Genesis-Plus-GX/sdl/sdl1/main.c

942 lines
24 KiB
C

#ifdef __WIN32__
#include <windows.h>
#else
#define MessageBox(owner, text, caption, type) printf("%s: %s\n", caption, text)
#endif
#include "SDL.h"
#include "SDL_thread.h"
#include "shared.h"
#include "sms_ntsc.h"
#include "md_ntsc.h"
#define SOUND_FREQUENCY 48000
#define SOUND_SAMPLES_SIZE 2048
#define VIDEO_WIDTH 320
#define VIDEO_HEIGHT 240
int joynum = 0;
int log_error = 0;
int debug_on = 0;
int turbo_mode = 0;
int use_sound = 1;
int fullscreen = 0; /* SDL_FULLSCREEN */
/* sound */
struct {
char* current_pos;
char* buffer;
int current_emulated_samples;
} sdl_sound;
static uint8 brm_format[0x40] =
{
0x5f,0x5f,0x5f,0x5f,0x5f,0x5f,0x5f,0x5f,0x5f,0x5f,0x5f,0x00,0x00,0x00,0x00,0x40,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x53,0x45,0x47,0x41,0x5f,0x43,0x44,0x5f,0x52,0x4f,0x4d,0x00,0x01,0x00,0x00,0x00,
0x52,0x41,0x4d,0x5f,0x43,0x41,0x52,0x54,0x52,0x49,0x44,0x47,0x45,0x5f,0x5f,0x5f
};
static short soundframe[SOUND_SAMPLES_SIZE];
static void sdl_sound_callback(void *userdata, Uint8 *stream, int len)
{
if(sdl_sound.current_emulated_samples < len) {
memset(stream, 0, len);
}
else {
memcpy(stream, sdl_sound.buffer, len);
/* loop to compensate desync */
do {
sdl_sound.current_emulated_samples -= len;
} while(sdl_sound.current_emulated_samples > 2 * len);
memcpy(sdl_sound.buffer,
sdl_sound.current_pos - sdl_sound.current_emulated_samples,
sdl_sound.current_emulated_samples);
sdl_sound.current_pos = sdl_sound.buffer + sdl_sound.current_emulated_samples;
}
}
static int sdl_sound_init()
{
int n;
SDL_AudioSpec as_desired;
if(SDL_Init(SDL_INIT_AUDIO) < 0) {
MessageBox(NULL, "SDL Audio initialization failed", "Error", 0);
return 0;
}
as_desired.freq = SOUND_FREQUENCY;
as_desired.format = AUDIO_S16SYS;
as_desired.channels = 2;
as_desired.samples = SOUND_SAMPLES_SIZE;
as_desired.callback = sdl_sound_callback;
if(SDL_OpenAudio(&as_desired, NULL) == -1) {
MessageBox(NULL, "SDL Audio open failed", "Error", 0);
return 0;
}
sdl_sound.current_emulated_samples = 0;
n = SOUND_SAMPLES_SIZE * 2 * sizeof(short) * 20;
sdl_sound.buffer = (char*)malloc(n);
if(!sdl_sound.buffer) {
MessageBox(NULL, "Can't allocate audio buffer", "Error", 0);
return 0;
}
memset(sdl_sound.buffer, 0, n);
sdl_sound.current_pos = sdl_sound.buffer;
return 1;
}
static void sdl_sound_update(int enabled)
{
int size = audio_update(soundframe) * 2;
if (enabled)
{
int i;
short *out;
SDL_LockAudio();
out = (short*)sdl_sound.current_pos;
for(i = 0; i < size; i++)
{
*out++ = soundframe[i];
}
sdl_sound.current_pos = (char*)out;
sdl_sound.current_emulated_samples += size * sizeof(short);
SDL_UnlockAudio();
}
}
static void sdl_sound_close()
{
SDL_PauseAudio(1);
SDL_CloseAudio();
if (sdl_sound.buffer)
free(sdl_sound.buffer);
}
/* video */
md_ntsc_t *md_ntsc;
sms_ntsc_t *sms_ntsc;
struct {
SDL_Surface* surf_screen;
