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115 lines
2.8 KiB
C++
115 lines
2.8 KiB
C++
#pragma once
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#include "stdafx.h"
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#include "MMC3.h"
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class MMC3_215 : public MMC3
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{
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private:
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const uint8_t _lutReg[8][8] = {
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 0, 2, 6, 1, 7, 3, 4, 5 },
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{ 0, 5, 4, 1, 7, 2, 6, 3 },
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{ 0, 6, 3, 7, 5, 2, 4, 1 },
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{ 0, 2, 5, 3, 6, 1, 7, 4 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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};
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const uint8_t _lutAddr[8][8] =
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{
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 3, 2, 0, 4, 1, 5, 6, 7 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 5, 0, 1, 2, 3, 7, 6, 4 },
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{ 3, 1, 0, 5, 2, 4, 6, 7 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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{ 0, 1, 2, 3, 4, 5, 6, 7 },
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};
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uint8_t _exRegs[3];
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protected:
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uint16_t RegisterStartAddress() override { return 0x5000; }
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uint16_t RegisterEndAddress() override { return 0xFFFF; }
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void InitMapper() override
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{
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_exRegs[0] = 0;
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_exRegs[1] = 3;
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_exRegs[2] = 0;
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MMC3::InitMapper();
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}
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void StreamState(bool saving) override
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{
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MMC3::StreamState(saving);
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Stream(_exRegs[0], _exRegs[1], _exRegs[2]);
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}
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void SelectCHRPage(uint16_t slot, uint16_t page, ChrMemoryType memoryType) override
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{
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if(_exRegs[0] & 0x40) {
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MMC3::SelectCHRPage(slot, ((_exRegs[1] & 0x0C) << 6) | (page & 0x7F) | ((_exRegs[1] & 0x20) << 2), memoryType);
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} else {
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MMC3::SelectCHRPage(slot, ((_exRegs[1] & 0x0C) << 6) | page, memoryType);
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}
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}
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void SelectPRGPage(uint16_t slot, uint16_t page, PrgMemoryType memoryType = PrgMemoryType::PrgRom) override
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{
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uint8_t sbank = 0;
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uint8_t bank = 0;
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uint8_t mask = 0;
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if(_exRegs[0] & 0x40) {
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mask = 0x0F;
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sbank = (_exRegs[1] & 0x10);
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if(_exRegs[0] & 0x80) {
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bank = ((_exRegs[1] & 0x03) << 4) | (_exRegs[0] & 0x07) | (sbank >> 1);
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}
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} else {
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mask = 0x1F;
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if(_exRegs[0] & 0x80) {
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bank = ((_exRegs[1] & 0x03) << 4) | (_exRegs[0] & 0x0F);
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}
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}
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if(_exRegs[0] & 0x80) {
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bank <<= 1;
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if(_exRegs[0] & 0x20) {
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MMC3::SelectPRGPage(0, bank);
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MMC3::SelectPRGPage(1, bank + 1);
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MMC3::SelectPRGPage(2, bank + 2);
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MMC3::SelectPRGPage(3, bank + 3);
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} else {
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MMC3::SelectPRGPage(0, bank);
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MMC3::SelectPRGPage(1, bank + 1);
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MMC3::SelectPRGPage(2, bank);
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MMC3::SelectPRGPage(3, bank + 1);
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}
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} else {
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MMC3::SelectPRGPage(slot, ((_exRegs[1] & 0x03) << 5) | (page & mask) | sbank);
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}
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}
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void WriteRegister(uint16_t addr, uint8_t value) override
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{
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if(addr < 0x8000) {
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switch(addr) {
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case 0x5000: _exRegs[0] = value; UpdateState(); break;
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case 0x5001: _exRegs[1] = value; UpdateState(); break;
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case 0x5007: _exRegs[2] = value; break;
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}
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} else {
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uint8_t lutValue = _lutAddr[_exRegs[2]][((addr >> 12) & 0x06) | (addr & 0x01)];
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addr = (lutValue & 0x01) | ((lutValue & 0x06) << 12) | 0x8000;
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if(lutValue == 0) {
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value = (value & 0xC0) | (_lutReg[_exRegs[2]][value & 0x07]);
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}
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MMC3::WriteRegister(addr, value);
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}
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}
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}; |