Example #1
0
        // The SuperGrafx has 32K of RAM and a different port configuration to allow
        // I/O access to VDC1, VDC2, and the VPC.
        byte ReadMemorySGX(int addr)
        {
            if (addr < 0xFFFFF) // read ROM
                return RomData[addr % RomLength];

            if (addr >= 0x1F0000 && addr < 0x1F8000) // read RAM
                return Ram[addr & 0x7FFF];

            if (addr >= 0x1FE000) // hardware page.
            {
                if (addr < 0x1FE400)
                {
                    addr &= 0x1F;
                    if (addr <= 0x07) return VDC1.ReadVDC(addr);
                    if (addr <= 0x0F) return VPC.ReadVPC(addr);
                    if (addr <= 0x17) return VDC2.ReadVDC(addr);
                    return 0xFF;
                }

                if (addr < 0x1FE800) { Cpu.PendingCycles--; return VCE.ReadVCE(addr); }
                if (addr < 0x1FEC00) return IOBuffer;
                if (addr < 0x1FF000) { IOBuffer = (byte)(Cpu.ReadTimerValue() | (IOBuffer & 0x80)); return IOBuffer; }
                if (addr >= 0x1FF000 &&
                    addr < 0x1FF400) { IOBuffer = ReadInput(); return IOBuffer; }
                if ((addr & ~1) == 0x1FF400) return IOBuffer;
                if (addr == 0x1FF402) { IOBuffer = Cpu.IRQControlByte; return IOBuffer; }
                if (addr == 0x1FF403) { IOBuffer = (byte)(Cpu.ReadIrqStatus() | (IOBuffer & 0xF8)); return IOBuffer; }
            }

            Log.Error("MEM", "UNHANDLED READ: {0:X6}", addr);
            return 0xFF;
        }
Example #2
0
        private byte ReadMemoryPopulous(int addr)
        {
            if (addr >= 0x80000 && addr < 0x88000)
            {
                return(PopulousRAM[addr & 0x7FFF]);
            }

            if (addr < 0xFFFFF)             // read ROM
            {
                return(RomData[addr % RomLength]);
            }

            if (addr >= 0x1F0000 && addr < 0x1F8000)             // read RAM
            {
                return(Ram[addr & 0x1FFF]);
            }

            if (addr >= 0x1FE000)             // hardware page.
            {
                if (addr < 0x1FE400)
                {
                    return(VDC1.ReadVDC(addr));
                }
                if (addr < 0x1FE800)
                {
                    Cpu.PendingCycles--; return(VCE.ReadVCE(addr));
                }
                if (addr < 0x1FEC00)
                {
                    return(IOBuffer);
                }
                if (addr < 0x1FF000)
                {
                    IOBuffer = (byte)(Cpu.ReadTimerValue() | (IOBuffer & 0x80)); return(IOBuffer);
                }
                if (addr >= 0x1FF000 &&
                    addr < 0x1FF400)
                {
                    IOBuffer = ReadInput(); return(IOBuffer);
                }
                if ((addr & ~1) == 0x1FF400)
                {
                    return(IOBuffer);
                }
                if (addr == 0x1FF402)
                {
                    IOBuffer = Cpu.IRQControlByte; return(IOBuffer);
                }
                if (addr == 0x1FF403)
                {
                    IOBuffer = (byte)(Cpu.ReadIrqStatus() | (IOBuffer & 0xF8)); return(IOBuffer);
                }
            }

            Log.Error("MEM", "UNHANDLED READ: {0:X6}", addr);
            return(0xFF);
        }
Example #3
0
        byte ReadMemory(int addr)
        {
            if (addr < 0xFFFFF)             // read ROM
            {
                return(RomData[addr % RomLength]);
            }

            if (addr >= 0x1F0000 && addr < 0x1F8000)             // read RAM
            {
                return(Ram[addr & 0x1FFF]);
            }

