new packed cartridge format in preparation for, stuff

erisdev · Dec 23, 2016 · 80a4b5d · 80a4b5d
1 parent 21bf30d
commit 80a4b5d
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Showing 5 changed files with 123 additions and 56 deletions.
diff --git a/Makefile b/Makefile
@@ -10,8 +10,9 @@ LDFLAGS += -L$(Z80_DIR) -lz80 -g \
 .PHONY : all
 all : vg8m bios demo
 
-vg8m : sdl_driver.o vg8m.o video.o | libz80
+vg8m : sdl_driver.o vg8m.o cart.o video.o | libz80
 
+cart.o : cart.c vg8m.h
 vg8m.o : vg8m.c vg8m.h
 video.o : video.c video.h vg8m.h
 sdl_driver.o : sdl_driver.c vg8m.h video.h

diff --git a/cart.c b/cart.c
@@ -0,0 +1,65 @@
+#include "config.h"
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "vg8m.h"
+#include "internal.h"
+
+static const char MAGIC[] = "VGDMP100";
+
+typedef struct s_dump_header DumpHeader;
+struct s_dump_header {
+    char magic[8];
+    uint16_t flags;
+    uint16_t prog_offset;
+    uint16_t prog_size;
+    uint16_t pat_2bpp_offset;
+    uint16_t pat_2bpp_size;
+    uint16_t pat_3bpp_offset;
+    uint16_t pat_3bpp_size;
+};
+
+typedef struct s_cart_header CartHeader;
+struct s_cart_header {
+    char magic[8];
+    char title[0x20];
+    char developer[0x20];
+    char lang[2];
+    uint16_t flags;
+    uint8_t version;
+};
+
+bool vg8m_load_cart(VG8M *emu, const char *filename) {
+    DumpHeader header;
+    int fd = open(filename, O_RDONLY);
+    if (fd == -1) goto error;
+
+    if (read(fd, &header, sizeof(header)) == -1)
+        goto error;
+
+    if (header.prog_size > 0) {
+        if (lseek(fd, header.prog_offset, SEEK_SET) == -1
+        ||  read(fd, emu->cart_prog_rom, header.prog_size) == -1)
+            goto error;
+    }
+
+    if (header.pat_2bpp_size > 0) {
+        if (lseek(fd, header.pat_2bpp_offset, SEEK_SET) == -1
+        ||  read(fd, emu->cart_2bpp_rom, header.pat_2bpp_size) == -1)
+            goto error;
+    }
+
+    if (header.pat_3bpp_size > 0) {
+        if (lseek(fd, header.pat_3bpp_offset, SEEK_SET) == -1
+        ||  read(fd, emu->cart_3bpp_rom, header.pat_3bpp_size) == -1)
+            goto error;
+    }
+
+    close(fd);
+    return true;
+error:
+    if (fd != -1) close(fd);
+    return false;
+}
diff --git a/internal.h b/internal.h
@@ -0,0 +1,41 @@
+#pragma once
+#include "vg8m.h"
+
+enum {
+    SYS_ROM_SIZE  = 0x0800,
+    SYS_RAM_SIZE  = 0x0700,
+    HWREGS_SIZE   = sizeof(VG8MRegisters),
+    CHAR_ROM_SIZE = 0x1000,
+    USER_RAM_SIZE = 0x4000,
+    CART_ROM_SIZE = 0x8000,
+
+    CART_2BPP_SIZE = 0x4000,
+    CART_3BPP_SIZE = 0x3000,
+};
+
+
+enum {
+    SYS_ROM_ADDR  = 0x0000, SYS_ROM_END  = 0x07FF,
+    SYS_RAM_ADDR  = 0x0800, SYS_RAM_END  = 0x0EFF,
+    HWREGS_ADDR   = 0x0F00, HWREGS_END   = HWREGS_ADDR + HWREGS_SIZE - 1,
+    CHAR_ROM_ADDR = 0x1000, CHAR_ROM_END = 0x1FFF,
+    USER_RAM_ADDR = 0x4000, USER_RAM_END = 0x7FFF,
+    CART_ROM_ADDR = 0x8000, CART_ROM_END = 0xFFFF,
+};
+
+enum {
+    INT_VBLANK = 0x20,
+    INT_HBLANK = 0x22,
+};
+
+enum {
+    MODE_HBLANK,
+    MODE_VBLANK,
+    MODE_DRAW,
+};
+
+enum {
+    CYCLES_HBLANK = 200,
+    CYCLES_VBLANK = 500,
+    CYCLES_DRAW   = 200,
+};
diff --git a/vg8m.c b/vg8m.c
@@ -13,6 +13,7 @@
 
 #include "vg8m.h"
 #include "video.h"
+#include "internal.h"
 
 static uint8_t *_load_file(uint16_t size, const char *filename);
 static void _unload_file(uint8_t *buffer, uint16_t size);
@@ -23,49 +24,16 @@ static void _writeio(VG8M *emu, uint16_t addr, uint8_t data);
 static uint8_t _readmem(VG8M *emu, uint16_t addr);
 static void _writemem(VG8M *emu, uint16_t addr, uint8_t data);
 