SDL_Surface* surf_bitmap;
SDL_Rect srect;
SDL_Rect drect;
Uint32 frames_rendered;
} sdl_video;
static int sdl_video_init()
{
if(SDL_InitSubSystem(SDL_INIT_VIDEO) < 0) {
MessageBox(NULL, "SDL Video initialization failed", "Error", 0);
return 0;
}
sdl_video.surf_screen = SDL_SetVideoMode(VIDEO_WIDTH, VIDEO_HEIGHT, 16, SDL_SWSURFACE | fullscreen);
sdl_video.surf_bitmap = SDL_CreateRGBSurface(SDL_SWSURFACE, 720, 576, 16, 0, 0, 0, 0);
sdl_video.frames_rendered = 0;
SDL_ShowCursor(0);
return 1;
}
static void sdl_video_update()
{
if (system_hw == SYSTEM_MCD)
{
system_frame_scd(0);
}
else if ((system_hw & SYSTEM_PBC) == SYSTEM_MD)
{
system_frame_gen(0);
}
else
{
system_frame_sms(0);
}
/* viewport size changed */
if(bitmap.viewport.changed & 1)
{
bitmap.viewport.changed &= ~1;
/* source bitmap */
sdl_video.srect.w = bitmap.viewport.w+2*bitmap.viewport.x;
sdl_video.srect.h = bitmap.viewport.h+2*bitmap.viewport.y;
sdl_video.srect.x = 0;
sdl_video.srect.y = 0;
if (sdl_video.srect.w > VIDEO_WIDTH)
{
sdl_video.srect.x = (sdl_video.srect.w - VIDEO_WIDTH) / 2;
sdl_video.srect.w = VIDEO_WIDTH;
}
if (sdl_video.srect.h > VIDEO_HEIGHT)
{
sdl_video.srect.y = (sdl_video.srect.h - VIDEO_HEIGHT) / 2;
sdl_video.srect.h = VIDEO_HEIGHT;
}
/* destination bitmap */
sdl_video.drect.w = sdl_video.srect.w;
sdl_video.drect.h = sdl_video.srect.h;
sdl_video.drect.x = (VIDEO_WIDTH - sdl_video.drect.w) / 2;
sdl_video.drect.y = (VIDEO_HEIGHT - sdl_video.drect.h) / 2;
/* clear destination surface */
SDL_FillRect(sdl_video.surf_screen, 0, 0);
#if 0
if (config.render && (interlaced || config.ntsc)) rect.h *= 2;
if (config.ntsc) rect.w = (reg[12]&1) ? MD_NTSC_OUT_WIDTH(rect.w) : SMS_NTSC_OUT_WIDTH(rect.w);
if (config.ntsc)
{
sms_ntsc = (sms_ntsc_t *)malloc(sizeof(sms_ntsc_t));
md_ntsc = (md_ntsc_t *)malloc(sizeof(md_ntsc_t));
switch (config.ntsc)
{
case 1:
sms_ntsc_init(sms_ntsc, &sms_ntsc_composite);
md_ntsc_init(md_ntsc, &md_ntsc_composite);
break;
case 2:
sms_ntsc_init(sms_ntsc, &sms_ntsc_svideo);
md_ntsc_init(md_ntsc, &md_ntsc_svideo);
break;
case 3:
sms_ntsc_init(sms_ntsc, &sms_ntsc_rgb);
md_ntsc_init(md_ntsc, &md_ntsc_rgb);
break;
}
}
else
{
if (sms_ntsc)
{
free(sms_ntsc);
sms_ntsc = NULL;
}
if (md_ntsc)
{
free(md_ntsc);
md_ntsc = NULL;
}
}
#endif
}
SDL_BlitSurface(sdl_video.surf_bitmap, &sdl_video.srect, sdl_video.surf_screen, &sdl_video.drect);
SDL_UpdateRect(sdl_video.surf_screen, 0, 0, 0, 0);
++sdl_video.frames_rendered;
}
static void sdl_video_close()
{
SDL_FreeSurface(sdl_video.surf_bitmap);
}
/* Timer Sync */
struct {
SDL_sem* sem_sync;
unsigned ticks;
} sdl_sync;
static Uint32 sdl_sync_timer_callback(Uint32 interval)
{
SDL_SemPost(sdl_sync.sem_sync);
sdl_sync.ticks++;
if (sdl_sync.ticks == (vdp_pal ? 50 : 20))
{
SDL_Event event;
SDL_UserEvent userevent;
userevent.type = SDL_USEREVENT;
userevent.code = vdp_pal ? (sdl_video.frames_rendered / 3) : sdl_video.frames_rendered;
