bsnes/sfc/cpu/mmio/mmio.cpp

521 lines
12 KiB
C++

auto CPU::pio() -> uint8 {
return status.pio;
}
auto CPU::joylatch() -> bool {
return status.joypad_strobe_latch;
}
//WMDATA
auto CPU::mmio_r2180() -> uint8 {
return bus.read(0x7e0000 | status.wram_addr++, regs.mdr);
}
//WMDATA
auto CPU::mmio_w2180(uint8 data) -> void {
bus.write(0x7e0000 | status.wram_addr++, data);
}
//WMADDL
auto CPU::mmio_w2181(uint8 data) -> void {
status.wram_addr = (status.wram_addr & 0x01ff00) | (data << 0);
}
//WMADDM
auto CPU::mmio_w2182(uint8 data) -> void {
status.wram_addr = (status.wram_addr & 0x0100ff) | (data << 8);
}
//WMADDH
auto CPU::mmio_w2183(uint8 data) -> void {
status.wram_addr = (status.wram_addr & 0x00ffff) | (data << 16);
}
//JOYSER0
//bit 0 is shared between JOYSER0 and JOYSER1, therefore
//strobing $4016.d0 affects both controller port latches.
//$4017 bit 0 writes are ignored.
auto CPU::mmio_w4016(uint8 data) -> void {
device.controllerPort1->latch(data & 1);
device.controllerPort2->latch(data & 1);
}
//JOYSER0
//7-2 = MDR
//1-0 = Joypad serial data
auto CPU::mmio_r4016() -> uint8 {
uint8 r = regs.mdr & 0xfc;
r |= device.controllerPort1->data();
return r;
}
//JOYSER1
//7-5 = MDR
//4-2 = Always 1 (pins are connected to GND)
//1-0 = Joypad serial data
auto CPU::mmio_r4017() -> uint8 {
uint8 r = (regs.mdr & 0xe0) | 0x1c;
r |= device.controllerPort2->data();
return r;
}
//NMITIMEN
auto CPU::mmio_w4200(uint8 data) -> void {
status.auto_joypad_poll = data & 1;
nmitimen_update(data);
}
//WRIO
auto CPU::mmio_w4201(uint8 data) -> void {
if((status.pio & 0x80) && !(data & 0x80)) ppu.latch_counters();
status.pio = data;
}
//WRMPYA
auto CPU::mmio_w4202(uint8 data) -> void {
status.wrmpya = data;
}
//WRMPYB
auto CPU::mmio_w4203(uint8 data) -> void {
status.rdmpy = 0;
if(alu.mpyctr || alu.divctr) return;
status.wrmpyb = data;
status.rddiv = (status.wrmpyb << 8) | status.wrmpya;
alu.mpyctr = 8; //perform multiplication over the next eight cycles
alu.shift = status.wrmpyb;
}
//WRDIVL
auto CPU::mmio_w4204(uint8 data) -> void {
status.wrdiva = (status.wrdiva & 0xff00) | (data << 0);
}
//WRDIVH
auto CPU::mmio_w4205(uint8 data) -> void {
status.wrdiva = (status.wrdiva & 0x00ff) | (data << 8);
}
//WRDIVB
auto CPU::mmio_w4206(uint8 data) -> void {
status.rdmpy = status.wrdiva;
if(alu.mpyctr || alu.divctr) return;
status.wrdivb = data;
alu.divctr = 16; //perform division over the next sixteen cycles
alu.shift = status.wrdivb << 16;
}
//HTIMEL
auto CPU::mmio_w4207(uint8 data) -> void {
status.hirq_pos = (status.hirq_pos & 0x0100) | (data << 0);
}
//HTIMEH
auto CPU::mmio_w4208(uint8 data) -> void {
status.hirq_pos = (status.hirq_pos & 0x00ff) | (data << 8);
}
//VTIMEL
auto CPU::mmio_w4209(uint8 data) -> void {
status.virq_pos = (status.virq_pos & 0x0100) | (data << 0);
}
//VTIMEH
auto CPU::mmio_w420a(uint8 data) -> void {
status.virq_pos = (status.virq_pos & 0x00ff) | (data << 8);
}
//DMAEN
auto CPU::mmio_w420b(uint8 data) -> void {
for(unsigned i = 0; i < 8; i++) {
channel[i].dma_enabled = data & (1 << i);
}
if(data) status.dma_pending = true;
