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Fixed halt bug that caused the baground to be painted incorrectly dur…
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@Dhole
Dhole committed Jan 21, 2015
1 parent 7286525 commit cb3371c
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Showing 6 changed files with 75 additions and 42 deletions.
2 changes: 1 addition & 1 deletion dmg.c
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Original file line number Diff line number Diff line change
Expand Up @@ -152,7 +152,7 @@ uint32_t dmg_run(uint32_t delta, uint8_t *keypad, int *debug_flag, int *debug_pa
keypad_emulate(keypad);
//
// If LCD on...!!!
if(screen_emulate(cycles)) {
if (screen_emulate(cycles)) {
break;
}
}
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9 changes: 5 additions & 4 deletions lr35902.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1318,6 +1318,7 @@ void cpu_init() {

ext_cycles = 0;
int_count = 0;
halted = 0;
}

uint8_t disas_op(uint16_t off) {
Expand Down Expand Up @@ -1390,6 +1391,7 @@ int handle_interrupts() {
regs.ime_flag = 0;
return 20;
} else if (ienable & iflags & MASK_IO_INT_LCDSTAT_Int) {
//printf("LCDSTAT interrupt\n");
op_push(&regs.PC, NULL);
regs.PC = ADDR_INT_LCDSTAT_Int;
mem_bit_unset(IO_IFLAGS, MASK_IO_INT_LCDSTAT_Int);
Expand Down Expand Up @@ -1435,17 +1437,16 @@ int cpu_step() {
}
}

if ((int_cycles = handle_interrupts())) {
return int_cycles;
}

if (halted) {
if (mem_read_8(IO_IENABLE) & mem_read_8(IO_IFLAGS)) {
halted = 0;
} else {
return 4;
}
}
if ((int_cycles = handle_interrupts())) {
return int_cycles;
}

op = mem_read_8(regs.PC);

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2 changes: 2 additions & 0 deletions memory.c
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Original file line number Diff line number Diff line change
Expand Up @@ -144,6 +144,7 @@ uint8_t mem_read_io_8(uint16_t addr) {
case IO_SCROLLX:
case IO_WNDPOSY:
case IO_WNDPOSX:
case IO_LCDSTAT:
return screen_read_8(addr);
break;
case IO_JOYPAD:
Expand Down Expand Up @@ -199,6 +200,7 @@ void mem_write_io_8(uint16_t addr, uint8_t v) {
case IO_SCROLLX:
case IO_WNDPOSY:
case IO_WNDPOSX:
case IO_LCDSTAT:
screen_write_8(addr, v);
break;
case IO_JOYPAD:
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14 changes: 12 additions & 2 deletions rom.c
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Original file line number Diff line number Diff line change
Expand Up @@ -19,7 +19,7 @@ static uint8_t rom_ram_mode;

void rom_init() {
rom = NULL;
rom = NULL;
ram = NULL;
rom_info.title[0] = 0x00;
rom_bank = 0x01;
ram_bank = 0x00;
Expand Down Expand Up @@ -274,8 +274,12 @@ void mbc1_write_8(uint16_t addr, uint8_t v) {
}
}
if (addr >= 0xA000 && addr < 0xC000) {
ram[addr - 0xA000 + 0x2000 * ram_bank] = v;
if (ram_enable) {
//printf("Writing ram on bank %d\n", ram_bank);
ram[addr - 0xA000 + 0x2000 * ram_bank] = v;
}
}

}

uint8_t rom_read_8(uint16_t addr) {
Expand All @@ -287,10 +291,13 @@ uint8_t rom_read_8(uint16_t addr) {
return mbc1_read_8(addr);
break;
case MBC_2:
printf("MBC2 not supported yet\n");
break;
case MBC_3:
printf("MBC3 not supported yet\n");
break;
case MBC_5:
printf("MBC5 not supported yet\n");
break;
}
return 0;
Expand All @@ -304,10 +311,13 @@ void rom_write_8(uint16_t addr, uint8_t v){
mbc1_write_8(addr, v);
break;
case MBC_2:
printf("MBC2 not supported yet\n");
break;
case MBC_3:
printf("MBC3 not supported yet\n");
break;
case MBC_5:
printf("MBC5 not supported yet\n");
break;
}
}
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88 changes: 54 additions & 34 deletions screen.c
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Original file line number Diff line number Diff line change
Expand Up @@ -11,11 +11,12 @@ static uint8_t bg_disp[256 * 256];
static uint8_t win_disp[256 * 256];
static uint8_t obj_disp[256 * 256];

