ZXHawk: start preparing 128k and +2a/+3 for updating timings
This commit is contained in:
Asnivor
parent
c80f873adf
commit
535534a94a
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@ -155,11 +155,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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return value;
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}
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/// <summary>
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/// Contends memory if necessary
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/// </summary>
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public abstract void ContendMemory(ushort addr);
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/// <summary>
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/// Checks whether supplied address is in a potentially contended bank
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/// </summary>
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@ -50,7 +50,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// This method is for 48k and 128k/+2 machines only and should be overridden for other models
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/// </summary>
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/// <param name="addr"></param>
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public abstract void ContendPort(ushort addr);
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//public abstract void ContendPort(ushort addr);
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}
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}
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@ -185,8 +185,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <returns></returns>
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public override byte ReadMemory(ushort addr)
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{
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ContendMemory(addr);
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var data = ReadBus(addr);
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return data;
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}
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@ -199,28 +197,9 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <param name="value"></param>
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public override void WriteMemory(ushort addr, byte value)
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{
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// update ULA screen buffer if necessary BEFORE T1 write
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if (((addr & 49152) == 16384 || ((addr & 0xc000) == 0xc000) && (RAMPaged == 5 || RAMPaged == 7)) && _render)
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ULADevice.RenderScreen((int)CurrentFrameCycle);
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ContendMemory(addr);
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WriteBus(addr, value);
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}
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/// <summary>
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/// Contends memory if necessary
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/// </summary>
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public override void ContendMemory(ushort addr)
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{
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/*
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if (IsContended(addr))
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{
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var delay = ULADevice.GetContentionValue((int)CurrentFrameCycle);
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CPU.TotalExecutedCycles += delay;
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}
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*/
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}
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/// <summary>
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/// Checks whether supplied address is in a potentially contended bank
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/// </summary>
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@ -18,9 +18,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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{
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bool deviceAddressed = true;
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// process IO contention
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ContendPort(port);
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int result = 0xFF;
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// check AY
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@ -53,29 +50,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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if (!deviceAddressed)
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{
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// If this is an unused port the floating memory bus should be returned
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// Floating bus is read on the previous cycle
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long _tStates = CurrentFrameCycle - 1;
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ULADevice.ReadFloatingBus((int)_tStates, ref result);
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/*
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// if we are on the top or bottom border return 0xff
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if ((_tStates < ULADevice.contentionStartPeriod) || (_tStates > ULADevice.contentionEndPeriod))
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{
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result = 0xff;
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}
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else
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{
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if (ULADevice.floatingBusTable[_tStates] < 0)
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{
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result = 0xff;
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}
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else
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{
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result = ReadBus((ushort)ULADevice.floatingBusTable[_tStates]);
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}
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}
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*/
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ULADevice.ReadFloatingBus((int)CurrentFrameCycle, ref result);
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}
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return (byte)result;
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@ -88,9 +63,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <param name="value"></param>
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public override void WritePort(ushort port, byte value)
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{
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// process IO contention
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ContendPort(port);
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// get a BitArray of the port
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BitArray portBits = new BitArray(BitConverter.GetBytes(port));
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// get a BitArray of the value byte
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@ -146,7 +118,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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{
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// store the last OUT byte
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LastULAOutByte = value;
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CPU.TotalExecutedCycles += ULADevice.GetContentionValue();
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/*
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Bit 7 6 5 4 3 2 1 0
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@ -156,9 +127,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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*/
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// Border - LSB 3 bits hold the border colour
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if (ULADevice.BorderColor != (value & BORDER_BIT))
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ULADevice.RenderScreen((int)CurrentFrameCycle);
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ULADevice.BorderColor = value & BORDER_BIT;
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// Buzzer
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@ -169,15 +137,5 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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//TapeDevice.ProcessMicBit((value & MIC_BIT) != 0);
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}
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}
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/// <summary>
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/// Contend port if necessary
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/// </summary>
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/// <param name="addr"></param>
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public override void ContendPort(ushort addr)
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{
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//CPUMon.ContendPort(addr);
