* TODO:
* - start in a state as if BIOS ran (partly done for VDP registers, RAM)
* - region support (currently only very limited PAL and Mark-III support)
- * - mappers: EEPROM, some obscure Korean (Nemesis, Janggun)
+ * - mapper for EEPROM support
*/
#include "pico_int.h"
#include "memory.h"
}
}
+
+// ROM/SRAM bank mapping, see https://www.smspower.org/Development/Mappers
+
static int bank_mask;
static void xwrite(unsigned int a, unsigned char d);
-static void write_sram(unsigned short a, unsigned char d)
+
+// Sega mapper. Maps 3 banks 16KB each, with SRAM support
+static void write_sram_sega(unsigned short a, unsigned char d)
{
// SRAM is mapped in 2 16KB banks, selected by bit 2 in control reg
a &= 0x3fff;
Pico.sv.data[a] = d;
}
-// 16KB bank mapping for Sega mapper
static void write_bank_sega(unsigned short a, unsigned char d)
{
+ if (a < 0xfff8) return;
// avoid mapper detection for RAM fill with 0
if (Pico.ms.mapper != PMS_MAP_SEGA && (Pico.ms.mapper || d == 0)) return;
- elprintf(EL_Z80BNK, "bank 16k %04x %02x @ %04x", a, d, z80_pc());
+
+ elprintf(EL_Z80BNK, "bank sega %04x %02x @ %04x", a, d, z80_pc());
Pico.ms.mapper = PMS_MAP_SEGA;
Pico.ms.carthw[a & 0x0f] = 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);
- z80_map_set(z80_write_map, 0x8000, 0xbfff, write_sram, 1);
+ z80_map_set(z80_write_map, 0x8000, 0xbfff, write_sram_sega, 1);
} else {
d = Pico.ms.carthw[0xf] & bank_mask;
z80_map_set(z80_read_map, 0x8000, 0xbfff, Pico.rom + (d << 14), 0);
}
}
-// 16KB bank mapping for Codemasters mapper, TODO: SRAM support
+// Codemasters mapper. Similar to Sega, but different addresses, TODO: SRAM
static void write_bank_codem(unsigned short a, unsigned char d)
{
- // don't detect @0x0 to avoid confusing with MSX
- if (Pico.ms.mapper != PMS_MAP_CODEM && (Pico.ms.mapper || (a|d) == 0)) return;
- elprintf(EL_Z80BNK, "bank 16k %04x %02x @ %04x", a, d, z80_pc());
+ if (a >= 0xc000 || (a & 0x3fff)) return; // address is 0x0000, 0x4000, 0x8000?
+ // don't detect linear mapping to avoid confusing with MSX
+ if (Pico.ms.mapper != PMS_MAP_CODEM && (Pico.ms.mapper || (a>>14) == d)) return;
+ elprintf(EL_Z80BNK, "bank codem %04x %02x @ %04x", a, d, z80_pc());
Pico.ms.mapper = PMS_MAP_CODEM;
Pico.ms.carthw[a>>14] = d;
z80_map_set(z80_read_map, a, a+0x3fff, Pico.rom + (d << 14), 0);
}
-// 8KB bank mapping for MSX mapper
+// MSX mapper. 4 selectable 8KB banks at the top
static void write_bank_msx(unsigned short a, unsigned char d)
{
- // don't detect @0x0 to avoid confusing with Codemasters
+ if (a > 0x0003) return;
+ // don't detect linear mapping to avoid confusing with Codemasters
if (Pico.ms.mapper != PMS_MAP_MSX && (Pico.ms.mapper || (a|d) == 0)) return;
- elprintf(EL_Z80BNK, "bank 8k %04x %02x @ %04x", a, d, z80_pc());
+ elprintf(EL_Z80BNK, "bank msx %04x %02x @ %04x", a, d, z80_pc());
Pico.ms.mapper = PMS_MAP_MSX;
Pico.ms.carthw[a] = d;
z80_map_set(z80_read_map, a, a+0x1fff, Pico.rom + (d << 13), 0);
}
-// 32KB bank mapping for Korean n-in-1 packs
+// Korea mapping, 1 selectable 16KB bank at the top
+static void write_bank_korea(unsigned short a, unsigned char d)
+{
+ if (a != 0xa000) return;
