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sms, memory mapping improvements

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This commit is contained in:
kub 2021-10-08 19:34:15 +02:00
parent 47ea630f6d
commit 032c76a3a2
4 changed files with 69 additions and 41 deletions
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90
pico/sms.c
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@ -8,7 +8,6 @@
/*
* TODO:
* - start in a state as if BIOS ran
* - RAM support in mapper
* - region support
* - H counter
*/
@ -231,7 +230,8 @@ static void write_sram(unsigned short a, unsigned char d)
Pico.sv.data[a] = d;
}
static void write_bank(unsigned short a, unsigned char d)
// 16KB bank mapping for Sega mapper
static void write_bank_sega(unsigned short a, unsigned char d)
{
elprintf(EL_Z80BNK, "bank %04x %02x @ %04x", a, d, z80_pc());
Pico.ms.carthw[a & 0x0f] = d;
@ -240,16 +240,10 @@ static void write_bank(unsigned short a, unsigned char d)
case 0x0d:
d &= bank_mask;
z80_map_set(z80_read_map, 0x0400, 0x3fff, Pico.rom+0x400 + (d << 14), 0);
#ifdef _USE_CZ80
Cz80_Set_Fetch(&CZ80, 0x0400, 0x3fff, (FPTR)Pico.rom+0x400 + (d << 14));
#endif
break;
case 0x0e:
d &= bank_mask;
z80_map_set(z80_read_map, 0x4000, 0x7fff, Pico.rom + (d << 14), 0);
#ifdef _USE_CZ80
Cz80_Set_Fetch(&CZ80, 0x4000, 0x7fff, (FPTR)Pico.rom + (d << 14));
#endif
break;
case 0x0c:
@ -260,39 +254,50 @@ static void write_bank(unsigned short a, unsigned char d)
if (Pico.ms.carthw[0xc] & 0x08) {
d = (Pico.ms.carthw[0xc] & 0x04) >> 2;
z80_map_set(z80_read_map, 0x8000, 0xbfff, Pico.sv.data + d*0x4000, 0);
#ifdef _USE_CZ80
Cz80_Set_Fetch(&CZ80, 0x8000, 0xbfff, (FPTR)Pico.sv.data + d*0x4000);
#endif
z80_map_set(z80_write_map, 0x8000, 0xbfff, write_sram, 1);
} else {
d = Pico.ms.carthw[0xf] & bank_mask;
z80_map_set(z80_read_map, 0x8000, 0xbfff, Pico.rom + (d << 14), 0);
#ifdef _USE_CZ80
Cz80_Set_Fetch(&CZ80, 0x8000, 0xbfff, (FPTR)Pico.rom + (d << 14));
#endif
z80_map_set(z80_write_map, 0x8000, 0xbfff, xwrite, 1);
}
break;
}
}
// 8KB ROM mapping for MSX mapper
static void write_bank_msx(unsigned short a, unsigned char d)
{
Pico.ms.mapper = 1; // TODO define (more) mapper types
Pico.ms.carthw[a] = d;
a = (a^2)*0x2000 + 0x4000;
d &= 2*bank_mask + 1;
z80_map_set(z80_read_map, a, a+0x1fff, Pico.rom + (d << 13), 0);
}
// TODO mapping is currently auto-selecting, but that's not very reliable.
static void xwrite(unsigned int a, unsigned char d)
{
elprintf(EL_IO, "z80 write [%04x] %02x", a, d);
if (a >= 0xc000)
PicoMem.zram[a & 0x1fff] = d;
if (a >= 0xfff8)
write_bank(a, d);
// codemasters
if (a == 0x0000)
write_bank(0xfffd, d);
// Sega. Maps 4 bank 16KB each
if (a >= 0xfff8 /*&& !Pico.ms.mapper*/)
write_bank_sega(a, d);
// Codemasters. Similar to Sega, but different addresses
if (a == 0x0000 && !Pico.ms.mapper)
write_bank_sega(0xfffd, d);
if (a == 0x4000)
write_bank(0xfffe, d);
write_bank_sega(0xfffe, d);
if (a == 0x8000)
write_bank(0xffff, d);
// korean
write_bank_sega(0xffff, d);
// Korean. 1 selectable 16KB bank at the top
if (a == 0xa000)
write_bank(0xffff, d);
write_bank_sega(0xffff, d);
// MSX. 4 selectable 8KB banks at the top
if (a <= 0x0003 && (a || Pico.ms.mapper))
write_bank_msx(a, d);
}
void PicoResetMS(void)
@ -300,6 +305,10 @@ void PicoResetMS(void)
z80_reset();
PsndReset(); // pal must be known here
ymflag = 0xffff;
Pico.m.dirtyPal = 1;
// reset memory mapping
PicoMemSetupMS();
}
void PicoPowerMS(void)
@ -321,11 +330,6 @@ void PicoPowerMS(void)
tmp = 1 << s;
bank_mask = (tmp - 1) >> 14;
Pico.ms.carthw[0x0c] = 0;
Pico.ms.carthw[0x0d] = 0;
Pico.ms.carthw[0x0e] = 1;
Pico.ms.carthw[0x0f] = 2;
PicoReset();
}
@ -344,20 +348,36 @@ void PicoMemSetupMS(void)
drZ80.z80_out = z80_sms_out;
#endif
#ifdef _USE_CZ80
Cz80_Set_Fetch(&CZ80, 0x0000, 0xbfff, (FPTR)Pico.rom);
Cz80_Set_Fetch(&CZ80, 0xc000, 0xdfff, (FPTR)PicoMem.zram);
Cz80_Set_Fetch(&CZ80, 0xe000, 0xffff, (FPTR)PicoMem.zram);
Cz80_Set_INPort(&CZ80, z80_sms_in);
Cz80_Set_OUTPort(&CZ80, z80_sms_out);
#endif
// memory mapper setup, linearly mapped, default is Sega mapper
Pico.ms.carthw[0x00] = 4;
Pico.ms.carthw[0x01] = 5;
Pico.ms.carthw[0x02] = 2;
Pico.ms.carthw[0x03] = 3;
Pico.ms.carthw[0x0c] = 0;
Pico.ms.carthw[0x0d] = 0;
Pico.ms.carthw[0x0e] = 1;
Pico.ms.carthw[0x0f] = 2;
Pico.ms.mapper = 0;
}
void PicoStateLoadedMS(void)
{
write_bank(0xfffc, Pico.ms.carthw[0x0c]);
write_bank(0xfffd, Pico.ms.carthw[0x0d]);
write_bank(0xfffe, Pico.ms.carthw[0x0e]);
write_bank(0xffff, Pico.ms.carthw[0x0f]);
if (Pico.ms.mapper) {
xwrite(0x0000, Pico.ms.carthw[0]);
xwrite(0x0001, Pico.ms.carthw[1]);
xwrite(0x0002, Pico.ms.carthw[2]);
xwrite(0x0003, Pico.ms.carthw[3]);
} else {
xwrite(0xfffc, Pico.ms.carthw[0x0c]);
xwrite(0xfffd, Pico.ms.carthw[0x0d]);
xwrite(0xfffe, Pico.ms.carthw[0x0e]);
xwrite(0xffff, Pico.ms.carthw[0x0f]);
}
}
void PicoFrameMS(void)