userevent.data1 = NULL;
userevent.data2 = NULL;
sdl_sync.ticks = sdl_video.frames_rendered = 0;
event.type = SDL_USEREVENT;
event.user = userevent;
SDL_PushEvent(&event);
}
return interval;
}
static int sdl_sync_init()
{
if(SDL_InitSubSystem(SDL_INIT_TIMER|SDL_INIT_EVENTTHREAD) < 0)
{
MessageBox(NULL, "SDL Timer initialization failed", "Error", 0);
return 0;
}
sdl_sync.sem_sync = SDL_CreateSemaphore(0);
sdl_sync.ticks = 0;
return 1;
}
static void sdl_sync_close()
{
if(sdl_sync.sem_sync)
SDL_DestroySemaphore(sdl_sync.sem_sync);
}
static const uint16 vc_table[4][2] =
{
/* NTSC, PAL */
{0xDA , 0xF2}, /* Mode 4 (192 lines) */
{0xEA , 0x102}, /* Mode 5 (224 lines) */
{0xDA , 0xF2}, /* Mode 4 (192 lines) */
{0x106, 0x10A} /* Mode 5 (240 lines) */
};
static int sdl_control_update(SDLKey keystate)
{
switch (keystate)
{
case SDLK_TAB:
{
system_reset();
break;
}
case SDLK_F1:
{
if (SDL_ShowCursor(-1)) SDL_ShowCursor(0);
else SDL_ShowCursor(1);
break;
}
case SDLK_F2:
{
fullscreen = (fullscreen ? 0 : SDL_FULLSCREEN);
sdl_video.surf_screen = SDL_SetVideoMode(VIDEO_WIDTH, VIDEO_HEIGHT, 16, SDL_SWSURFACE | fullscreen);
break;
}
case SDLK_F3:
{
if (config.bios == 0) config.bios = 3;
else if (config.bios == 3) config.bios = 1;
break;
}
case SDLK_F4:
{
if (!turbo_mode) use_sound ^= 1;
break;
}
case SDLK_F5:
{
log_error ^= 1;
break;
}
case SDLK_F6:
{
if (!use_sound)
{
turbo_mode ^=1;
sdl_sync.ticks = 0;
}
break;
}
case SDLK_F7:
{
FILE *f = fopen("game.gp0","rb");
if (f)
{
uint8 buf[STATE_SIZE];
fread(&buf, STATE_SIZE, 1, f);
state_load(buf);
fclose(f);
}
break;
}
case SDLK_F8:
{
FILE *f = fopen("game.gp0","wb");
if (f)
{
uint8 buf[STATE_SIZE];
int len = state_save(buf);
fwrite(&buf, len, 1, f);
fclose(f);
}
break;
}
case SDLK_F9:
{
config.region_detect = (config.region_detect + 1) % 5;
get_region(0);
/* framerate has changed, reinitialize audio timings */
audio_init(snd.sample_rate, 0);
/* system with region BIOS should be reinitialized */
if ((system_hw == SYSTEM_MCD) || ((system_hw & SYSTEM_SMS) && (config.bios & 1)))
{
system_init();
system_reset();
}
else
{
/* reinitialize I/O region register */
if (system_hw == SYSTEM_MD)
{
io_reg[0x00] = 0x20 | region_code | (config.bios & 1);
}
else
{
io_reg[0x00] = 0x80 | (region_code >> 1);
}
/* reinitialize VDP */
if (vdp_pal)
{
status |= 1;
lines_per_frame = 313;
}
else
{
status &= ~1;
lines_per_frame = 262;
}
/* reinitialize VC max value */
switch (bitmap.viewport.h)
{
case 192:
vc_max = vc_table[0][vdp_pal];
break;
case 224:
vc_max = vc_table[1][vdp_pal];
break;
case 240:
vc_max = vc_table[3][vdp_pal];
break;
}
}
break;
}
case SDLK_F10:
{
gen_reset(0);
break;
}
case SDLK_F11:
{
config.overscan = (config.overscan + 1) & 3;
if ((system_hw == SYSTEM_GG) && !config.gg_extra)
{
bitmap.viewport.x = (config.overscan & 2) ? 14 : -48;
}
else
{