            if (addr >= 0x1FE000)             // hardware page.
            {
                if (addr < 0x1FE400)
                {
                    return(VDC1.ReadVDC(addr));
                }
                if (addr < 0x1FE800)
                {
                    Cpu.PendingCycles--; return(VCE.ReadVCE(addr));
                }
                if (addr < 0x1FEC00)
                {
                    return(IOBuffer);
                }
                if (addr < 0x1FF000)
                {
                    IOBuffer = (byte)(Cpu.ReadTimerValue() | (IOBuffer & 0x80)); return(IOBuffer);
                }
                if (addr >= 0x1FF000 &&
                    addr < 0x1FF400)
                {
                    IOBuffer = ReadInput(); return(IOBuffer);
                }
                if ((addr & ~1) == 0x1FF400)
                {
                    return(IOBuffer);
                }
                if (addr == 0x1FF402)
                {
                    IOBuffer = Cpu.IRQControlByte; return(IOBuffer);
                }
                if (addr == 0x1FF403)
                {
                    IOBuffer = (byte)(Cpu.ReadIrqStatus() | (IOBuffer & 0xF8)); return(IOBuffer);
                }
                if (addr >= 0x1FF800)
                {
                    return(ReadCD(addr));
                }
            }

            if (addr >= 0x1EE000 && addr <= 0x1EE7FF)               // BRAM
            {
                if (BramEnabled && BramLocked == false)
                {
                    return(BRAM[addr & 0x7FF]);
                }
                return(0xFF);
            }

            //CoreComm.MemoryCallbackSystem.CallRead((uint)addr);

            Log.Error("MEM", "UNHANDLED READ: {0:X6}", addr);
            return(0xFF);
        }
        byte ReadMemoryCD(int addr)
        {
            if (addr < 0x80000)             // read ROM
            {
                return(RomData[addr % RomLength]);
            }

            if (addr >= 0x1F0000 && addr < 0x1F8000)             // read RAM
            {
                return(Ram[addr & 0x1FFF]);
            }

            if (addr >= 0x100000 && addr < 0x110000)             // read CD RAM
            {
                return(CDRam[addr & 0xFFFF]);
            }

            if (addr >= 0xD0000 && addr < 0x100000 && SuperRam != null)             // Super SysCard RAM
            {
                return(SuperRam[addr - 0xD0000]);
            }

            if (addr >= 0x1FE000)             // hardware page.
            {
                if (addr < 0x1FE400)
                {
                    return(VDC1.ReadVDC(addr));
                }
                if (addr < 0x1FE800)
                {
                    Cpu.PendingCycles--; return(VCE.ReadVCE(addr));
                }
                if (addr < 0x1FEC00)
                {
                    return(IOBuffer);
                }
                if (addr < 0x1FF000)
                {
                    IOBuffer = (byte)(Cpu.ReadTimerValue() | (IOBuffer & 0x80)); return(IOBuffer);
                }
                if (addr >= 0x1FF000 &&
                    addr < 0x1FF400)
                {
                    IOBuffer = ReadInput(); return(IOBuffer);
                }
                if ((addr & ~1) == 0x1FF400)
                {
                    return(IOBuffer);
                }
                if (addr == 0x1FF402)
                {
                    IOBuffer = Cpu.IRQControlByte; return(IOBuffer);
                }
                if (addr == 0x1FF403)
                {
                    IOBuffer = (byte)(Cpu.ReadIrqStatus() | (IOBuffer & 0xF8)); return(IOBuffer);
                }
                if (addr >= 0x1FF800)
                {
                    return(ReadCD(addr));
                }
            }

            if (addr >= 0x80000 && addr < 0x88000 && ArcadeCard)
            {
                var  page  = ArcadePage[(addr >> 13) & 3];
                byte value = ArcadeRam[page.EffectiveAddress];
                page.Increment();
                return(value);
            }

            if (addr >= 0x1EE000 && addr <= 0x1EE7FF)               // BRAM
            {
                if (BramEnabled && BramLocked == false)
                {
                    return(BRAM[addr & 0x7FF]);
                }
                return(0xFF);
            }

            Log.Error("MEM", "UNHANDLED READ: {0:X6}", addr);
            return(0xFF);
        }