+ if (Pico.ms.mapper != PMS_MAP_KOREA && (Pico.ms.mapper)) return;
+ elprintf(EL_Z80BNK, "bank korea %04x %02x @ %04x", a, d, z80_pc());
+ Pico.ms.mapper = PMS_MAP_KOREA;
+ Pico.ms.carthw[0xf] = d;
+
+ d &= bank_mask;
+ z80_map_set(z80_read_map, 0x8000, 0xbfff, Pico.rom + (d << 14), 0);
+}
+
+// Korean n-in-1 mapping. 1 selectable 32KB bank at the bottom
static void write_bank_n32k(unsigned short a, unsigned char d)
{
+ if (a != 0xffff) return;
// code must be in RAM since all visible ROM space is swapped
if (Pico.ms.mapper != PMS_MAP_N32K && (Pico.ms.mapper || z80_pc() < 0xc000)) return;
elprintf(EL_Z80BNK, "bank 32k %04x %02x @ %04x", a, d, z80_pc());
z80_map_set(z80_read_map, 0, 0x7fff, Pico.rom + (d << 15), 0);
}
-// 16KB bank mapping for Korean n-in-1 packs
+// Korean 4-in-1. 2 selectable 16KB banks, top bank is shifted by bottom one
static void write_bank_n16k(unsigned short a, unsigned char d)
{
+ if (a != 0x3ffe && a != 0x7fff && a != 0xbfff) return;
// code must be in RAM since all visible ROM space is swapped
if (Pico.ms.mapper != PMS_MAP_N16K && (Pico.ms.mapper || z80_pc() < 0xc000)) return;
elprintf(EL_Z80BNK, "bank 16k %04x %02x @ %04x", a, d, z80_pc());
z80_map_set(z80_read_map, a, a+0x3fff, Pico.rom + (d << 14), 0);
}
-// TODO mapping is currently auto-selecting, but that's not totally reliable.
+// MSX-Nemesis mapper. 4 selectable 8KB banks at the top
+static void write_bank_msxn(unsigned short a, unsigned char d)
+{
+ if (a > 0x0003) return;
+ // never autodetected, selectable only via config
+ if (Pico.ms.mapper != PMS_MAP_NEMESIS) return;
+ elprintf(EL_Z80BNK, "bank nems %04x %02x @ %04x", a, d, z80_pc());
+ 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);
+}
+
+// Korean Janggun mapper. 4 selectable 8KB banks at the top, hardware byte flip
+static unsigned char read_flipped_jang(unsigned a)
+{
+ static unsigned char flipper[16] = // reversed nibble bit order
+ { 0x0,0x8,0x4,0xc,0x2,0xa,0x6,0xe,0x1,0x9,0x5,0xd,0x3,0xb,0x7,0xf };
+ unsigned char c;
+
+ // return value at address a in reversed bit order
+ c = Pico.rom[(Pico.ms.carthw[a>>13] << 13) + (a & 0x1fff)];
+ return (flipper[c&0xf]<<4) | flipper[c>>4];
+}
+
+static void write_bank_jang(unsigned short a, unsigned char d)
+{
+ // address is 0xfffe, 0xffff, 0x4000, 0x6000, 0x8000, 0xa000
+ if ((a|1) != 0xffff && (!((a^(a<<1)) & 0x8000) || (a & 0x1fff))) return;
+ // never autodetected, selectable only via config
+ if (Pico.ms.mapper != PMS_MAP_JANGGUN) return;
+ elprintf(EL_Z80BNK, "bank jang %04x %02x @ %04x", a, d, z80_pc());
+
+ if ((a|1) == 0xffff) {
+ int x = a & 1, f = d & 0x40;
+ Pico.ms.carthw[x] = d;
+ d &= bank_mask;
+ Pico.ms.carthw[2*x + 2] = 2*d, Pico.ms.carthw[2*x + 3] = 2*d+1;
+ a = (x+1) * 0x4000;
+ if (!f)
+ z80_map_set(z80_read_map, a, a+0x3fff, Pico.rom + (d << 14), 0);
+ else
+ z80_map_set(z80_read_map, a, a+0x3fff, read_flipped_jang, 1);
+ } else {
+ d &= 2*bank_mask + 1;
+ Pico.ms.carthw[a>>13] = d;
+ if (!(Pico.ms.carthw[(a>>15)&1] & 0x40))
+ z80_map_set(z80_read_map, a, a+0x1fff, Pico.rom + (d << 13), 0);
+ else
+ z80_map_set(z80_read_map, a, a+0x1fff, read_flipped_jang, 1);
+ }
+}
+
+// TODO auto-selecting is not really reliable.