bitmap.viewport.x = (config.overscan & 2) * 7;
}
bitmap.viewport.changed = 3;
break;
}
case SDLK_F12:
{
joynum = (joynum + 1) % MAX_DEVICES;
while (input.dev[joynum] == NO_DEVICE)
{
joynum = (joynum + 1) % MAX_DEVICES;
}
break;
}
case SDLK_ESCAPE:
{
return 0;
}
default:
break;
}
return 1;
}
int sdl_input_update(void)
{
uint8 *keystate = SDL_GetKeyState(NULL);
/* reset input */
input.pad[joynum] = 0;
switch (input.dev[joynum])
{
case DEVICE_LIGHTGUN:
{
/* get mouse coordinates (absolute values) */
int x,y;
int state = SDL_GetMouseState(&x,&y);
/* X axis */
input.analog[joynum][0] = x - (VIDEO_WIDTH-bitmap.viewport.w)/2;
/* Y axis */
input.analog[joynum][1] = y - (VIDEO_HEIGHT-bitmap.viewport.h)/2;
/* TRIGGER, B, C (Menacer only), START (Menacer & Justifier only) */
if(state & SDL_BUTTON_LMASK) input.pad[joynum] |= INPUT_A;
if(state & SDL_BUTTON_RMASK) input.pad[joynum] |= INPUT_B;
if(state & SDL_BUTTON_MMASK) input.pad[joynum] |= INPUT_C;
if(keystate[SDLK_f]) input.pad[joynum] |= INPUT_START;
break;
}
case DEVICE_PADDLE:
{
/* get mouse (absolute values) */
int x;
int state = SDL_GetMouseState(&x, NULL);
/* Range is [0;256], 128 being middle position */
input.analog[joynum][0] = x * 256 /VIDEO_WIDTH;
/* Button I -> 0 0 0 0 0 0 0 I*/
if(state & SDL_BUTTON_LMASK) input.pad[joynum] |= INPUT_B;
break;
}
case DEVICE_SPORTSPAD:
{
/* get mouse (relative values) */
int x,y;
int state = SDL_GetRelativeMouseState(&x,&y);
/* Range is [0;256] */
input.analog[joynum][0] = (unsigned char)(-x & 0xFF);
input.analog[joynum][1] = (unsigned char)(-y & 0xFF);
/* Buttons I & II -> 0 0 0 0 0 0 II I*/
if(state & SDL_BUTTON_LMASK) input.pad[joynum] |= INPUT_B;
if(state & SDL_BUTTON_RMASK) input.pad[joynum] |= INPUT_C;
break;
}
case DEVICE_MOUSE:
{
/* get mouse (relative values) */
int x,y;
int state = SDL_GetRelativeMouseState(&x,&y);
/* Sega Mouse range is [-256;+256] */
input.analog[joynum][0] = x * 2;
input.analog[joynum][1] = y * 2;
/* Vertical movement is upsidedown */
if (!config.invert_mouse)
input.analog[joynum][1] = 0 - input.analog[joynum][1];
/* Start,Left,Right,Middle buttons -> 0 0 0 0 START MIDDLE RIGHT LEFT */
if(state & SDL_BUTTON_LMASK) input.pad[joynum] |= INPUT_B;
if(state & SDL_BUTTON_RMASK) input.pad[joynum] |= INPUT_C;
if(state & SDL_BUTTON_MMASK) input.pad[joynum] |= INPUT_A;
if(keystate[SDLK_f]) input.pad[joynum] |= INPUT_START;
break;
}
case DEVICE_XE_1AP:
{
/* A,B,C,D,Select,START,E1,E2 buttons -> E1(?) E2(?) START SELECT(?) A B C D */
if(keystate[SDLK_a]) input.pad[joynum] |= INPUT_START;
if(keystate[SDLK_s]) input.pad[joynum] |= INPUT_A;
if(keystate[SDLK_d]) input.pad[joynum] |= INPUT_C;
if(keystate[SDLK_f]) input.pad[joynum] |= INPUT_Y;
if(keystate[SDLK_z]) input.pad[joynum] |= INPUT_B;
if(keystate[SDLK_x]) input.pad[joynum] |= INPUT_X;
if(keystate[SDLK_c]) input.pad[joynum] |= INPUT_MODE;