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return;
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}
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}
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}
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@ -341,10 +341,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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break;
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}
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}
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// update ULA screen buffer if necessary
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if ((addr & 49152) == 16384 && _render)
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ULADevice.RenderScreen((int)CurrentFrameCycle);
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}
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/// <summary>
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@ -355,8 +351,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <returns></returns>
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public override byte ReadMemory(ushort addr)
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{
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ContendMemory(addr);
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var data = ReadBus(addr);
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return data;
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}
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@ -370,6 +364,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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public override void WriteMemory(ushort addr, byte value)
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{
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// update ULA screen buffer if necessary BEFORE T1 write
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/*
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if (!SpecialPagingMode)
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{
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if (((addr & 49152) == 16384 || ((addr & 0xc000) == 0xc000) && (RAMPaged == 5 || RAMPaged == 7)) && _render)
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@ -390,23 +385,8 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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break;
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}
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}
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ContendMemory(addr);
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WriteBus(addr, value);
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}
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/// <summary>
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/// Contends memory if necessary
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/// </summary>
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public override void ContendMemory(ushort addr)
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{
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/*
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if (IsContended(addr))
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{
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var delay = ULADevice.GetContentionValue((int)CurrentFrameCycle);
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CPU.TotalExecutedCycles += delay;
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}
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*/
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WriteBus(addr, value);
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}
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/// <summary>
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@ -18,9 +18,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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{
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bool deviceAddressed = true;
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// process IO contention
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ContendPort(port);
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int result = 0xFF;
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// check AY
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@ -53,102 +50,8 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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if (!deviceAddressed)
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{
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// If this is an unused port the floating memory bus should be returned
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// Floating bus is read on the previous cycle
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long _tStates = CurrentFrameCycle - 1;
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ULADevice.ReadFloatingBus((int)_tStates, ref result);
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/*
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// if we are on the top or bottom border return 0xff
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if ((_tStates < ULADevice.contentionStartPeriod) || (_tStates > ULADevice.contentionEndPeriod))
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{
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result = 0xff;
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}
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else
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{
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if (ULADevice.floatingBusTable[_tStates] < 0)
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{
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result = 0xff;
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}
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else
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{
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result = ReadBus((ushort)ULADevice.floatingBusTable[_tStates]);
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}
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}
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*/
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ULADevice.ReadFloatingBus((int)CurrentFrameCycle, ref result);
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}
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/*
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// Check whether the low bit is reset
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// Technically the ULA should respond to every even I/O address
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bool lowBitReset = (port & 0x0001) == 0;
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// Kempston joystick input takes priority over all other input
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// if this is detected just return the kempston byte
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if ((port & 0xe0) == 0 || (port & 0x20) == 0)
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{
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if (LocateUniqueJoystick(JoystickType.Kempston) != null)
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return (byte)((KempstonJoystick)LocateUniqueJoystick(JoystickType.Kempston) as KempstonJoystick).JoyLine;
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InputRead = true;
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}
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else if (lowBitReset)
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{
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// Even I/O address so get input from keyboard
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KeyboardDevice.ReadPort(port, ref result);
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TapeDevice.MonitorRead();
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// not a lagframe
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InputRead = true;
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// tape loading monitor cycle
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//TapeDevice.MonitorRead();
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// process tape INs
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TapeDevice.ReadPort(port, ref result);
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}
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else
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{
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// devices other than the ULA will respond here
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// (e.g. the AY sound chip in a 128k spectrum
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// AY register activate - on +3/2a both FFFD and BFFD active AY
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if ((port & 0xc002) == 0xc000)
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{
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result = (int)AYDevice.PortRead();
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}
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else if ((port & 0xc002) == 0x8000)
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{
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result = (int)AYDevice.PortRead();
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}
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// Kempston Mouse
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/*
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else if ((port & 0xF002) == 0x2000) //Is bit 12 set and bits 13,14,15 and 1 reset?