// Before adding more mappers this should be revised.
static void xwrite(unsigned int a, unsigned char d)
{
if (a >= 0xc000)
PicoMem.zram[a & 0x1fff] = d;
- // NB the sequence of mappers is crucial for the auto detection
- // Korean n-in-1. 1 selectable 32KB bank at the bottom
- if (a == 0xffff)
- write_bank_n32k(a, d);
- // Sega. Maps 3 banks 16KB each, SRAM
- if (a >= 0xfff8)
- write_bank_sega(a, d);
- // MSX. 4 selectable 8KB banks at the top
- if (a <= 0x0003)
- write_bank_msx(a, d);
- // Codemasters. Similar to Sega, but different addresses
- if (a < 0xc000 && (a & 0x3fff) == 0)
- write_bank_codem(a, d);
- // Korean. 1 selectable 16KB bank at the top
- if (a == 0xa000)
- write_bank_codem(0x8000, d);
- // Korean n-in-1. 2 selectable 16KB banks, top bank has offset from bottom one
- if (a == 0x3ffe || a == 0x7fff || a == 0xbfff)
- write_bank_n16k(a, d);
+ switch (Pico.ms.mapper) { // via config, or auto detected
+ case PMS_MAP_SEGA: write_bank_sega(a, d); break;
+ case PMS_MAP_CODEM: write_bank_codem(a, d); break;
+ case PMS_MAP_MSX: write_bank_msx(a, d); break;
+ case PMS_MAP_KOREA: write_bank_korea(a, d); break;
+ case PMS_MAP_N32K: write_bank_n32k(a, d); break;
+ case PMS_MAP_N16K: write_bank_n16k(a, d); break;
+ case PMS_MAP_JANGGUN: write_bank_jang(a, d); break;
+ case PMS_MAP_NEMESIS: write_bank_msxn(a, d); break;
+
+ case PMS_MAP_AUTO:
+ // NB the sequence of mappers is crucial for the auto detection
+ write_bank_n32k(a, d);
+ write_bank_sega(a, d);
+ write_bank_msx(a, d);
+ write_bank_codem(a, d);
+ write_bank_korea(a, d);
+ write_bank_n16k(a, d);
+ break;
+ }
}
void PicoResetMS(void)
{
- z80_reset();
- PsndReset(); // pal must be known here
- Pico.ms.fm_ctl = 0xff;
- Pico.m.dirtyPal = 1;
+ unsigned tmr;
+ int hw;
+ // set preselected hw/mapper from config
if (PicoIn.hwSelect) {
switch (PicoIn.hwSelect) {
case PHWS_GG: Pico.m.hardware |= 0x1; break;
default: Pico.m.hardware &= ~0x1; break;
}
- } else {
- unsigned tmr;
-
- // check if the ROM header contains more system information to detect GG
- for (tmr = 0x2000; tmr < 0xbfff && tmr <= Pico.romsize; tmr *= 2) {
- if (!memcmp(Pico.rom + tmr-16, "TMR SEGA", 8)) {
- if (Pico.rom[tmr-1] >= 0x50 && Pico.rom[tmr-1] < 0x80)
- Pico.m.hardware |= 0x1;
- break;
- }
+ }
+ if (PicoIn.mapper)
+ Pico.ms.mapper = PicoIn.mapper;
+
+ // check if the ROM header contains more system information
+ for (tmr = 0x2000; tmr < 0xbfff && tmr <= Pico.romsize; tmr *= 2) {
+ if (!memcmp(Pico.rom + tmr-16, "TMR SEGA", 8)) {
+ hw = Pico.rom[tmr-1] >> 4;
+ if (hw >= 0x5 && hw < 0x8 && !PicoIn.hwSelect)