if(keystate[SDLK_v]) input.pad[joynum] |= INPUT_Z;
/* Left Analog Stick (bidirectional) */
if(keystate[SDLK_UP]) input.analog[joynum][1]-=2;
else if(keystate[SDLK_DOWN]) input.analog[joynum][1]+=2;
else input.analog[joynum][1] = 128;
if(keystate[SDLK_LEFT]) input.analog[joynum][0]-=2;
else if(keystate[SDLK_RIGHT]) input.analog[joynum][0]+=2;
else input.analog[joynum][0] = 128;
/* Right Analog Stick (unidirectional) */
if(keystate[SDLK_KP8]) input.analog[joynum+1][0]-=2;
else if(keystate[SDLK_KP2]) input.analog[joynum+1][0]+=2;
else if(keystate[SDLK_KP4]) input.analog[joynum+1][0]-=2;
else if(keystate[SDLK_KP6]) input.analog[joynum+1][0]+=2;
else input.analog[joynum+1][0] = 128;
/* Limiters */
if (input.analog[joynum][0] > 0xFF) input.analog[joynum][0] = 0xFF;
else if (input.analog[joynum][0] < 0) input.analog[joynum][0] = 0;
if (input.analog[joynum][1] > 0xFF) input.analog[joynum][1] = 0xFF;
else if (input.analog[joynum][1] < 0) input.analog[joynum][1] = 0;
if (input.analog[joynum+1][0] > 0xFF) input.analog[joynum+1][0] = 0xFF;
else if (input.analog[joynum+1][0] < 0) input.analog[joynum+1][0] = 0;
if (input.analog[joynum+1][1] > 0xFF) input.analog[joynum+1][1] = 0xFF;
else if (input.analog[joynum+1][1] < 0) input.analog[joynum+1][1] = 0;
break;
}
case DEVICE_PICO:
{
/* get mouse (absolute values) */
int x,y;
int state = SDL_GetMouseState(&x,&y);
/* Calculate X Y axis values */
input.analog[0][0] = 0x3c + (x * (0x17c-0x03c+1)) / VIDEO_WIDTH;
input.analog[0][1] = 0x1fc + (y * (0x2f7-0x1fc+1)) / VIDEO_HEIGHT;
/* Map mouse buttons to player #1 inputs */
if(state & SDL_BUTTON_MMASK) pico_current = (pico_current + 1) & 7;
if(state & SDL_BUTTON_RMASK) input.pad[0] |= INPUT_PICO_RED;
if(state & SDL_BUTTON_LMASK) input.pad[0] |= INPUT_PICO_PEN;
break;
}
case DEVICE_TEREBI:
{
/* get mouse (absolute values) */
int x,y;
int state = SDL_GetMouseState(&x,&y);
/* Calculate X Y axis values */
input.analog[0][0] = (x * 250) / VIDEO_WIDTH;
input.analog[0][1] = (y * 250) / VIDEO_HEIGHT;
/* Map mouse buttons to player #1 inputs */
if(state & SDL_BUTTON_RMASK) input.pad[0] |= INPUT_B;
break;
}
case DEVICE_GRAPHIC_BOARD:
{
/* get mouse (absolute values) */
int x,y;
int state = SDL_GetMouseState(&x,&y);
/* Calculate X Y axis values */
input.analog[0][0] = (x * 255) / VIDEO_WIDTH;
input.analog[0][1] = (y * 255) / VIDEO_HEIGHT;
/* Map mouse buttons to player #1 inputs */
if(state & SDL_BUTTON_LMASK) input.pad[0] |= INPUT_GRAPHIC_PEN;
if(state & SDL_BUTTON_RMASK) input.pad[0] |= INPUT_GRAPHIC_MENU;
if(state & SDL_BUTTON_MMASK) input.pad[0] |= INPUT_GRAPHIC_DO;
break;
}
case DEVICE_ACTIVATOR:
{
if(keystate[SDLK_g]) input.pad[joynum] |= INPUT_ACTIVATOR_7L;
if(keystate[SDLK_h]) input.pad[joynum] |= INPUT_ACTIVATOR_7U;
if(keystate[SDLK_j]) input.pad[joynum] |= INPUT_ACTIVATOR_8L;
if(keystate[SDLK_k]) input.pad[joynum] |= INPUT_ACTIVATOR_8U;
}
default:
{