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{
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//result = udpDrive.DiskStatusRead();
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// disk drive is not yet implemented - return a max status byte for the menu to load
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result = 255;
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}
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else if ((port & 0xF002) == 0x3000)
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{
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//result = udpDrive.DiskReadByte();
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result = 0;
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}
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else if ((port & 0xF002) == 0x0)
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{
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if (PagingDisabled)
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result = 0x1;
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else
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result = 0xff;
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}
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*//*
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// if unused port the floating memory bus should be returned (still todo)
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}
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*/
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return (byte)result;
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}
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@ -160,9 +63,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <param name="value"></param>
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public override void WritePort(ushort port, byte value)
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{
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// process IO contention
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ContendPort(port);
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// get a BitArray of the port
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BitArray portBits = new BitArray(BitConverter.GetBytes(port));
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// get a BitArray of the value byte
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@ -244,9 +144,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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*/
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// Border - LSB 3 bits hold the border colour
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if (ULADevice.BorderColor != (value & BORDER_BIT))
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ULADevice.RenderScreen((int)CurrentFrameCycle);
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ULADevice.BorderColor = value & BORDER_BIT;
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// Buzzer
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@ -282,15 +179,5 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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}
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set { ROMPaged = value; }
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}
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/// <summary>
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/// Contend port if necessary
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/// </summary>
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/// <param name="addr"></param>
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public override void ContendPort(ushort addr)
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{
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//CPUMon.ContendPort(addr);
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return;
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}
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}
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}
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@ -341,10 +341,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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break;
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}
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}
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// update ULA screen buffer if necessary
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if ((addr & 49152) == 16384 && _render)
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ULADevice.RenderScreen((int)CurrentFrameCycle);
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}
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/// <summary>
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@ -355,8 +351,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <returns></returns>
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public override byte ReadMemory(ushort addr)
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{
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ContendMemory(addr);
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var data = ReadBus(addr);
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return data;
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}
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@ -369,6 +363,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <param name="value"></param>
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public override void WriteMemory(ushort addr, byte value)
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{
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/*
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// update ULA screen buffer if necessary BEFORE T1 write
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if (!SpecialPagingMode)
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{
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@ -390,23 +385,9 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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break;
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}
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}
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ContendMemory(addr);
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WriteBus(addr, value);
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}
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/// <summary>
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/// Contends memory if necessary
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/// </summary>
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public override void ContendMemory(ushort addr)
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{
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/*
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if (IsContended(addr))
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{
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var delay = ULADevice.GetContentionValue((int)CurrentFrameCycle);
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CPU.TotalExecutedCycles += delay;
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}
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*/
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WriteBus(addr, value);
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}
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/// <summary>
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@ -18,9 +18,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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{
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bool deviceAddressed = true;
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// process IO contention
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ContendPort(port);
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int result = 0xFF;
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// check AY
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@ -57,30 +54,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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if (!deviceAddressed)
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{
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// If this is an unused port the floating memory bus should be returned
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// Floating bus is read on the previous cycle
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long _tStates = CurrentFrameCycle - 1;
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ULADevice.ReadFloatingBus((int)_tStates, ref result);
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/*
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// if we are on the top or bottom border return 0xff
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if ((_tStates < ULADevice.contentionStartPeriod) || (_tStates > ULADevice.contentionEndPeriod))
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{
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result = 0xff;
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}
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else