+ Pico.m.hardware |= 0x1; // GG cartridge detected
+ break;
}
}
+ z80_reset();
+ PsndReset(); // pal must be known here
+ Pico.ms.fm_ctl = 0xff;
+ Pico.m.dirtyPal = 1;
+
// reset memory mapping
PicoMemSetupMS();
Pico.video.reg[9] = 0x00;
Pico.video.reg[10] = 0xff;
- // BIOS, clear zram (fake unitialized on japanese NTSC devices)
+ // BIOS, clear zram (unitialized on Mark-III, cf src/mame/drivers/sms.cpp)
memset(PicoMem.zram, PicoIn.regionOverride&1 ? 0xf0:0, sizeof(PicoMem.zram));
}
bank_mask = (tmp - 1) >> 14;
PicoMem.ioports[0] = 0xc3; // hack to jump @0 at end of RAM to wrap around
- Pico.ms.mapper = 0;
+ Pico.ms.mapper = PicoIn.mapper;
PicoReset();
}
z80_map_set(z80_write_map, 0xc000, 0xdfff, PicoMem.zram, 0);
z80_map_set(z80_write_map, 0xe000, 0xffff, xwrite, 1);
+ // Nemesis mapper maps last 8KB rom bank #15 to adress 0
+ if (Pico.ms.mapper == PMS_MAP_NEMESIS && Pico.romsize > 0x1e000)
+ z80_map_set(z80_read_map, 0x0000, 0x1fff, Pico.rom + 0x1e000, 0);
#ifdef _USE_DRZ80
drZ80.z80_in = z80_sms_in;
drZ80.z80_out = z80_sms_out;
// memory mapper setup, linear mapping of 1st 48KB
u8 mapper = Pico.ms.mapper;
- if (Pico.ms.mapper == PMS_MAP_MSX) {
+ if (mapper == PMS_MAP_MSX || mapper == PMS_MAP_NEMESIS) {
xwrite(0x0000, 4);
xwrite(0x0001, 5);
xwrite(0x0002, 2);
xwrite(0x0003, 3);
- } else if (Pico.ms.mapper == PMS_MAP_N32K) {
+ } else if (mapper == PMS_MAP_N32K) {
xwrite(0xffff, 0);
- } else if (Pico.ms.mapper == PMS_MAP_CODEM) {
+ } else if (mapper == PMS_MAP_N16K) {
+ xwrite(0x3ffe, 0);
+ xwrite(0x7fff, 1);
+ xwrite(0xbfff, 2);
+ } else if (mapper == PMS_MAP_JANGGUN) {
+ xwrite(0xfffe, 1);
+ xwrite(0xffff, 2);
+ } else if (mapper == PMS_MAP_CODEM) {
xwrite(0x0000, 0);
xwrite(0x4000, 1);
xwrite(0x8000, 2);
void PicoStateLoadedMS(void)
{
u8 mapper = Pico.ms.mapper;
- if (Pico.ms.mapper == PMS_MAP_MSX) {
+ if (Pico.ms.mapper == PMS_MAP_MSX || Pico.ms.mapper == PMS_MAP_NEMESIS) {
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 if (Pico.ms.mapper == PMS_MAP_N32K) {
xwrite(0xffff, Pico.ms.carthw[0x0f]);
+ } else if (Pico.ms.mapper == PMS_MAP_N16K) {
+ xwrite(0x3ffe, Pico.ms.carthw[0]);
+ xwrite(0x7fff, Pico.ms.carthw[1]);
+ xwrite(0xbfff, Pico.ms.carthw[2]);
+ } else if (Pico.ms.mapper == PMS_MAP_JANGGUN) {
+ xwrite(0x4000, Pico.ms.carthw[2]);
+ xwrite(0x6000, Pico.ms.carthw[3]);
+ xwrite(0x8000, Pico.ms.carthw[4]);
+ xwrite(0xa000, Pico.ms.carthw[5]);
} else if (Pico.ms.mapper == PMS_MAP_CODEM) {
xwrite(0x0000, Pico.ms.carthw[0]);
xwrite(0x4000, Pico.ms.carthw[1]);
notaz.gp2x.de / picodrive.git / commitdiff