In the case of 'read from write port', make sure RAM is modified before exception is thrown.

src/emucore/Cart3E.cxx

@@ -91,8 +91,9 @@ uInt8 Cartridge3E::peek(uInt16 address)
           return value;
         else
         {
+          myRAM[(address & 0x03FF) + ((myCurrentBank - 256) << 10)] = value;
           triggerReadFromWritePort(peekAddress);
-          return myRAM[(address & 0x03FF) + ((myCurrentBank - 256) << 10)] = value;
+          return value;
         }
       }
     }

src/emucore/Cart3EPlus.cxx

@@ -103,12 +103,12 @@ uInt8 Cartridge3EPlus::peek(uInt16 address)
       return value;
     else
     {
-      triggerReadFromWritePort(peekAddress);
-
       Int32 ramBank = imageBank & BIT_BANK_MASK;    // discard irrelevant bits
       Int32 offset = ramBank << RAM_BANK_TO_POWER;  // base bank address in RAM
       offset += (address & BITMASK_RAM_BANK);       // + byte offset in RAM bank
-      return myRAM[offset] = value;
+      myRAM[offset] = value;
+      triggerReadFromWritePort(peekAddress);
+      return value;
     }
   }
 

src/emucore/Cart4KSC.cxx

@@ -75,7 +75,7 @@ void Cartridge4KSC::install(System& system)
 uInt8 Cartridge4KSC::peek(uInt16 address)
 {
   // The only way we can get to this method is if we attempt to read from
-  // the write port (0xF000 - 0xF080, 128 bytes), in which case an
+  // the write port (0xF000 - 0xF07F, 128 bytes), in which case an
   // unwanted write is triggered
   uInt8 value = mySystem->getDataBusState(0xFF);
 
@@ -83,8 +83,9 @@ uInt8 Cartridge4KSC::peek(uInt16 address)
     return value;
   else
   {
+    myRAM[address & 0x0FFF] = value;
     triggerReadFromWritePort(address);
-    return myRAM[address & 0x0FFF] = value;
+    return value;
   }
 }
 

src/emucore/CartBFSC.cxx

@@ -79,7 +79,7 @@ uInt8 CartridgeBFSC::peek(uInt16 address)
   if((address >= 0x0F80) && (address <= 0x0FBF))
     bank(address - 0x0F80);
 
-  if(address < 0x0080)  // Write port is at 0xF000 - 0xF080 (128 bytes)
+  if(address < 0x0080)  // Write port is at 0xF000 - 0xF07F (128 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -88,8 +88,9 @@ uInt8 CartridgeBFSC::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartCTY.cxx

@@ -131,8 +131,9 @@ uInt8 CartridgeCTY::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else if(address < 0x0080)  // Read port is at $1040 - $107F (64 bytes)

src/emucore/CartCV.cxx

@@ -98,7 +98,7 @@ void CartridgeCV::install(System& system)
 uInt8 CartridgeCV::peek(uInt16 address)
 {
   // The only way we can get to this method is if we attempt to read from
-  // the write port (0xF400 - 0xF800, 1024 bytes), in which case an
+  // the write port (0xF400 - 0xF7FF, 1024 bytes), in which case an
   // unwanted write is triggered
   uInt8 value = mySystem->getDataBusState(0xFF);
 
@@ -106,8 +106,9 @@ uInt8 CartridgeCV::peek(uInt16 address)
     return value;
   else
   {
+    myRAM[address & 0x03FF] = value;
     triggerReadFromWritePort(address);
-    return myRAM[address & 0x03FF] = value;
+    return value;
   }
 }
 

src/emucore/CartCVPlus.cxx

@@ -83,7 +83,7 @@ void CartridgeCVPlus::install(System& system)
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 uInt8 CartridgeCVPlus::peek(uInt16 address)
 {
-  if((address & 0x0FFF) < 0x0800)  // Write port is at 0xF400 - 0xF800 (1024 bytes)
+  if((address & 0x0FFF) < 0x0800)  // Write port is at 0xF400 - 0xF7FF (1024 bytes)
   {                                // Read port is handled in ::install()
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -92,8 +92,9 @@ uInt8 CartridgeCVPlus::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address & 0x03FF] = value;
       triggerReadFromWritePort(address);
-      return myRAM[address & 0x03FF] = value;
+      return value;
     }
   }
   else

src/emucore/CartDASH.cxx

@@ -107,12 +107,12 @@ uInt8 CartridgeDASH::peek(uInt16 address)
       return value;
     else
     {
-      triggerReadFromWritePort(peekAddress);
-
       Int32 ramBank = imageBank & BIT_BANK_MASK;    // discard irrelevant bits
       Int32 offset = ramBank << RAM_BANK_TO_POWER;  // base bank address in RAM
       offset += (address & BITMASK_RAM_BANK);       // + byte offset in RAM bank
-      return myRAM[offset] = value;
+      myRAM[offset] = value;
+      triggerReadFromWritePort(peekAddress);
+      return value;
     }
   }
 

src/emucore/CartDFSC.cxx

@@ -79,7 +79,7 @@ uInt8 CartridgeDFSC::peek(uInt16 address)
   if((address >= 0x0FC0) && (address <= 0x0FDF))
     bank(address - 0x0FC0);
 