static int32_t t_oam, t_oam_vram, t_hblank, t_vblank;
static int t_oam, t_oam_vram, t_hblank, t_vblank;
static uint8_t cur_line, cmp_line;
static uint8_t reset;
static uint8_t bg_pal[4], obj0_pal[4], obj1_pal[4];
static uint8_t bgrdpal_reg, obj0pal_reg, obj1pal_reg;
static uint8_t lcdstat_reg;
static uint8_t scrollx_reg, scrolly_reg, wndposx_reg, wndposy_reg;

void set_pal(uint8_t *pal, uint8_t v) {
Expand Down Expand Up @@ -51,6 +52,7 @@ void screen_write_8(uint16_t addr, uint8_t v) {
scrolly_reg = v;
break;
case IO_SCROLLX:
//printf("Line %d, write scrollx: %d\n", cur_line, v);
scrollx_reg = v;
break;
case IO_WNDPOSY:
Expand All @@ -59,6 +61,8 @@ void screen_write_8(uint16_t addr, uint8_t v) {
case IO_WNDPOSX:
wndposx_reg = v;
break;
case IO_LCDSTAT:
lcdstat_reg = (lcdstat_reg & 0x07) | (v & 0xF8);
default:
break;
}
Expand Down Expand Up @@ -93,6 +97,8 @@ uint8_t screen_read_8(uint16_t addr) {
case IO_WNDPOSX:
return wndposx_reg;
break;
case IO_LCDSTAT:
return lcdstat_reg;
default:
break;
}
Expand Down Expand Up @@ -189,7 +195,7 @@ void screen_draw_line_bg(uint8_t line) {
switch (mem_bit_test(IO_LCDCONT,
MASK_IO_LCDCONT_BGWindow_Tile_Data_Select)) {
case OPT_BGWindow_Tile_Data_8800_97FF:
// Some work to do here !!!
// Some work to do here -> DONE
tile_data = 0x9000;
break;
case OPT_BGWindow_Tile_Data_8000_8FFF:
Expand All @@ -198,8 +204,8 @@ void screen_draw_line_bg(uint8_t line) {
}

// WIP WIP WIP
oam_row = (line + scrolly_reg) / 8;
obj_line = (line + scrolly_reg) % 8;
oam_row = (uint8_t)(line + scrolly_reg) / 8;
obj_line = (uint8_t)(line + scrolly_reg) % 8;
for (i = 0; i < 32; i++) {
if (tile_data == 0x9000) {
obj = (int8_t)mem_read_8(bg_tile_map + oam_row * 32 + i);
Expand All @@ -209,7 +215,7 @@ void screen_draw_line_bg(uint8_t line) {
obj_line_a = mem_read_8(tile_data + obj * 16 + obj_line * 2);
obj_line_b = mem_read_8(tile_data + obj * 16 + obj_line * 2 + 1);
for (j = 0; j < 8; j++) {
bg_disp[line * 256 + (i * 8 - scrollx_reg + j) % 256] =
bg_disp[line * 256 + (uint8_t)(i * 8 - scrollx_reg + j)] =
bg_pal[
((obj_line_a & (1 << (7 - j))) ? 1 : 0) +
((obj_line_b & (1 << (7 - j))) ? 2 : 0)
Expand Down Expand Up @@ -242,7 +248,7 @@ void screen_draw_line_win(uint8_t line) {
switch (mem_bit_test(IO_LCDCONT,
MASK_IO_LCDCONT_BGWindow_Tile_Data_Select)) {
case OPT_BGWindow_Tile_Data_8800_97FF:
// Some work to do here !!!
// Some work to do here -> DONE
tile_data = 0x9000;
break;
case OPT_BGWindow_Tile_Data_8000_8FFF:
Expand All @@ -251,9 +257,9 @@ void screen_draw_line_win(uint8_t line) {
}

