BizHawk/BizHawk.Emulation.Cores/Computers/Commodore64/C64.MotherboardInterface.cs

140 lines
2.5 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace BizHawk.Emulation.Cores.Computers.Commodore64
{
sealed public partial class Motherboard
{
bool CassPort_ReadDataOutput()
{
return (cpu.PortData & 0x08) != 0;
}
bool CassPort_ReadMotor()
{
return (cpu.PortData & 0x20) != 0;
}
bool Cia0_ReadCnt()
{
return (userPort.ReadCounter1Buffer() && cia0.ReadCNTBuffer());
}
byte Cia0_ReadPortA()
{
return cia0InputLatchA;
}
byte Cia0_ReadPortB()
{
return cia0InputLatchB;
}
bool Cia0_ReadSP()
{
return (userPort.ReadSerial1Buffer() && cia0.ReadSPBuffer());
}
bool Cia1_ReadCnt()
{
return (userPort.ReadCounter2Buffer() && cia1.ReadCNTBuffer());
}
byte Cia1_ReadPortA()
{
// the low bits are actually the VIC memory address.
byte result = 0xFF;
if (serPort.WriteDataIn())
result &= 0x7F;
if (serPort.WriteClockIn())
result &= 0xBF;
return result;
}
bool Cia1_ReadSP()
{
return (userPort.ReadSerial2Buffer() && cia1.ReadSPBuffer());
}
byte Cpu_ReadPort()
{
byte data = 0x1F;
if (!cassPort.ReadSenseBuffer())
data &= 0xEF;
return data;
}
bool Glue_ReadIRQ()
{
return cia0.ReadIRQBuffer() & vic.ReadIRQBuffer() & cartPort.ReadIRQBuffer();
}
bool Pla_ReadCharen()
{
return (cpu.PortData & 0x04) != 0;
}
byte Pla_ReadCia0(int addr)
{
if (addr == 0xDC00 || addr == 0xDC01)
{
WriteInputPort();
inputRead = true;
}
return cia0.Read(addr);
}
byte Pla_ReadColorRam(int addr)
{
byte result = bus;
result &= 0xF0;
result |= colorRam.Read(addr);
return result;
}
bool Pla_ReadHiRam()
{
return (cpu.PortData & 0x02) != 0;
}
bool Pla_ReadLoRam()
{
return (cpu.PortData & 0x01) != 0;
}
bool SerPort_ReadAtnOut()
{
return (cia1.PortBData & 0x08) == 0;
}
bool SerPort_ReadClockOut()
{
return (cia1.PortAData & 0x10) == 0;
}
bool SerPort_ReadDataOut()
{
return (cia1.PortAData & 0x20) == 0;
}
byte Sid_ReadPotX()
{
return 0;
}
byte Sid_ReadPotY()
{
return 0;
}
byte Vic_ReadMemory(int addr)
{
// the system sees (cia1.PortAData & 0x3) but we use a shortcut
addr |= (0x3 - (((cia1.PortALatch & cia1.PortADirection) | (~cia1.PortADirection)) & 0x3)) << 14;
return pla.VicRead(addr);
}
}
}