-  if(address < 0x0080)  // Write port is at 0xF000 - 0xF080 (128 bytes)
+  if(address < 0x0080)  // Write port is at 0xF000 - 0xF07F (128 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -88,8 +88,9 @@ uInt8 CartridgeDFSC::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartEFSC.cxx

@@ -79,7 +79,7 @@ uInt8 CartridgeEFSC::peek(uInt16 address)
   if((address >= 0x0FE0) && (address <= 0x0FEF))
     bank(address - 0x0FE0);
 
-  if(address < 0x0080)  // Write port is at 0xF000 - 0xF080 (128 bytes)
+  if(address < 0x0080)  // Write port is at 0xF000 - 0xF07F (128 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -88,8 +88,9 @@ uInt8 CartridgeEFSC::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartF4SC.cxx

@@ -79,7 +79,7 @@ uInt8 CartridgeF4SC::peek(uInt16 address)
   if((address >= 0x0FF4) && (address <= 0x0FFB))
     bank(address - 0x0FF4);
 
-  if(address < 0x0080)  // Write port is at 0xF000 - 0xF080 (128 bytes)
+  if(address < 0x0080)  // Write port is at 0xF000 - 0xF07F (128 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -88,8 +88,9 @@ uInt8 CartridgeF4SC::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
 

src/emucore/CartF6SC.cxx

@@ -102,7 +102,7 @@ uInt8 CartridgeF6SC::peek(uInt16 address)
       break;
   }
 
-  if(address < 0x0080)  // Write port is at 0xF000 - 0xF080 (128 bytes)
+  if(address < 0x0080)  // Write port is at 0xF000 - 0xF07F (128 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -111,8 +111,9 @@ uInt8 CartridgeF6SC::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartF8SC.cxx

@@ -92,7 +92,7 @@ uInt8 CartridgeF8SC::peek(uInt16 address)
       break;
   }
 
-  if(address < 0x0080)  // Write port is at 0xF000 - 0xF080 (128 bytes)
+  if(address < 0x0080)  // Write port is at 0xF000 - 0xF07F (128 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -101,8 +101,9 @@ uInt8 CartridgeF8SC::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartFA.cxx

@@ -97,7 +97,7 @@ uInt8 CartridgeFA::peek(uInt16 address)
       break;
   }
 
-  if(address < 0x0100)  // Write port is at 0xF000 - 0xF100 (256 bytes)
+  if(address < 0x0100)  // Write port is at 0xF000 - 0xF0FF (256 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -106,8 +106,9 @@ uInt8 CartridgeFA::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartFA2.cxx

@@ -136,7 +136,7 @@ uInt8 CartridgeFA2::peek(uInt16 address)
       break;
   }
 
-  if(address < 0x0100)  // Write port is at 0xF000 - 0xF100 (256 bytes)
+  if(address < 0x0100)  // Write port is at 0xF000 - 0xF0FF (256 bytes)
   {
     // Reading from the write port triggers an unwanted write
     uInt8 value = mySystem->getDataBusState(0xFF);
@@ -145,8 +145,9 @@ uInt8 CartridgeFA2::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address] = value;
+      return value;
     }
   }
   else

src/emucore/CartMNetwork.cxx

@@ -123,8 +123,9 @@ uInt8 CartridgeMNetwork::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[address & (BANK_SIZE / 2 - 1)] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[address & (BANK_SIZE / 2 - 1)] = value;
+      return value;
     }
   }
   else if((address >= 0x0800) && (address <= 0x08FF))
@@ -136,8 +137,9 @@ uInt8 CartridgeMNetwork::peek(uInt16 address)
       return value;
     else
     {
+      myRAM[1024 + (myCurrentRAM << 8) + (address & 0x00FF)] = value;
       triggerReadFromWritePort(peekAddress);
-      return myRAM[1024 + (myCurrentRAM << 8) + (address & 0x00FF)] = value;
+      return value;
     }
   }
   else

src/emucore/CartWD.cxx

@@ -117,8 +117,9 @@ uInt8 CartridgeWD::peek(uInt16 address)
         return value;
       else
       {
+        myRAM[address & 0x003F] = value;
         triggerReadFromWritePort(peekAddress);
-        return myRAM[address & 0x003F] = value;
+        return value;
       }
     }
     else if(address < 0x0400)