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{
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if (ULADevice.floatingBusTable[_tStates] < 0)
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{
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result = 0xff;
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}
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else
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{
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result = ReadBus((ushort)ULADevice.floatingBusTable[_tStates]);
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}
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}
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*/
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ULADevice.ReadFloatingBus((int)CurrentFrameCycle, ref result);
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}
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return (byte)result;
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@ -93,9 +67,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <param name="value"></param>
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public override void WritePort(ushort port, byte value)
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{
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// process IO contention
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ContendPort(port);
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// get a BitArray of the port
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BitArray portBits = new BitArray(BitConverter.GetBytes(port));
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// get a BitArray of the value byte
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@ -179,9 +150,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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*/
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// Border - LSB 3 bits hold the border colour
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if (ULADevice.BorderColor != (value & BORDER_BIT))
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ULADevice.RenderScreen((int)CurrentFrameCycle);
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ULADevice.BorderColor = value & BORDER_BIT;
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// Buzzer
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@ -217,15 +185,5 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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}
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set { ROMPaged = value; }
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}
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/// <summary>
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/// Contend port if necessary
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/// </summary>
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/// <param name="addr"></param>
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public override void ContendPort(ushort addr)
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{
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//CPUMon.ContendPort(addr);
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return;
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}
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}
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}
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@ -96,7 +96,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <returns></returns>
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public override byte ReadMemory(ushort addr)
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{
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ContendMemory(addr);
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var data = ReadBus(addr);
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return data;
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}
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@ -108,41 +107,10 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
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/// <param name="addr"></param>
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/// <param name="value"></param>
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public override void WriteMemory(ushort addr, byte value)
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{
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||||
// update ULA screen buffer if necessary BEFORE T1 write
|
||||
//if ((addr & 49152) == 16384 && _render)
|
||||
//ULADevice.RenderScreen((int)CurrentFrameCycle);
|
||||
|
||||
ContendMemory(addr);
|
||||
{
|
||||
WriteBus(addr, value);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Contends memory if necessary
|
||||
/// </summary>
|
||||
public override void ContendMemory(ushort addr)
|
||||
{
|
||||
return;
|
||||
/*
|
||||
if (IsContended(addr))
|
||||
{
|
||||
var off = 1;
|
||||
var offset = CurrentFrameCycle + off;
|
||||
if (offset < 0)
|
||||
offset += ULADevice.FrameCycleLength;
|
||||
if (offset >= ULADevice.FrameCycleLength)
|
||||
offset -= ULADevice.FrameCycleLength;
|
||||
|
||||
var delay = ULADevice.GetContentionValue((int)offset);
|
||||
if (delay > 0)
|
||||
{
|
||||
|
||||
}
|
||||
CPU.TotalExecutedCycles += delay;
|
||||
}
|
||||
*/
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Checks whether supplied address is in a potentially contended bank
|
||||
/// </summary>
|
||||
|
|
|
|||
|
|
@ -15,9 +15,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
|
|||
/// <returns></returns>
|
||||
public override byte ReadPort(ushort port)
|
||||
{
|
||||
// process IO contention
|
||||
ContendPort(port);
|
||||
|
||||
int result = 0xFF;
|
||||
|
||||
// Check whether the low bit is reset
|
||||
|
|
@ -56,29 +53,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
|
|||
|
||||
|
||||
// If this is an unused port the floating memory bus should be returned
|
||||
ULADevice.ReadFloatingBus((int)CurrentFrameCycle, ref result);
|
||||
|
||||
/*
|
||||
// Floating bus is read on the previous cycle
|
||||
long _tStates = CurrentFrameCycle - 1;
|
||||
|
||||
// if we are on the top or bottom border return 0xff
|
||||
if ((_tStates < ULADevice.contentionStartPeriod) || (_tStates > ULADevice.contentionEndPeriod))
|
||||
{
|
||||
result = 0xff;
|
||||
}
|
||||
else
|
||||
{
|
||||
if (ULADevice.floatingBusTable[_tStates] < 0)
|
||||
{
|
||||
result = 0xff;
|
||||
}
|
||||
else
|
||||
{
|
||||
result = ReadBus((ushort)ULADevice.floatingBusTable[_tStates]);
|
||||
}
|
||||
}
|
||||
*/
|
||||
ULADevice.ReadFloatingBus((int)CurrentFrameCycle, ref result);
|
||||
}
|
||||
|
||||
return (byte)result;
|
||||
|
|
@ -91,9 +66,6 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
|
|||
/// <param name="value"></param>
|
||||
public override void WritePort(ushort port, byte value)
|
||||
{
|
||||
// process IO contention
|
||||
ContendPort(port);
|
||||
|
||||
// Check whether the low bit is reset
|
||||
// Technically the ULA should respond to every even I/O address
|
||||
if ((port & 0x0001) != 0)
|
||||
|
|
@ -124,39 +96,5 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
|
|||
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Simulates IO port contention based on the supplied address
|
||||
/// This method is for 48k and 128k/+2 machines only and should be overridden for other models
|
||||
/// </summary>
|
||||
/// <param name="addr"></param>
|
||||
public override void ContendPort(ushort addr)
|
||||
{
|
||||
/*
|
||||
It takes four T states for the Z80 to read a value from an I/O port, or write a value to a port. As is the case with memory access,
|
||||
this can be lengthened by the ULA. There are two effects which occur here:
|
||||
|
||||
If the port address being accessed has its low bit reset, the ULA is required to supply the result, which leads to a delay if it is
|
||||
currently busy handling the screen.
|
||||
The address of the port being accessed is placed on the data bus. If this is in the range 0x4000 to 0x7fff, the ULA treats this as an
|
||||
attempted access to contended memory and therefore introduces a delay. If the port being accessed is between 0xc000 and 0xffff,
|
||||
this effect does not apply, even on a 128K machine if a contended memory bank is paged into the range 0xc000 to 0xffff.
|
||||
|
||||
These two effects combine to lead to the following contention patterns:
|
||||
|
||||
High byte | |
|
||||
in 40 - 7F? | Low bit | Contention pattern
|
||||
------------+---------+-------------------
|
||||
No | Reset | N:1, C:3
|
||||
No | Set | N:4
|
||||
Yes | Reset | C:1, C:3
|
||||
Yes | Set | C:1, C:1, C:1, C:1
|
||||
|
||||
The 'Contention pattern' column should be interpreted from left to right. An "N:n" entry means that no delay is applied at this cycle, and the Z80 continues uninterrupted for 'n' T states. A "C:n" entry means that the ULA halts the Z80; the delay is exactly the same as would occur for a contended memory access at this cycle (eg 6 T states at cycle 14335, 5 at 14336, etc on the 48K machine). After this delay, the Z80 then continues for 'n' cycles.
|
||||
*/
|
||||
|
||||
//CPUMon.ContendPort(addr);
|
||||
return;
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue