beginning ppu

include/common.h

@@ -15,5 +15,6 @@ typedef uint64_t u64;
 #define BETWEEN(a, b, c) ((a >= b) && (a <= c))
 
 void delay(u32 ms);
+u32 get_ticks();
 
 #define NO_IMPL { fprintf(stderr, "NOT YET IMPLEMENTED\n"); exit(-5); }

include/dma.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <common.h>
+
+void dma_start(u8 start);
+void dma_tick();
+
+bool dma_transferring();

include/lcd.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include <common.h>
+
+typedef struct {
+    //registers
+    u8 lcdc;
+    u8 lcds;
+    u8 scroll_y;
+    u8 scroll_x;
+    u8 ly;
+    u8 ly_compare;
+    u8 dma;
+    u8 bg_palette;
+    u8 obj_palette[2];
+    u8 win_y;
+    u8 win_x;
+
+    //other data...
+    u32 bg_colors[4];
+    u32 sp1_colors[4];
+    u32 sp2_colors[4];
+} lcd_context;
+
+typedef enum {
+    MODE_HBLANK,
+    MODE_VBLANK,
+    MODE_OAM,
+    MODE_XFER
+} lcd_mode;
+
+lcd_context *lcd_get_context();
+
+#define LCDC_BGW_ENABLE (BIT(lcd_get_context()->lcdc, 0))
+#define LCDC_OBJ_ENABLE (BIT(lcd_get_context()->lcdc, 1))
+#define LCDC_OBJ_HEIGHT (BIT(lcd_get_context()->lcdc, 2) ? 16 : 8)
+#define LCDC_BG_MAP_AREA (BIT(lcd_get_context()->lcdc, 3) ? 0x9C00 : 0x9800)
+#define LCDC_BGW_DATA_AREA (BIT(lcd_get_context()->lcdc, 4) ? 0x8000 : 0x8800)
+#define LCDC_WIN_ENABLE (BIT(lcd_get_context()->lcdc, 5))
+#define LCDC_WIN_MAP_AREA (BIT(lcd_get_context()->lcdc, 6) ? 0x9C00 : 0x9800)
+#define LCDC_LCD_ENABLE (BIT(lcd_get_context()->lcdc, 7))
+
+#define LCDS_MODE ((lcd_mode)(lcd_get_context()->lcds & 0b11))
+#define LCDS_MODE_SET(mode) { lcd_get_context()->lcds &= ~0b11; lcd_get_context()->lcdc |= mode; }
+#define LCDS_LYC (BIT(lcd_get_context()->lcds, 2))
+#define LCDS_LYC_SET(b) BIT_SET(lcd_get_context()->lcds, 2, b)
+
+typedef enum {
+    SS_HBLANK = (1 << 3),
+    SS_VBLANK = (1 << 4),
+    SS_OAM = (1 << 5),
+    SS_LYC = (1 << 6)
+} stat_src;
+
+#define LCDS_STAT_INT(src) (lcd_get_context()->lcds & src)
+
+void lcd_init();
+
+u8 lcd_read(u16 address);
+void lcd_write(u16 address, u8 value);

include/ppu.h

@@ -2,5 +2,40 @@
 
 #include <common.h>
 
+static const LINES_PER_FRAME = 154;
+static const TICKS_PER_LINE = 456;
+static const YRES = 144;
+static const XRES = 160;
+
+typedef struct {
+    u8 y;
+    u8 x;
+    u8 tile;
+
+    unsigned f_cgb_pn : 3;
+    unsigned f_cgb_vram_bank : 1;
+    unsigned f_pn : 1;
+    unsigned f_x_flip : 1;
+    unsigned f_y_flip : 1;
+    unsigned f_bgp : 1;
+} oam_entry;
+
+typedef struct {
+    oam_entry oam_ram[40];
+    u8 vram[0x2000];
+
+    u32 current_frame;
+    u32 line_ticks;
+    u32 *video_buffer;
+} ppu_context;
+
 void ppu_init();
-void ppu_tick();
+void ppu_tick();
+
+void ppu_oam_write(u16 address, u8 value);
+u8 ppu_oam_read(u16 address);
+
+void ppu_vram_write(u16 address, u8 value);
+u8 ppu_vram_read(u16 address);
+
+ppu_context *ppu_get_context();

include/ppu_sm.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <common.h>
+
+void ppu_mode_oam();
+void ppu_mode_xfer();
+void ppu_mode_vblank();
+void ppu_mode_hblank();

include/timer.h

@@ -2,5 +2,17 @@
 
 #include <common.h>
 
+typedef struct {
+    u16 div;
+    u8 tima;
+    u8 tma;
+    u8 tac;
+} timer_context;
+
 void timer_init();
-void timer_tick();
+void timer_tick();
+
+void timer_write(u16 address, u8 value);
+u8 timer_read(u16 address);
+
+timer_context *timer_get_context();

include/ui.h

@@ -6,4 +6,5 @@ static const int SCREEN_WIDTH = 1024;
 static const int SCREEN_HEIGHT = 768;
 
 void ui_init();
-void ui_handle_events();
+void ui_handle_events();
+void ui_update();