Add cpu reset.

src/cpu/ctfe_d6502.d

@@ -495,7 +495,7 @@ string Nop(int mode)
     if (mode == IMP ||  mode == NP1 || mode == NP8)
         return "";
     else
-        return PreAccess() ~
+        return Tick() ~
                ReadRaw("address") ~ ";\n";
 }
 
@@ -1013,7 +1013,7 @@ string CheckShortcut(string base, string addr, string chip, int exCyc)
 
 string ReadInto(string var, string action, string addr)
 {
-    return PreAccess() ~
+    return Tick() ~
            var ~ " " ~ action ~ " " ~ ReadRaw("(" ~ addr ~ ")") ~ ";\n";
 }
 
@@ -1074,27 +1074,27 @@ string ReadWordOp(string var)
     return ReadWordOp("", var);
 }
 
-string PreAccess()
+string Tick()
 {
     return If!(cumulative)("++cycles;\n", Attr("clock") ~ ".tick();\n");
 }
 
 string Peek(string addr)
 {
-    return PreAccess() ~
+    return Tick() ~
            If!(strict)(Attr("memory") ~ ".read(" ~ addr ~");\n");
 }
 
 string Poke(string addr, string val)
 {
-    return PreAccess() ~
+    return Tick() ~
            If!(strict)(
                Attr("memory") ~ ".write(" ~ addr ~ ", " ~ val ~ ");\n");
 }
 
 string Write(string addr, string val)
 {
-    return PreAccess() ~
+    return Tick() ~
            Attr("memory") ~ ".write(" ~ addr ~ ", " ~ val ~ ");\n";
 }
 
@@ -1118,7 +1118,7 @@ string PullStatus()
 {
     return Peek(STACK) ~
            IncSP() ~
-           PreAccess() ~
+           Tick() ~
            Attr("statusFromByte") ~ "(" ~
            ReadRaw(STACK) ~ ");\n";
 }
@@ -1151,13 +1151,13 @@ string PullPC()
 
 string LoadLoByte(string type, string var, string addr)
 {
-    return PreAccess() ~
+    return Tick() ~
            Local(type, var) ~ " = " ~ ReadRaw(addr) ~ ";\n";
 }
 
 string LoadHiByte(string var, string addr)
 {
-    return PreAccess() ~
+    return Tick() ~
            var ~ " |= (" ~ ReadRaw(addr) ~ " << 8);\n";
 }
 

src/cpu/d6502.d

@@ -102,6 +102,8 @@ if (__traits(compiles, {
     }
 
     bool keepRunning;
+    bool signalActive;
+    bool resetLow;
 
     final void run(bool continuous)
     {
@@ -115,25 +117,42 @@ if (__traits(compiles, {
         }
         do
         {
-            version(Cumulative)
-            {
-                static if (!opArray) cycles = 1;
-            }
-            else
-            {
-                clock.tick();
-            }
-            // XXX check signals, NMI/IRQ delays, etc.
+            version(Cumulative) { static if (!opArray) cycles = 1; }
+            else { clock.tick(); }
+            if (signalActive) handleSignals();
             opcode = memory.read(PC++);
             mixin(OpExecute(_chip));
         } while (keepRunning);
     }
 
+    // TODO: irq/nmi
+    void handleSignals()
+    {
+        if (resetLow) doReset();
+        // XXX fix when more than one signal
+        signalActive = resetLow;
+    }
+
+    void doReset()
+    {
+        mixin(Tick() ~ Tick() ~
+              Peek(STACK) ~ DecSP() ~
+              Peek(STACK) ~ DecSP() ~
+              Peek(STACK) ~ DecSP());
+
+        I = true;
+        resetLow = false;
+
+        mixin(ReadWord(_PC, "RESET_VECTOR") ~
+              Done());
+    }
+
     version(OpDelegates) mixin (OpMethods(_chip));
 }
 
 
 enum ushort IRQ_VECTOR = 0xFFFE;
+enum ushort RESET_VECTOR = 0xFFFC;
 
 
 //alias Cpu!("6502", false, false) T1;