++); gb->cpu_reg.hl.reg = gb->cpu_reg.sp.reg + offset; gb->cpu_reg.f_bits.z = 0; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = ((gb->cpu_reg.sp.reg & 0xF) + (offset & 0xF) > 0xF) ? 1 : 0; gb->cpu_reg.f_bits.c = ((gb->cpu_reg.sp.reg & 0xFF) + (offset & 0xFF) > 0xFF) ? 1 : 0; break; } case 0xF9: /* LD SP, HL */ gb->cpu_reg.sp.reg = gb->cpu_reg.hl.reg; break; case 0xFA: /* LD A, (imm) */ { uint8_t h, l; uint16_t addr; l = __gb_read(gb, gb->cpu_reg.pc.reg++); h = __gb_read(gb, gb->cpu_reg.pc.reg++); addr = PEANUT_GB_U8_TO_U16(h, l); gb->cpu_reg.a = __gb_read(gb, addr); break; } case 0xFB: /* EI */ gb->gb_ime = 1; break; case 0xFE: /* CP imm */ { uint8_t val = __gb_read(gb, gb->cpu_reg.pc.reg++); PGB_INSTR_CP_R8(val); break; } case 0xFF: /* RST 0x0038 */ __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.p); __gb_write(gb, --gb->cpu_reg.sp.reg, gb->cpu_reg.pc.bytes.c); gb->cpu_reg.pc.reg = 0x0038; break; default: /* Return address where invlid opcode that was read. */ (gb->gb_error)(gb, GB_INVALID_OPCODE, gb->cpu_reg.pc.reg - 1); PGB_UNREACHABLE(); } do { /* DIV register timing */ gb->counter.div_count += inst_cycles; while(gb->counter.div_count >= DIV_CYCLES) { gb->hram_io[IO_DIV]++; gb->counter.div_count -= DIV_CYCLES; } /* Check serial transmission. */ if(gb->hram_io[IO_SC] & SERIAL_SC_TX_START) { /* If new transfer, call TX function. */ if(gb->counter.serial_count == 0 && gb->gb_serial_tx != NULL) (gb->gb_serial_tx)(gb, gb->hram_io[IO_SB]); gb->counter.serial_count += inst_cycles; /* If it's time to receive byte, call RX function. */ if(gb->counter.serial_count >= SERIAL_CYCLES) { /* If RX can be done, do it. */ /* If RX failed, do not change SB if using external * clock, or set to 0xFF if using internal clock. */ uint8_t rx; if(gb->gb_serial_rx != NULL && (gb->gb_serial_rx(gb, &rx) == GB_SERIAL_RX_SUCCESS)) { gb->hram_io[IO_SB] = rx; /* Inform game of serial TX/RX completion. */ gb->hram_io[IO_SC] &= 0x01; gb->hram_io[IO_IF] |= SERIAL_INTR; } else if(gb->hram_io[IO_SC] & SERIAL_SC_CLOCK_SRC) { /* If using internal clock, and console is not * attached to any external peripheral, shifted * bits are replaced with logic 1. */ gb->hram_io[IO_SB] = 0xFF; /* Inform game of serial TX/RX completion. */ gb->hram_io[IO_SC] &= 0x01; gb->hram_io[IO_IF] |= SERIAL_INTR; } else { /* If using external clock, and console is not * attached to any external peripheral, bits are * not shifted, so SB is not modified. */ } gb->counter.serial_count = 0; } } /* TIMA register timing */ /* TODO: Change tac_enable to struct of TAC timer control bits. */ if(gb->hram_io[IO_TAC] & IO_TAC_ENABLE_MASK) { gb->counter.tima_count += inst_cycles; while(gb->counter.tima_count >= TAC_CYCLES[gb->hram_io[IO_TAC] & IO_TAC_RATE_MASK]) { gb->counter.tima_count -= TAC_CYCLES[gb->hram_io[IO_TAC] & IO_TAC_RATE_MASK]; if(++gb->hram_io[IO_TIMA] == 0) { gb->hram_io[IO_IF] |= TIMER_INTR; /* On