}
//HDMAEN
auto CPU::mmio_w420c(uint8 data) -> void {
for(unsigned i = 0; i < 8; i++) {
channel[i].hdma_enabled = data & (1 << i);
}
}
//MEMSEL
auto CPU::mmio_w420d(uint8 data) -> void {
status.rom_speed = (data & 1 ? 6 : 8);
}
//RDNMI
//7 = NMI acknowledge
//6-4 = MDR
//3-0 = CPU (5a22) version
auto CPU::mmio_r4210() -> uint8 {
uint8 r = (regs.mdr & 0x70);
r |= (uint8)(rdnmi()) << 7;
r |= (cpu_version & 0x0f);
return r;
}
//TIMEUP
//7 = IRQ acknowledge
//6-0 = MDR
auto CPU::mmio_r4211() -> uint8 {
uint8 r = (regs.mdr & 0x7f);
r |= (uint8)(timeup()) << 7;
return r;
}
//HVBJOY
//7 = VBLANK acknowledge
//6 = HBLANK acknowledge
//5-1 = MDR
//0 = JOYPAD acknowledge
auto CPU::mmio_r4212() -> uint8 {
uint8 r = (regs.mdr & 0x3e);
if(status.auto_joypad_active) r |= 0x01;
if(hcounter() <= 2 || hcounter() >= 1096) r |= 0x40; //hblank
if(vcounter() >= (ppu.overscan() == false ? 225 : 240)) r |= 0x80; //vblank
return r;
}
//RDIO
auto CPU::mmio_r4213() -> uint8 {
return status.pio;
}
//RDDIVL
auto CPU::mmio_r4214() -> uint8 {
return status.rddiv >> 0;
}
//RDDIVH
auto CPU::mmio_r4215() -> uint8 {
return status.rddiv >> 8;
}
//RDMPYL
auto CPU::mmio_r4216() -> uint8 {
return status.rdmpy >> 0;
}
//RDMPYH
auto CPU::mmio_r4217() -> uint8 {
return status.rdmpy >> 8;
}
auto CPU::mmio_r4218() -> uint8 { return status.joy1 >> 0; } //JOY1L
auto CPU::mmio_r4219() -> uint8 { return status.joy1 >> 8; } //JOY1H
auto CPU::mmio_r421a() -> uint8 { return status.joy2 >> 0; } //JOY2L
auto CPU::mmio_r421b() -> uint8 { return status.joy2 >> 8; } //JOY2H
auto CPU::mmio_r421c() -> uint8 { return status.joy3 >> 0; } //JOY3L
auto CPU::mmio_r421d() -> uint8 { return status.joy3 >> 8; } //JOY3H
auto CPU::mmio_r421e() -> uint8 { return status.joy4 >> 0; } //JOY4L
auto CPU::mmio_r421f() -> uint8 { return status.joy4 >> 8; } //JOY4H
//DMAPx
auto CPU::mmio_r43x0(uint8 i) -> uint8 {
return (channel[i].direction << 7)
| (channel[i].indirect << 6)
| (channel[i].unused << 5)
| (channel[i].reverse_transfer << 4)
| (channel[i].fixed_transfer << 3)
| (channel[i].transfer_mode << 0);
}
//BBADx
auto CPU::mmio_r43x1(uint8 i) -> uint8 {
return channel[i].dest_addr;
}
//A1TxL
auto CPU::mmio_r43x2(uint8 i) -> uint8 {
return channel[i].source_addr >> 0;
}
//A1TxH
auto CPU::mmio_r43x3(uint8 i) -> uint8 {
return channel[i].source_addr >> 8;
}
//A1Bx
auto CPU::mmio_r43x4(uint8 i) -> uint8 {
return channel[i].source_bank;
}
//DASxL
//union { uint16 transfer_size; uint16 indirect_addr; };
auto CPU::mmio_r43x5(uint8 i) -> uint8 {
return channel[i].transfer_size >> 0;
}
//DASxH
//union { uint16 transfer_size; uint16 indirect_addr; };
auto CPU::mmio_r43x6(uint8 i) -> uint8 {
return channel[i].transfer_size >> 8;
}
//DASBx
auto CPU::mmio_r43x7(uint8 i) -> uint8 {
return channel[i].indirect_bank;
}
//A2AxL
auto CPU::mmio_r43x8(uint8 i) -> uint8 {
return channel[i].hdma_addr >> 0;
}
//A2AxH
auto CPU::mmio_r43x9(uint8 i) -> uint8 {
return channel[i].hdma_addr >> 8;
}
//NTRLx
auto CPU::mmio_r43xa(uint8 i) -> uint8 {
return channel[i].line_counter;
}
//???
