The-Homebrew-Cloud/Genesis-Plus-GX
2
0
Fork 0
mirror of https://github.com/ekeeke/Genesis-Plus-GX.git synced 2024-11-04 18:05:06 +01:00
Code Issues Packages Projects Releases Wiki Activity

BIOS support (continued)

Browse Source
This commit is contained in:
ekeeke31 2012-01-15 19:55:22 +00:00
parent 892abc8589
commit b051d03f86
1 changed files with 31 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
source/loadrom.c
View File

@ -303,6 +303,8 @@ static void getrominfo(char *romheader)
} }
else else
{ {
int i,j;
/* Some SMS games don't have any header */ /* Some SMS games don't have any header */
if (system_hw != SYSTEM_MD) return; if (system_hw != SYSTEM_MD) return;
@ -312,7 +314,7 @@ static void getrominfo(char *romheader)
/* Domestic (japanese) name */ /* Domestic (japanese) name */
rominfo.domestic[0] = romheader[ROMDOMESTIC]; rominfo.domestic[0] = romheader[ROMDOMESTIC];
int i, j = 1; j = 1;
for (i=1; i<48; i++) for (i=1; i<48; i++)
{ {
if ((rominfo.domestic[j-1] != 32) || (romheader[ROMDOMESTIC + i] != 32)) if ((rominfo.domestic[j-1] != 32) || (romheader[ROMDOMESTIC + i] != 32))
@ -393,17 +395,17 @@ int load_rom(char *filename)
if (!size) return(0); if (!size) return(0);
/* Auto-detect system mode from ROM file extension */ /* Auto-detect system mode from ROM file extension */
if (!strnicmp(".sms", &filename[strlen(filename) - 4], 4)) if (!strncmp(".sms", &filename[strlen(filename) - 4], 4))
{ {
/* Master System II hardware */ /* Master System II hardware */
system_hw = SYSTEM_SMS2; system_hw = SYSTEM_SMS2;
} }
else if (!strnicmp(".gg", &filename[strlen(filename) - 3], 3)) else if (!strncmp(".gg", &filename[strlen(filename) - 3], 3))
{ {
/* Game Gear hardware (GG mode) */ /* Game Gear hardware (GG mode) */
system_hw = SYSTEM_GG; system_hw = SYSTEM_GG;
} }
else if (!strnicmp(".sg", &filename[strlen(filename) - 3], 3)) else if (!strncmp(".sg", &filename[strlen(filename) - 3], 3))
{ {
/* SG-1000 hardware */ /* SG-1000 hardware */
system_hw = SYSTEM_SG; system_hw = SYSTEM_SG;
@ -414,7 +416,7 @@ int load_rom(char *filename)
system_hw = SYSTEM_MD; system_hw = SYSTEM_MD;
/* Decode .MDX format */ /* Decode .MDX format */
if (!strnicmp(".mdx", &filename[strlen(filename) - 4], 4)) if (!strncmp(".mdx", &filename[strlen(filename) - 4], 4))
{ {
for (i = 4; i < size - 1; i++) for (i = 4; i < size - 1; i++)
{ {
@ -444,9 +446,6 @@ int load_rom(char *filename)
if (size > MAXROMSIZE) size = MAXROMSIZE; if (size > MAXROMSIZE) size = MAXROMSIZE;
cart.romsize = size; cart.romsize = size;
/* clear unused ROM space */
memset(cart.rom + size, 0xff, MAXROMSIZE - size);
/* get infos from ROM header */ /* get infos from ROM header */
getrominfo((char *)cart.rom); getrominfo((char *)cart.rom);
@ -456,9 +455,6 @@ int load_rom(char *filename)
system_hw = SYSTEM_PICO; system_hw = SYSTEM_PICO;
} }
/* detect console region */
region_autodetect();
/* Save ROM type for later use */ /* Save ROM type for later use */
romtype = system_hw; romtype = system_hw;
@ -484,13 +480,16 @@ int load_rom(char *filename)
system_hw = config.system; system_hw = config.system;
} }
/* set console region */
region_autodetect();
/* Genesis mode specific */ /* Genesis mode specific */
if (system_hw == SYSTEM_MD) if (system_hw == SYSTEM_MD)
{ {
#ifdef LSB_FIRST #ifdef LSB_FIRST
/* Byteswap ROM to optimize 16-bit access */ /* Byteswap ROM to optimize 16-bit access */
uint8 temp; uint8 temp;
for(i = 0; i < size; i += 2) for (i = 0; i < size; i += 2)
{ {
temp = cart.rom[i]; temp = cart.rom[i];
cart.rom[i] = cart.rom[i+1]; cart.rom[i] = cart.rom[i+1];
@ -512,6 +511,13 @@ int load_rom(char *filename)
} }
} }
/* Master System or Game Gear BIOS ROM are loaded within $400000-$4FFFFF area */
if (size > 0x400000)
{
/* Mark both BIOS as unloaded if loaded ROM is overwriting them */
config.bios &= ~(SYSTEM_SMS | SYSTEM_GG);
}
return(1); return(1);
} }
@ -531,19 +537,23 @@ void region_autodetect(void)
{ {
/* country codes used to differentiate region */ /* country codes used to differentiate region */
/* 0001 = japan ntsc (1) */ /* 0001 = japan ntsc (1) */
/* 0010 = japan pal (2) */ /* 0010 = japan pal (2) -> does not exist ? */
/* 0100 = usa (4) */ /* 0100 = usa (4) */
/* 1000 = europe (8) */ /* 1000 = europe (8) */
int country = 0; int country = 0;
int i = 0;
char c;
/* from Gens */ /* from Gens */
if (!strnicmp(rominfo.country, "eur", 3)) country |= 8; if (!strncmp(rominfo.country, "eur", 3)) country |= 8;
else if (!strnicmp(rominfo.country, "usa", 3)) country |= 4; else if (!strncmp(rominfo.country, "EUR", 3)) country |= 8;
else if (!strnicmp(rominfo.country, "jap", 3)) country |= 1; else if (!strncmp(rominfo.country, "jap", 3)) country |= 1;
else if (!strncmp(rominfo.country, "JAP", 3)) country |= 1;
else if (!strncmp(rominfo.country, "usa", 3)) country |= 4;
else if (!strncmp(rominfo.country, "USA", 3)) country |= 4;
else else
{ {
int i;
char c;
/* look for each characters */ /* look for each characters */
for(i = 0; i < 4; i++) for(i = 0; i < 4; i++)
{ {
@ -590,7 +600,7 @@ void region_autodetect(void)
else if (config.region_detect == 4) region_code = REGION_JAPAN_PAL; else if (config.region_detect == 4) region_code = REGION_JAPAN_PAL;
/* PAL/NTSC timings */ /* PAL/NTSC timings */
vdp_pal = (region_code & REGION_JAPAN_PAL) >> 6; vdp_pal = (region_code >> 6) & 0x01;
} }