// WIP WIP WIP
oam_row = (line - wndposy_reg) / 8;
obj_line = (line - wndposy_reg) % 8;
for (i = 0; i < (SCREEN_SIZE_X - wndposx_reg) / 8; i++) {
oam_row = (uint8_t)(line - wndposy_reg) / 8;
obj_line = (uint8_t)(line - wndposy_reg) % 8;
for (i = 0; i < (SCREEN_SIZE_X - (wndposx_reg - 8)) / 8; i++) {
if (tile_data == 0x9000) {
obj = (int8_t)mem_read_8(win_tile_map + oam_row * 32 + i);
} else {
Expand All @@ -262,7 +268,7 @@ void screen_draw_line_win(uint8_t line) {
obj_line_a = mem_read_8(tile_data + obj * 16 + obj_line * 2);
obj_line_b = mem_read_8(tile_data + obj * 16 + obj_line * 2 + 1);
for (j = 0; j < 8; j++) {
win_disp[line * 256 + (i * 8 + wndposx_reg + 7 + j) % 256] =
win_disp[line * 256 + (uint8_t)(i * 8 + wndposx_reg - 7 + j)] =
((obj_line_a & (1 << (7 - j))) ? 1 : 0) +
((obj_line_b & (1 << (7 - j))) ? 2 : 0);
}
Expand Down Expand Up @@ -367,7 +373,6 @@ void screen_draw_line_obj(uint8_t line) {
first = 0;
}

// Only taking into account 8x8!!!
for (i = first; i < objs_line_len; i++) {
x_flip = (objs_line[i]->flags & OPT_OBJ_Flag_xflip) ? 1 : 0;
y_flip = (objs_line[i]->flags & OPT_OBJ_Flag_yflip) ? 1 : 0;
Expand Down Expand Up @@ -412,6 +417,18 @@ void screen_draw_line(uint8_t line) {
screen_draw_line_fb(line);
}

void bit_set(uint8_t *v, uint8_t bit) {
*v |= bit;
}

void bit_unset(uint8_t *v, uint8_t bit) {
*v &= ~bit;
}

int bit_test(uint8_t v, uint8_t bit) {
return (v & bit) > 0;
}

int screen_emulate(uint32_t cycles) {
if (reset) {
reset = 0;
Expand All @@ -425,26 +442,25 @@ int screen_emulate(uint32_t cycles) {

// OAM mode 2
if (t_oam <= 0) {
cur_line = (cur_line + 1) % SCREEN_LINES;
//printf("line: %d\n", cur_line);
// update CURLINE REG
//mem_write_8(IO_CURLINE, cur_line);
if (cur_line == cmp_line) {
mem_bit_set(IO_LCDSTAT, MASK_IO_LCDSTAT_Coincidence_Flag);
if (mem_bit_test(IO_LCDSTAT,
bit_set(&lcdstat_reg, MASK_IO_LCDSTAT_Coincidence_Flag);
if (bit_test(lcdstat_reg,
MASK_IO_LCDSTAT_LYC_LY_Coincidence_Interrupt)) {
mem_bit_set(IO_IFLAGS, MASK_IO_INT_LCDSTAT_Int);
}
} else {
mem_bit_unset(IO_LCDSTAT, MASK_IO_LCDSTAT_Coincidence_Flag);
bit_unset(&lcdstat_reg, MASK_IO_LCDSTAT_Coincidence_Flag);
}