-enum {
-    SYS_ROM_SIZE  = 0x0800,
-    SYS_RAM_SIZE  = 0x0700,
-    HWREGS_SIZE   = sizeof(VG8MRegisters),
-    CHAR_ROM_SIZE = 0x1000,
-    USER_RAM_SIZE = 0x4000,
-    CART_ROM_SIZE = 0x8000,
-};
-
-
-enum {
-    SYS_ROM_ADDR  = 0x0000, SYS_ROM_END  = 0x07FF,
-    SYS_RAM_ADDR  = 0x0800, SYS_RAM_END  = 0x0EFF,
-    HWREGS_ADDR   = 0x0F00, HWREGS_END   = HWREGS_ADDR + HWREGS_SIZE - 1,
-    CHAR_ROM_ADDR = 0x1000, CHAR_ROM_END = 0x1FFF,
-    USER_RAM_ADDR = 0x4000, USER_RAM_END = 0x7FFF,
-    CART_ROM_ADDR = 0x8000, CART_ROM_END = 0xFFFF,
-};
-
-enum {
-    INT_VBLANK = 0x20,
-    INT_HBLANK = 0x22,
-};
-
-enum {
-    MODE_HBLANK,
-    MODE_VBLANK,
-    MODE_DRAW,
-};
-
-enum {
-    CYCLES_HBLANK = 200,
-    CYCLES_VBLANK = 500,
-    CYCLES_DRAW   = 200,
-};
-
 static inline uint16_t _min(uint16_t a, uint16_t b) {
     return a < b ? a : b;
 }
 
 void vg8m_init(VG8M *emu) {
     emu->system_ram     = calloc(SYS_RAM_SIZE, sizeof(uint8_t));
     emu->user_ram       = calloc(USER_RAM_SIZE, sizeof(uint8_t));
+    emu->cart_prog_rom  = calloc(CART_ROM_SIZE, sizeof(uint8_t));
+    emu->cart_2bpp_rom  = calloc(CART_2BPP_SIZE, sizeof(uint8_t));
+    emu->cart_3bpp_rom  = calloc(CART_3BPP_SIZE, sizeof(uint8_t));
 
     // memcpy(emu->system_rom,     bios_system_bin,   bios_system_bin_len);
     // memcpy(emu->system_charset, bios_charset_1bpp, bios_charset_1bpp_len);
@@ -90,11 +58,13 @@ void vg8m_fin(VG8M *emu) {
     // free(emu->system_rom);
     free(emu->system_ram);
     free(emu->user_ram);
+    free(emu->cart_prog_rom);
+    free(emu->cart_2bpp_rom);
+    free(emu->cart_3bpp_rom);
     free(emu->cpu);
 
     _unload_file(emu->system_rom, SYS_ROM_SIZE);
     _unload_file(emu->system_charset, CHAR_ROM_SIZE);
-    _unload_file(emu->cartridge_rom, CART_ROM_SIZE);
 }
 
 void vg8m_reset(VG8M *emu) {
@@ -153,21 +123,6 @@ bool vg8m_load_system(VG8M *emu, const char *rom_filename, const char *charset_f
     return false;
 }
 
-bool vg8m_load_cart(VG8M *emu, const char *filename) {
-    uint8_t *buffer = NULL;
-
-    buffer = _load_file(CART_ROM_SIZE, filename);
-    if (!buffer)
-        goto error;
-
-    emu->cartridge_rom = buffer;
-
-    return true;
-error:
-    _unload_file(buffer, CART_ROM_SIZE);
-    return false;
-}
-
 void vg8m_set_buttons(VG8M *emu, VG8MButtonMask buttons, bool pressed) {
     if (pressed)
         emu->hwregs.buttons |= buttons;
@@ -323,8 +278,8 @@ static uint8_t _readmem(VG8M *emu, uint16_t addr) {
     else if (inregion(addr, USER_RAM_ADDR, USER_RAM_END))
         return emu->user_ram[addr - USER_RAM_ADDR];
 
-    else if (inregion(addr, CART_ROM_ADDR, CART_ROM_END) && emu->cartridge_rom)
-        return emu->cartridge_rom[addr - CART_ROM_ADDR];
+    else if (inregion(addr, CART_ROM_ADDR, CART_ROM_END))
+        return emu->cart_prog_rom[addr - CART_ROM_ADDR];
 
     return 0xFF;
 }

diff --git a/vg8m.h b/vg8m.h
@@ -1,4 +1,7 @@
 #pragma once
+#include <stdbool.h>
+#include <stdint.h>
+
 #include "z80.h"
 
 typedef struct s_vg8m VG8M;
@@ -36,7 +39,9 @@ struct s_vg8m {
     uint8_t *system_ram;
     uint8_t *system_charset;
     uint8_t *user_ram;
-    uint8_t *cartridge_rom;
+    uint8_t *cart_prog_rom;
+    uint8_t *cart_2bpp_rom;
+    uint8_t *cart_3bpp_rom;
     VG8MRegisters hwregs;
 
     VG8MCallback scanline_callback;