if(keystate[SDLK_a]) input.pad[joynum] |= INPUT_A;
if(keystate[SDLK_s]) input.pad[joynum] |= INPUT_B;
if(keystate[SDLK_d]) input.pad[joynum] |= INPUT_C;
if(keystate[SDLK_f]) input.pad[joynum] |= INPUT_START;
if(keystate[SDLK_z]) input.pad[joynum] |= INPUT_X;
if(keystate[SDLK_x]) input.pad[joynum] |= INPUT_Y;
if(keystate[SDLK_c]) input.pad[joynum] |= INPUT_Z;
if(keystate[SDLK_v]) input.pad[joynum] |= INPUT_MODE;
if(keystate[SDLK_UP]) input.pad[joynum] |= INPUT_UP;
else
if(keystate[SDLK_DOWN]) input.pad[joynum] |= INPUT_DOWN;
if(keystate[SDLK_LEFT]) input.pad[joynum] |= INPUT_LEFT;
else
if(keystate[SDLK_RIGHT]) input.pad[joynum] |= INPUT_RIGHT;
break;
}
}
return 1;
}
int main (int argc, char **argv)
{
FILE *fp;
int running = 1;
/* Print help if no game specified */
if(argc < 2)
{
char caption[256];
sprintf(caption, "Genesis Plus GX\\SDL\nusage: %s gamename\n", argv[0]);
MessageBox(NULL, caption, "Information", 0);
return 1;
}
/* set default config */
error_init();
set_config_defaults();
/* mark all BIOS as unloaded */
system_bios = 0;
/* Genesis BOOT ROM support (2KB max) */
memset(boot_rom, 0xFF, 0x800);
fp = fopen(MD_BIOS, "rb");
if (fp != NULL)
{
int i;
/* read BOOT ROM */
fread(boot_rom, 1, 0x800, fp);
fclose(fp);
/* check BOOT ROM */
if (!memcmp((char *)(boot_rom + 0x120),"GENESIS OS", 10))
{
/* mark Genesis BIOS as loaded */
system_bios = SYSTEM_MD;
}
/* Byteswap ROM */
for (i=0; i<0x800; i+=2)
{
uint8 temp = boot_rom[i];
boot_rom[i] = boot_rom[i+1];
boot_rom[i+1] = temp;
}
}
/* initialize SDL */
if(SDL_Init(0) < 0)
{
MessageBox(NULL, "SDL initialization failed", "Error", 0);
return 1;
}
sdl_video_init();
if (use_sound) sdl_sound_init();
sdl_sync_init();
/* initialize Genesis virtual system */
SDL_LockSurface(sdl_video.surf_bitmap);
memset(&bitmap, 0, sizeof(t_bitmap));
bitmap.width = 720;
bitmap.height = 576;
#if defined(USE_8BPP_RENDERING)
bitmap.pitch = (bitmap.width * 1);
#elif defined(USE_15BPP_RENDERING)
bitmap.pitch = (bitmap.width * 2);
#elif defined(USE_16BPP_RENDERING)
bitmap.pitch = (bitmap.width * 2);
#elif defined(USE_32BPP_RENDERING)
bitmap.pitch = (bitmap.width * 4);
#endif
bitmap.data = sdl_video.surf_bitmap->pixels;
SDL_UnlockSurface(sdl_video.surf_bitmap);
bitmap.viewport.changed = 3;
/* Load game file */
if(!load_rom(argv[1]))
{
char caption[256];
sprintf(caption, "Error loading file `%s'.", argv[1]);
MessageBox(NULL, caption, "Error", 0);
return 1;
}
/* initialize system hardware */
audio_init(SOUND_FREQUENCY, 0);
system_init();
/* Mega CD specific */
if (system_hw == SYSTEM_MCD)
{
/* load internal backup RAM */
fp = fopen("./scd.brm", "rb");
if (fp!=NULL)
{
fread(scd.bram, 0x2000, 1, fp);
fclose(fp);
}
/* check if internal backup RAM is formatted */
if (memcmp(scd.bram + 0x2000 - 0x20, brm_format + 0x20, 0x20))
{
/* clear internal backup RAM */
memset(scd.bram, 0x00, 0x200);