if (cur_line < SCREEN_SIZE_Y) {
lcdstat_reg = (lcdstat_reg & 0xF3) | 0x02;
// Set Mode Flag to OAM at LCDSTAT
mem_bit_unset(IO_LCDSTAT, MASK_IO_LCDSTAT_Mode_Flag);
mem_bit_set(IO_LCDSTAT, OPT_Mode_OAM);
bit_unset(&lcdstat_reg, MASK_IO_LCDSTAT_Mode_Flag);
bit_set(&lcdstat_reg, OPT_Mode_OAM);
// Interrupt OAM
if (mem_bit_test(IO_LCDSTAT,
if (bit_test(lcdstat_reg,
MASK_IO_LCDSTAT_Mode_2_OAM_Interrupt)) {
mem_bit_set(IO_IFLAGS, MASK_IO_INT_LCDSTAT_Int);
}
Expand All @@ -456,39 +472,43 @@ int screen_emulate(uint32_t cycles) {
// OAM VRAM mode 3
if (t_oam_vram <= 0) {
if (cur_line < SCREEN_SIZE_Y) {
lcdstat_reg = (lcdstat_reg & 0xF3) | 0x03;
// Set Mode Flag to OAM VRAM at LCDSTAT
mem_bit_unset(IO_LCDSTAT, MASK_IO_LCDSTAT_Mode_Flag);
mem_bit_set(IO_LCDSTAT, OPT_Mode_OAM_VRAM);
// draw line
screen_draw_line(cur_line);
bit_unset(&lcdstat_reg, MASK_IO_LCDSTAT_Mode_Flag);
bit_set(&lcdstat_reg, OPT_Mode_OAM_VRAM);
}
t_oam_vram += SCREEN_DUR_LINE;;
t_oam_vram += SCREEN_DUR_LINE;
}
// HBLANK mode 0
if (t_hblank <= 0) {
if (cur_line < SCREEN_SIZE_Y) {
lcdstat_reg = (lcdstat_reg & 0xF3) | 0x00;
// Set Mode Flag to HBLANK at LCDSTAT
mem_bit_unset(IO_LCDSTAT, MASK_IO_LCDSTAT_Mode_Flag);
mem_bit_set(IO_LCDSTAT, OPT_Mode_HBlank);
bit_unset(&lcdstat_reg, MASK_IO_LCDSTAT_Mode_Flag);
bit_set(&lcdstat_reg, OPT_Mode_HBlank);
// Interrupt HBlank
if (mem_bit_test(IO_LCDSTAT,
if (bit_test(lcdstat_reg,
MASK_IO_LCDSTAT_Mode_0_HBlank_Interrupt)) {
mem_bit_set(IO_IFLAGS, MASK_IO_INT_LCDSTAT_Int);
}
// draw line
screen_draw_line(cur_line);
}
t_hblank += SCREEN_DUR_LINE;;
cur_line = (cur_line + 1) % SCREEN_LINES;
t_hblank += SCREEN_DUR_LINE;
}
// VBLANK mode 1
if (t_vblank <= 0) {
lcdstat_reg = (lcdstat_reg & 0xF3) | 0x01;
// Set Mode Flag to VBLANK at LCDSTAT
mem_bit_unset(IO_LCDSTAT, MASK_IO_LCDSTAT_Mode_Flag);
mem_bit_set(IO_LCDSTAT, OPT_Mode_VBlank);
bit_unset(&lcdstat_reg, MASK_IO_LCDSTAT_Mode_Flag);
bit_set(&lcdstat_reg, OPT_Mode_VBlank);
// Interrupt VBlank
mem_bit_set(IO_IFLAGS, MASK_IO_INT_VBlank);
if (mem_bit_test(IO_LCDSTAT,
MASK_IO_LCDSTAT_Mode_1_VBlank_Interrupt)) {
mem_bit_set(IO_IFLAGS, MASK_IO_INT_LCDSTAT_Int);
}
if (bit_test(lcdstat_reg,
MASK_IO_LCDSTAT_Mode_1_VBlank_Interrupt)) {
mem_bit_set(IO_IFLAGS, MASK_IO_INT_LCDSTAT_Int);
}
t_vblank += SCREEN_DUR_FRAME;
}
return 0;
Expand Down
2 changes: 1 addition & 1 deletion screen.h
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Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@
#define SCREEN_DUR_OAM 80
#define SCREEN_DUR_OAM_VRAM 172
#define SCREEN_DUR_HBLANK 204
#define SCREEN_DUR_LINE 456
#define SCREEN_DUR_LINE 456 // 80 + 172 + 204
#define SCREEN_DUR_VBLANK 4560

// Start of each screen state in each line / frame
Expand Down

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