libretro/smsplus-gx
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Set VDP Register 1 to 0xE0 after multiple testing.

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Sonic's Edusoft relies on this behaviour and it also works properly when that bit is
set to 0xE0.
(All of the known BIOSes set that bit to 0xE0 before booting a cartridge)

Removing said game hack since it is no longer required.
This commit is contained in:
gameblabla 2019-03-09 10:28:21 +01:00
parent 02a6e57e4e
commit ff1201902b
No known key found for this signature in database
GPG Key ID: B24EFBB23B5F76CB
3 changed files with 3 additions and 14 deletions
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14
source/loadrom.c
View File

@ -22,7 +22,7 @@
#include "shared.h"
#define GAME_DATABASE_CNT 98
#define GAME_DATABASE_CNT 97
typedef struct
{
@ -253,12 +253,7 @@ static rominfo_t game_list[GAME_DATABASE_CNT] =
{0x679E1676, 0, DEVICE_PAD2B, MAPPER_SEGA, DISPLAY_NTSC, TERRITORY_DOMESTIC, CONSOLE_SMS2,
"Wonder Boy III - The dragon's Trap"},
{0x22CCA9BB, 0, DEVICE_PAD2B, MAPPER_SEGA, DISPLAY_NTSC, TERRITORY_DOMESTIC, CONSOLE_SMS2,
"Turma da Monica em O Resgate"},
/* These games break because they expect the vertical interruption bit to be set by default on the VDP, and wait for an interruption before writing any registers to the VDP.
* Only seems to affect Sonic's Edusoft so far. (Other emulators require a SMS BIOS for that game or a hacked binary) */
{0xD9096263, 0, DEVICE_PAD2B, MAPPER_SEGA, DISPLAY_NTSC, TERRITORY_DOMESTIC, CONSOLE_SMS2,
"Sonic's Edusoft"}
"Turma da Monica em O Resgate"}
};
static void set_config()
@ -274,7 +269,6 @@ static void set_config()
sms.device[0] = DEVICE_PAD2B;
sms.device[1] = DEVICE_PAD2B;
sms.use_fm = option.fm;
sms.vdp_register1_default_value = 0x80;
/* console type detection */
/* SMS Header is located at 0x7ff0 */
@ -330,10 +324,6 @@ static void set_config()
/* these games seem to use different gun position calculation method */
sms.gun_offset = 16;
}
if (strcmp(game_list[i].name, "Sonic's Edusoft") == 0)
{
sms.vdp_register1_default_value = 0xA0;
}
i = GAME_DATABASE_CNT;
}
}

1
source/sms.h
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@ -117,7 +117,6 @@ typedef struct
} sio;
uint8_t device[2];
uint8_t gun_offset;
uint8_t vdp_register1_default_value;
} sms_t;
/* BIOS ROM */

2
source/vdp.c
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@ -81,7 +81,7 @@ void vdp_reset(void)
if (IS_SMS && (bios.enabled != 3))
{
vdp.reg[0] = 0x36;
vdp.reg[1] = sms.vdp_register1_default_value;
vdp.reg[1] = 0xE0;
vdp.reg[2] = 0xFF;
vdp.reg[3] = 0xFF;
vdp.reg[4] = 0xFF;