auto CPU::mmio_r43xb(uint8 i) -> uint8 {
return channel[i].unknown;
}
//DMAPx
auto CPU::mmio_w43x0(uint8 i, uint8 data) -> void {
channel[i].direction = data & 0x80;
channel[i].indirect = data & 0x40;
channel[i].unused = data & 0x20;
channel[i].reverse_transfer = data & 0x10;
channel[i].fixed_transfer = data & 0x08;
channel[i].transfer_mode = data & 0x07;
}
//DDBADx
auto CPU::mmio_w43x1(uint8 i, uint8 data) -> void {
channel[i].dest_addr = data;
}
//A1TxL
auto CPU::mmio_w43x2(uint8 i, uint8 data) -> void {
channel[i].source_addr = (channel[i].source_addr & 0xff00) | (data << 0);
}
//A1TxH
auto CPU::mmio_w43x3(uint8 i, uint8 data) -> void {
channel[i].source_addr = (channel[i].source_addr & 0x00ff) | (data << 8);
}
//A1Bx
auto CPU::mmio_w43x4(uint8 i, uint8 data) -> void {
channel[i].source_bank = data;
}
//DASxL
//union { uint16 transfer_size; uint16 indirect_addr; };
auto CPU::mmio_w43x5(uint8 i, uint8 data) -> void {
channel[i].transfer_size = (channel[i].transfer_size & 0xff00) | (data << 0);
}
//DASxH
//union { uint16 transfer_size; uint16 indirect_addr; };
auto CPU::mmio_w43x6(uint8 i, uint8 data) -> void {
channel[i].transfer_size = (channel[i].transfer_size & 0x00ff) | (data << 8);
}
//DASBx
auto CPU::mmio_w43x7(uint8 i, uint8 data) -> void {
channel[i].indirect_bank = data;
}
//A2AxL
auto CPU::mmio_w43x8(uint8 i, uint8 data) -> void {
channel[i].hdma_addr = (channel[i].hdma_addr & 0xff00) | (data << 0);
}
//A2AxH
auto CPU::mmio_w43x9(uint8 i, uint8 data) -> void {
channel[i].hdma_addr = (channel[i].hdma_addr & 0x00ff) | (data << 8);
}
//NTRLx
auto CPU::mmio_w43xa(uint8 i, uint8 data) -> void {
channel[i].line_counter = data;
}
//???
auto CPU::mmio_w43xb(uint8 i, uint8 data) -> void {
channel[i].unknown = data;
}
auto CPU::mmio_power() -> void {
}
auto CPU::mmio_reset() -> void {
//$2140-217f
for(auto& port : status.port) port = 0x00;
//$2181-$2183
status.wram_addr = 0x000000;
//$4016-$4017
status.joypad_strobe_latch = 0;
status.joypad1_bits = ~0;
status.joypad2_bits = ~0;
//$4200
status.nmi_enabled = false;
status.hirq_enabled = false;
status.virq_enabled = false;
status.auto_joypad_poll = false;
//$4201
status.pio = 0xff;
//$4202-$4203
status.wrmpya = 0xff;
status.wrmpyb = 0xff;
//$4204-$4206
status.wrdiva = 0xffff;
status.wrdivb = 0xff;
//$4207-$420a
status.hirq_pos = 0x01ff;
status.virq_pos = 0x01ff;
//$420d
status.rom_speed = 8;
//$4214-$4217
status.rddiv = 0x0000;
status.rdmpy = 0x0000;
//$4218-$421f
status.joy1 = 0x0000;
status.joy2 = 0x0000;
status.joy3 = 0x0000;
status.joy4 = 0x0000;
//ALU
alu.mpyctr = 0;
alu.divctr = 0;
alu.shift = 0;
}
auto CPU::mmio_read(uint addr, uint8 data) -> uint8 {
addr &= 0xffff;
//APU
if((addr & 0xffc0) == 0x2140) { //$2140-$217f
synchronizeSMP();
return smp.portRead(addr);
}
//DMA
if((addr & 0xff80) == 0x4300) { //$4300-$437f
uint i = (addr >> 4) & 7;
switch(addr & 0xf) {
case 0x0: return mmio_r43x0(i);