/* Internal Backup RAM size fields */
brm_format[0x10] = brm_format[0x12] = brm_format[0x14] = brm_format[0x16] = 0x00;
brm_format[0x11] = brm_format[0x13] = brm_format[0x15] = brm_format[0x17] = (sizeof(scd.bram) / 64) - 3;
/* format internal backup RAM */
memcpy(scd.bram + 0x2000 - 0x40, brm_format, 0x40);
}
/* load cartridge backup RAM */
if (scd.cartridge.id)
{
fp = fopen("./cart.brm", "rb");
if (fp!=NULL)
{
fread(scd.cartridge.area, scd.cartridge.mask + 1, 1, fp);
fclose(fp);
}
/* check if cartridge backup RAM is formatted */
if (memcmp(scd.cartridge.area + scd.cartridge.mask + 1 - 0x20, brm_format + 0x20, 0x20))
{
/* clear cartridge backup RAM */
memset(scd.cartridge.area, 0x00, scd.cartridge.mask + 1);
/* Cartridge Backup RAM size fields */
brm_format[0x10] = brm_format[0x12] = brm_format[0x14] = brm_format[0x16] = (((scd.cartridge.mask + 1) / 64) - 3) >> 8;
brm_format[0x11] = brm_format[0x13] = brm_format[0x15] = brm_format[0x17] = (((scd.cartridge.mask + 1) / 64) - 3) & 0xff;
/* format cartridge backup RAM */
memcpy(scd.cartridge.area + scd.cartridge.mask + 1 - sizeof(brm_format), brm_format, sizeof(brm_format));
}
}
}
if (sram.on)
{
/* load SRAM */
fp = fopen("./game.srm", "rb");
if (fp!=NULL)
{
fread(sram.sram,0x10000,1, fp);
fclose(fp);
}
}
/* reset system hardware */
system_reset();
if(use_sound) SDL_PauseAudio(0);
/* 3 frames = 50 ms (60hz) or 60 ms (50hz) */
if(sdl_sync.sem_sync)
SDL_SetTimer(vdp_pal ? 60 : 50, sdl_sync_timer_callback);
/* emulation loop */
while(running)
{
SDL_Event event;
if (SDL_PollEvent(&event))
{
switch(event.type)
{
case SDL_USEREVENT:
{
char caption[100];
sprintf(caption,"Genesis Plus GX - %d fps - %s", event.user.code, (rominfo.international[0] != 0x20) ? rominfo.international : rominfo.domestic);
SDL_WM_SetCaption(caption, NULL);
break;
}
case SDL_QUIT:
{
running = 0;
break;
}
case SDL_KEYDOWN:
{
running = sdl_control_update(event.key.keysym.sym);
break;
}
}
}
sdl_video_update();
sdl_sound_update(use_sound);
if(!turbo_mode && sdl_sync.sem_sync && sdl_video.frames_rendered % 3 == 0)
{
SDL_SemWait(sdl_sync.sem_sync);
}
}
if (system_hw == SYSTEM_MCD)
{
/* save internal backup RAM (if formatted) */
if (!memcmp(scd.bram + 0x2000 - 0x20, brm_format + 0x20, 0x20))
{
fp = fopen("./scd.brm", "wb");
if (fp!=NULL)
{
fwrite(scd.bram, 0x2000, 1, fp);
fclose(fp);
}
}
/* save cartridge backup RAM (if formatted) */
if (scd.cartridge.id)
{
if (!memcmp(scd.cartridge.area + scd.cartridge.mask + 1 - 0x20, brm_format + 0x20, 0x20))
{
fp = fopen("./cart.brm", "wb");
if (fp!=NULL)
{
fwrite(scd.cartridge.area, scd.cartridge.mask + 1, 1, fp);
fclose(fp);
}
}
}
}
if (sram.on)
{
/* save SRAM */
fp = fopen("./game.srm", "wb");
if (fp!=NULL)
{
fwrite(sram.sram,0x10000,1, fp);
fclose(fp);
}
}
audio_shutdown();
error_shutdown();
sdl_video_close();
sdl_sound_close();
sdl_sync_close();
SDL_Quit();
return 0;
}