overflow, set TMA to TIMA. */ gb->hram_io[IO_TIMA] = gb->hram_io[IO_TMA]; } } } /* TODO Check behaviour of LCD during LCD power off state. */ /* If LCD is off, don't update LCD state. */ if((gb->hram_io[IO_LCDC] & LCDC_ENABLE) == 0) continue; /* LCD Timing */ gb->counter.lcd_count += inst_cycles; /* New Scanline */ if((gb->hram_io[IO_STAT] & STAT_MODE) & IO_STAT_MODE_VBLANK_OR_TRANSFER_MASK && gb->counter.lcd_count >= LCD_LINE_CYCLES) { gb->counter.lcd_count -= LCD_LINE_CYCLES; /* LYC Update */ if(gb->hram_io[IO_LY] == gb->hram_io[IO_LYC]) { gb->hram_io[IO_STAT] |= STAT_LYC_COINC; if(gb->hram_io[IO_STAT] & STAT_LYC_INTR) gb->hram_io[IO_IF] |= LCDC_INTR; } else gb->hram_io[IO_STAT] &= 0xFB; /* Next line */ gb->hram_io[IO_LY] = (gb->hram_io[IO_LY] + 1) % LCD_VERT_LINES; /* VBLANK Start */ if(gb->hram_io[IO_LY] == LCD_HEIGHT) { gb->hram_io[IO_STAT] = (gb->hram_io[IO_STAT] & ~STAT_MODE) | IO_STAT_MODE_VBLANK; gb->gb_frame = 1; gb->hram_io[IO_IF] |= VBLANK_INTR; gb->lcd_blank = 0; if(gb->hram_io[IO_STAT] & STAT_MODE_1_INTR) gb->hram_io[IO_IF] |= LCDC_INTR; #if ENABLE_LCD /* If frame skip is activated, check if we need to draw * the frame or skip it. */ if(gb->direct.frame_skip) { gb->display.frame_skip_count = !gb->display.frame_skip_count; } /* If interlaced is activated, change which lines get * updated. Also, only update lines on frames that are * actually drawn when frame skip is enabled. */ if(gb->direct.interlace && (!gb->direct.frame_skip || gb->display.frame_skip_count)) { gb->display.interlace_count = !gb->display.interlace_count; } #endif } /* Normal Line */ else if(gb->hram_io[IO_LY] < LCD_HEIGHT) { if(gb->hram_io[IO_LY] == 0) { /* Clear Screen */ gb->display.WY = gb->hram_io[IO_WY]; gb->display.window_clear = 0; } gb->hram_io[IO_STAT] = (gb->hram_io[IO_STAT] & ~STAT_MODE) | IO_STAT_MODE_HBLANK; if(gb->hram_io[IO_STAT] & STAT_MODE_0_INTR) gb->hram_io[IO_IF] |= LCDC_INTR; /* If halted immediately jump to next LCD mode. */ if(gb->counter.lcd_count < LCD_MODE_2_CYCLES) inst_cycles = LCD_MODE_2_CYCLES - gb->counter.lcd_count; } } /* OAM access */ else if((gb->hram_io[IO_STAT] & STAT_MODE) == IO_STAT_MODE_HBLANK && gb->counter.lcd_count >= LCD_MODE_2_CYCLES) { gb->hram_io[IO_STAT] = (gb->hram_io[IO_STAT] & ~STAT_MODE) | IO_STAT_MODE_SEARCH_OAM; if(gb->hram_io[IO_STAT] & STAT_MODE_2_INTR) gb->hram_io[IO_IF] |= LCDC_INTR; /* If halted immediately jump to next LCD mode. */ if (gb->counter.lcd_count < LCD_MODE_3_CYCLES) inst_cycles = LCD_MODE_3_CYCLES - gb->counter.lcd_count; } /* Update LCD */ else if((gb->hram_io[IO_STAT] & STAT_MODE) == IO_STAT_MODE_SEARCH_OAM && gb->counter.lcd_count >= LCD_MODE_3_CYCLES) { gb->hram_io[IO_STAT] = (gb->hram_io[IO_STAT] & ~STAT_MODE) | IO_STAT_MODE_SEARCH_TRANSFER; #if ENABLE_LCD if(!gb->lcd_blank) __gb_draw_line(gb); #endif /* If halted immediately jump to next LCD mode. */ if (gb->counter.lcd_count < LCD_LINE_CYCLES) inst_cycles = LCD_LINE_CYCLES - gb->counter.lcd_count; } } while(gb->gb_halt && (gb->hram_io[IO_IF] & gb->hram_io[IO_IE]) == 0); /* If halted, loop until an interrupt occurs. */ } void gb_run_frame(struct gb_s *gb) { gb->gb_frame = 0; while(!gb->gb_frame) __gb_step_cpu(gb); } /** * Gets the size of the save file required for the ROM. */ uint_fast32_t gb_get_save_size(struct gb_s *gb) { const uint_fast16_t ram_size_location = 0x0149; const uint_fast32_t ram_sizes[] = { 0x00, 0x800, 0x2000, 0x8000, 0x20000 }; uint8_t ram_size = gb->gb_rom_read(gb, ram_size_location); return ram_sizes[ram_size]; } void gb_init_serial(struct gb_s *gb, void (*gb_serial_tx)(struct gb_s*, const uint8_t), enum gb_serial_rx_ret_e (*gb_serial_rx)(struct gb_s*, uint8_t*)) { gb->gb_serial_tx = gb_serial_tx; gb->gb_serial_rx = gb_serial_rx; } uint8_t gb_colour_hash(struct gb_s *gb) { #define ROM_TITLE_START_ADDR 0x0134 #define ROM_TITLE_END_ADDR 0x0143 uint8_t x = 0; for(uint16_t i = ROM_TITLE_START_ADDR; i <= ROM_TITLE_END_ADDR; i++) x += gb->gb_rom_read(gb, i); return x; } /** * Resets the context, and initialises startup values. */ void gb_reset(struct gb_s *gb) { gb->gb_halt = 0; gb->gb_ime = 1; #if PEANUT_GB_USE_BIOS gb->gb_bios_enable = 0; #endif /* Initialise MBC values. */ gb->selected_rom_bank = 1; gb->cart_ram_bank = 0; gb->enable_cart_ram = 0; gb->cart_mode_select = 0; /* Initialise CPU registers as though a DMG. */ gb->cpu_reg.a = 0x01; gb->cpu_reg.f_bits.z = 1; gb->cpu_reg.f_bits.n = 0; gb->cpu_reg.f_bits.h = 1; gb->cpu_reg.f_bits.c = 1; gb->cpu_reg.bc.reg = 0x0013; gb->cpu_reg.de.reg = 0x00D8; gb->cpu_reg.hl.reg = 0x014D; gb->cpu_reg.sp.reg = 0xFFFE; /* TODO: Add BIOS support. */ gb->cpu_reg.pc.reg = 0x0100; gb->counter.lcd_count = 0; gb->counter.div_count = 0; gb->counter.tima_count = 0; gb->counter.serial_count = 0; memset(gb->hram_io, 0xFF, HRAM_IO_SIZE); gb->hram_io[IO_TIMA] = 0x00; gb->hram_io[IO_TMA ] = 0x00; gb->hram_io[IO_TAC ] = 0xF8; gb->hram_io[IO_DIV ] = 0xAC; gb->hram_io[IO_IF ] = 0xE1; gb->hram_io[IO_LCDC] = 0x91; gb->hram_io[IO_STAT] = STAT_MODE & IO_STAT_MODE_HBLANK; gb->hram_io[IO_SCY ] = 0x00; gb->hram_io[IO_SCX ] = 0x00; gb->hram_io[IO_LYC ] = 0x00; /* Appease valgrind for invalid reads and unconditional jumps. */ gb->hram_io[IO_SC] = 0x7E; gb->hram_io[IO_LY] = 0; __gb_write(gb, 0xFF47, 0xFC); // BGP __gb_write(gb, 0xFF48, 0xFF); // OBJP0 __gb_write(gb, 0xFF49, 0x0F); // OBJP1 gb->hram_io[IO_WY] = 0x00; gb->hram_io[IO_WX] = 0x00; gb->hram_io[IO_IE] = 0x00; gb->direct.joypad = 0xFF; gb->hram_io[IO_JOYP] = 0xCF; memset(gb->vram, 0x00, VRAM_SIZE); } enum gb_init_error_e gb_init(struct gb_s *gb, uint8_t (*gb_rom_read)(struct gb_s*, const uint_fast32_t), uint8_t (*gb_cart_ram_read)(struct gb_s*, const uint_fast32_t), void (*gb_cart_ram_write)(struct gb_s*, const uint_fast32_t, const uint8_t), void (*gb_error)(struct gb_s*, const enum gb_error_e, const