case 0x1: return mmio_r43x1(i);
case 0x2: return mmio_r43x2(i);
case 0x3: return mmio_r43x3(i);
case 0x4: return mmio_r43x4(i);
case 0x5: return mmio_r43x5(i);
case 0x6: return mmio_r43x6(i);
case 0x7: return mmio_r43x7(i);
case 0x8: return mmio_r43x8(i);
case 0x9: return mmio_r43x9(i);
case 0xa: return mmio_r43xa(i);
case 0xb: return mmio_r43xb(i);
case 0xc: return regs.mdr; //unmapped
case 0xd: return regs.mdr; //unmapped
case 0xe: return regs.mdr; //unmapped
case 0xf: return mmio_r43xb(i); //mirror of $43xb
}
}
switch(addr) {
case 0x2180: return mmio_r2180();
case 0x4016: return mmio_r4016();
case 0x4017: return mmio_r4017();
case 0x4210: return mmio_r4210();
case 0x4211: return mmio_r4211();
case 0x4212: return mmio_r4212();
case 0x4213: return mmio_r4213();
case 0x4214: return mmio_r4214();
case 0x4215: return mmio_r4215();
case 0x4216: return mmio_r4216();
case 0x4217: return mmio_r4217();
case 0x4218: return mmio_r4218();
case 0x4219: return mmio_r4219();
case 0x421a: return mmio_r421a();
case 0x421b: return mmio_r421b();
case 0x421c: return mmio_r421c();
case 0x421d: return mmio_r421d();
case 0x421e: return mmio_r421e();
case 0x421f: return mmio_r421f();
}
return data;
}
auto CPU::mmio_write(uint addr, uint8 data) -> void {
addr &= 0xffff;
//APU
if((addr & 0xffc0) == 0x2140) { //$2140-$217f
synchronizeSMP();
portWrite(addr, data);
return;
}
//DMA
if((addr & 0xff80) == 0x4300) { //$4300-$437f
uint i = (addr >> 4) & 7;
switch(addr & 0xf) {
case 0x0: mmio_w43x0(i, data); return;
case 0x1: mmio_w43x1(i, data); return;
case 0x2: mmio_w43x2(i, data); return;
case 0x3: mmio_w43x3(i, data); return;
case 0x4: mmio_w43x4(i, data); return;
case 0x5: mmio_w43x5(i, data); return;
case 0x6: mmio_w43x6(i, data); return;
case 0x7: mmio_w43x7(i, data); return;
case 0x8: mmio_w43x8(i, data); return;
case 0x9: mmio_w43x9(i, data); return;
case 0xa: mmio_w43xa(i, data); return;
case 0xb: mmio_w43xb(i, data); return;
case 0xc: return; //unmapped
case 0xd: return; //unmapped
case 0xe: return; //unmapped
case 0xf: mmio_w43xb(i, data); return; //mirror of $43xb
}
}
switch(addr) {
case 0x2180: mmio_w2180(data); return;
case 0x2181: mmio_w2181(data); return;
case 0x2182: mmio_w2182(data); return;
case 0x2183: mmio_w2183(data); return;
case 0x4016: mmio_w4016(data); return;
case 0x4017: return; //unmapped
case 0x4200: mmio_w4200(data); return;
case 0x4201: mmio_w4201(data); return;
case 0x4202: mmio_w4202(data); return;
case 0x4203: mmio_w4203(data); return;
case 0x4204: mmio_w4204(data); return;
case 0x4205: mmio_w4205(data); return;
case 0x4206: mmio_w4206(data); return;
case 0x4207: mmio_w4207(data); return;
case 0x4208: mmio_w4208(data); return;
case 0x4209: mmio_w4209(data); return;
case 0x420a: mmio_w420a(data); return;
case 0x420b: mmio_w420b(data); return;
case 0x420c: mmio_w420c(data); return;
case 0x420d: mmio_w420d(data); return;
}
}