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Code Issues Projects Releases Wiki Activity

Simplify Z80 pn-handling a little

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This commit is contained in:
Adrian Conlon
2025-09-11 08:34:24 +01:00
parent 2bd50e5cd2
commit 3ca62c908c
1 changed files with 29 additions and 79 deletions
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108
Z80/Z80.cs
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@@ -483,10 +483,10 @@ namespace Z80
this.OnWritingMemory();
this.Tick(ticks);
this.LowerMREQ();
this.LowerWR();
this.Tick();
base.MemoryWrite();
this.RaiseWR();
this.LowerWR();
this.Tick();
base.MemoryWrite();
this.RaiseWR();
this.RaiseMREQ();
this.Tick();
this.OnWrittenMemory();
@@ -502,54 +502,25 @@ namespace Z80
Debug.Assert(this.M1.Lowered(), "M1 must be lowered to refresh memory");
this.Bus.Address.Assign(this.REFRESH, this.IV);
this.LowerRFSH();
this.Tick();
this.LowerMREQ();
this.RaiseMREQ();
this.Tick();
this.LowerMREQ();
this.RaiseMREQ();
this.RaiseRFSH();
}
private void SetMemoryRead()
{
this.LowerMREQ();
this.LowerRD();
}
private void ResetMemoryRead()
{
this.RaiseRD();
this.RaiseMREQ();
}
private void MemoryReadWithM1()
{
Debug.Assert(this.M1.Lowered());
this.Tick();
this.SetMemoryRead();
this.Tick();
_ = base.MemoryRead();
this.ResetMemoryRead();
this.RefreshMemory();
}
private void MemoryReadWithoutM1()
{
Debug.Assert(this.M1.Raised());
this.Tick();
this.SetMemoryRead();
this.Tick();
_ = base.MemoryRead();
this.ResetMemoryRead();
}
protected override byte MemoryRead()
{
this.OnReadingMemory();
this.Tick();
this.LowerMREQ();
this.LowerRD();
this.Tick();
_ = base.MemoryRead();
this.RaiseRD();
this.RaiseMREQ();
if (this.M1.Lowered())
{
this.MemoryReadWithM1();
}
else
{
this.MemoryReadWithoutM1();
this.RefreshMemory();
}
this.OnReadMemory();
this.Tick();
@@ -1626,7 +1597,7 @@ namespace Z80
this.IFF2 = this.IFF1;
this.IFF1 = false;
this.LowerM1();
_ = this.Bus.Data;
_ = this.Bus.Data;
this.RaiseM1();
this.Restart(0x66);
}
@@ -1652,7 +1623,7 @@ namespace Z80
protected override byte FetchInstruction()
{
this.LowerM1();
_ = base.FetchInstruction();
_ = base.FetchInstruction();
this.RaiseM1();
return this.Bus.Data;
}
@@ -2372,27 +2343,17 @@ namespace Z80
this.WritePort();
}
private void SetIOWrite()
{
this.LowerIORQ();
this.LowerWR();
}
private void ResetIOWrite()
{
this.RaiseWR();
this.RaiseIORQ();
}
private void WritePort()
{
this.MEMPTR.Assign(this.Bus.Address);
this.Tick();
this.Tick();
this.SetIOWrite();
this.Tick();
this.Ports.Write(this.Bus.Address, this.Bus.Data);
this.ResetIOWrite();
this.LowerIORQ();
this.LowerWR();
this.Tick();
this.Ports.Write(this.Bus.Address, this.Bus.Data);
this.RaiseWR();
this.RaiseIORQ();
this.Tick();
}
@@ -2409,27 +2370,16 @@ namespace Z80
this.ReadPort();
}
private void SetIORead()
{
this.LowerIORQ();
this.LowerRD();
}
private void ResetIORead()
{
this.RaiseRD();
this.RaiseIORQ();
}
private void ReadPort()
{
this.MEMPTR.Assign(this.Bus.Address);
this.Tick(2);
this.SetIORead();
this.Bus.Data = this.Ports.Read(this.Bus.Address);
this.Tick();
this.ResetIORead();
this.LowerIORQ();
this.LowerRD();
this.Bus.Data = this.Ports.Read(this.Bus.Address);
this.Tick();
this.RaiseRD();
this.RaiseIORQ();
this.Tick();
}