uint16_t), void *priv) { const uint16_t mbc_location = 0x0147; const uint16_t bank_count_location = 0x0148; const uint16_t ram_size_location = 0x0149; /** * Table for cartridge type (MBC). -1 if invalid. * TODO: MMM01 is untested. * TODO: MBC6 is untested. * TODO: MBC7 is unsupported. * TODO: POCKET CAMERA is unsupported. * TODO: BANDAI TAMA5 is unsupported. * TODO: HuC3 is unsupported. * TODO: HuC1 is unsupported. **/ const int8_t cart_mbc[] = { 0, 1, 1, 1, -1, 2, 2, -1, 0, 0, -1, 0, 0, 0, -1, 3, 3, 3, 3, 3, -1, -1, -1, -1, -1, 5, 5, 5, 5, 5, 5, -1 }; const uint8_t cart_ram[] = { 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0 }; const uint16_t num_rom_banks_mask[] = { 2, 4, 8, 16, 32, 64, 128, 256, 512 }; const uint8_t num_ram_banks[] = { 0, 1, 1, 4, 16, 8 }; gb->gb_rom_read = gb_rom_read; gb->gb_cart_ram_read = gb_cart_ram_read; gb->gb_cart_ram_write = gb_cart_ram_write; gb->gb_error = gb_error; gb->direct.priv = priv; /* Initialise serial transfer function to NULL. If the front-end does * not provide serial support, Peanut-GB will emulate no cable connected * automatically. */ gb->gb_serial_tx = NULL; gb->gb_serial_rx = NULL; /* Check valid ROM using checksum value. */ { uint8_t x = 0; for(uint16_t i = 0x0134; i <= 0x014C; i++) x = x - gb->gb_rom_read(gb, i) - 1; if(x != gb->gb_rom_read(gb, ROM_HEADER_CHECKSUM_LOC)) return GB_INIT_INVALID_CHECKSUM; } /* Check if cartridge type is supported, and set MBC type. */ { const uint8_t mbc_value = gb->gb_rom_read(gb, mbc_location); if(mbc_value > sizeof(cart_mbc) - 1 || (gb->mbc = cart_mbc[mbc_value]) == -1) return GB_INIT_CARTRIDGE_UNSUPPORTED; } gb->cart_ram = cart_ram[gb->gb_rom_read(gb, mbc_location)]; gb->num_rom_banks_mask = num_rom_banks_mask[gb->gb_rom_read(gb, bank_count_location)] - 1; gb->num_ram_banks = num_ram_banks[gb->gb_rom_read(gb, ram_size_location)]; gb->lcd_blank = 0; gb->display.lcd_draw_line = NULL; gb_reset(gb); return GB_INIT_NO_ERROR; } const char* gb_get_rom_name(struct gb_s* gb, char *title_str) { uint_fast16_t title_loc = 0x134; /* End of title may be 0x13E for newer games. */ const uint_fast16_t title_end = 0x143; const char* title_start = title_str; for(; title_loc <= title_end; title_loc++) { const char title_char = gb->gb_rom_read(gb, title_loc); if(title_char >= ' ' && title_char <= '_') { *title_str = title_char; title_str++; } else break; } *title_str = '\0'; return title_start; } #if ENABLE_LCD void gb_init_lcd(struct gb_s *gb, void (*lcd_draw_line)(struct gb_s *gb, const uint8_t *pixels, const uint_fast8_t line)) { gb->display.lcd_draw_line = lcd_draw_line; gb->direct.interlace = 0; gb->display.interlace_count = 0; gb->direct.frame_skip = 0; gb->display.frame_skip_count = 0; gb->display.window_clear = 0; gb->display.WY = 0; return; } #endif /** * This was taken from SameBoy, which is released under MIT Licence. */ void gb_tick_rtc(struct gb_s *gb) { /* is timer running? */ if((gb->cart_rtc[4] & 0x40) == 0) { if(++gb->rtc_bits.sec == 60) { gb->rtc_bits.sec = 0; if(++gb->rtc_bits.min == 60) { gb->rtc_bits.min = 0; if(++gb->rtc_bits.hour == 24) { gb->rtc_bits.hour = 0; if(++gb->rtc_bits.yday == 0) { if(gb->rtc_bits.high & 1) /* Bit 8 of days*/ { gb->rtc_bits.high |= 0x80; /* Overflow bit */ } gb->rtc_bits.high ^= 1; } } } } } } void gb_set_rtc(struct gb_s *gb, const struct tm * const time) { gb->cart_rtc[0] = time->tm_sec; gb->cart_rtc[1] = time->tm_min; gb->cart_rtc[2] = time->tm_hour; gb->cart_rtc[3] = time->tm_yday & 0xFF; /* Low 8 bits of day counter. */ gb->cart_rtc[4] = time->tm_yday >> 8; /* High 1 bit of day counter. */ } /** Function prototypes: Required functions **/ /** * Initialises the emulator context to a known state. Call this before calling * any other peanut-gb function. * To reset the emulator, you can call gb_reset() instead. * * \param gb Allocated emulator context. Must not be NULL. * \param gb_rom_read Pointer to function that reads ROM data. ROM banking is * already handled by Peanut-GB. Must not be NULL. * \param gb_cart_ram_read Pointer to function that reads Cart RAM. Must not be * NULL. * \param gb_cart_ram_write Pointer to function to writes to Cart RAM. Must not * be NULL. * \param gb_error Pointer to function that is called when an unrecoverable * error occurs. Must not be NULL. Returning from this * function is undefined and will result in SIGABRT. * \param priv Private data that is stored within the emulator context. Set to * NULL if unused. * \returns 0 on success or an enum that describes the error. */ enum gb_init_error_e gb_init(struct gb_s *gb, uint8_t (*gb_rom_read)(struct gb_s*, const uint_fast32_t), uint8_t (*gb_cart_ram_read)(struct gb_s*, const uint_fast32_t), void (*gb_cart_ram_write)(struct gb_s*, const uint_fast32_t, const uint8_t), void (*gb_error)(struct gb_s*, const enum gb_error_e, const uint16_t), void *priv); /** * Executes the emulator and runs for one frame. * * \param An initialised emulator context. Must not be NULL. */ void gb_run_frame(struct gb_s *gb); /** Function prototypes: Optional Functions **/ /** * Reset the emulator, like turning the Game Boy off and on again. * This function can be called at any time. * * \param An initialised emulator context. Must not be NULL. */ void gb_reset(struct gb_s *gb); /** * Initialises the display context of the emulator. Only available when * ENABLE_LCD is defined to a non-zero value. * The pixel data sent to lcd_draw_line comes with both shade and layer data. * The first two least significant bits are the shade data (black, dark, light, * white). Bits 4 and 5 are layer data (OBJ0, OBJ1, BG), which can be used to * add more colours to the game in the same way that the Game Boy Color does to * older Game Boy games. * This function can be called at any time. * * \param gb An initialised emulator context. Must not be NULL. * \param lcd_draw_line Pointer to function that draws the 2-bit pixel data on the line * "line". Must not be NULL. */ #if ENABLE_LCD void gb_init_lcd(struct gb_s *gb, void (*lcd_draw_line)(struct gb_s *gb, const uint8_t *pixels, const uint_fast8_t line)); #endif /** * Initialises the serial connection of the emulator. This function is optional, * and if not called, the emulator will assume that no link cable is connected * to the game. * * \param gb An initialised emulator context. Must not be NULL. * \param gb_serial_tx Pointer to function that transmits a byte of data over * the serial connection. Must not be NULL. * \param gb_serial_rx Pointer to function that receives a byte of data over the * serial connection. If no byte is recieved, * return GB_SERIAL_RX_NO_CONNECTION. Must not be NULL. */ void gb_init_serial(struct gb_s *gb, void (*gb_serial_tx)(struct gb_s*, const uint8_t), enum gb_serial_rx_ret_e (*gb_serial_rx)(struct gb_s*, uint8_t*)); /** * Obtains the save size of the game (size of the Cart RAM). Required by the * frontend to allocate enough memory for the Cart RAM. * * \param gb An initialised emulator context. Must not be NULL. * \returns Size of the Cart RAM in bytes. 0 if Cartridge has not battery * backed RAM. */ uint_fast32_t gb_get_save_size(struct gb_s *gb); /** * Calculates and returns a hash of the game header in the same way the Game * Boy Color does for colourising old Game Boy games. The frontend can use this * hash to automatically set a colour palette. * * \param gb An initialised emulator context. Must not be NULL. * \returns Hash of the game header. */ uint8_t gb_colour_hash(struct gb_s *gb); /** * Returns the title of ROM. * * \param gb An initialised emulator context. Must not be NULL. * \param title_str Allocated string at least 16 characters. * \returns Pointer to start of string, null terminated. */ const char* gb_get_rom_name(struct gb_s* gb, char *title_str); /** * Tick the internal RTC by one second. This does not affect games with no RTC * support. * * \param gb An initialised emulator context. Must not be NULL. */ void gb_tick_rtc(struct gb_s *gb); /** * Set initial values in RTC. * Should be called after gb_init(). * * \param gb An initialised emulator context. Must not be NULL. * \param time Time structure with date and time. */ void gb_set_rtc(struct gb_s *gb, const struct tm * const time); /* Undefine CPU Flag helper functions. */ #undef PEANUT_GB_CPUFLAG_MASK_CARRY #undef PEANUT_GB_CPUFLAG_MASK_HALFC #undef PEANUT_GB_CPUFLAG_MASK_ARITH #undef PEANUT_GB_CPUFLAG_MASK_ZERO #undef PEANUT_GB_CPUFLAG_BIT_CARRY #undef PEANUT_GB_CPUFLAG_BIT_HALFC #undef PEANUT_GB_CPUFLAG_BIT_ARITH #undef PEANUT_GB_CPUFLAG_BIT_ZERO #undef PGB_SET_CARRY #undef PGB_SET_HALFC #undef PGB_SET_ARITH #undef PGB_SET_ZERO #undef PGB_GET_CARRY #undef PGB_GET_HALFC #undef PGB_GET_ARITH #undef PGB_GET_ZERO #endif //PEANUT_GB_H