diff --git a/src/emucore/Cart2K.cxx b/src/emucore/Cart2K.cxx
index a806f3b48..56c0ac632 100644
--- a/src/emucore/Cart2K.cxx
+++ b/src/emucore/Cart2K.cxx
@@ -32,7 +32,7 @@ Cartridge2K::Cartridge2K(const ByteBuffer& image, size_t size,
     mySize <<= 1;
 
   // We can't use a size smaller than the minimum page size in Stella
-  mySize = std::max<uInt32>(mySize, System::PAGE_SIZE);
+  mySize = std::max<size_t>(mySize, System::PAGE_SIZE);
 
   // Initialize ROM with illegal 6502 opcode that causes a real 6502 to jam
   myImage = make_unique<uInt8[]>(mySize);
@@ -44,7 +44,7 @@ Cartridge2K::Cartridge2K(const ByteBuffer& image, size_t size,
 
   // Set mask for accessing the image buffer
   // This is guaranteed to work, as mySize is a power of two
-  myMask = mySize - 1;
+  myMask = static_cast<uInt16>(mySize) - 1;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/src/emucore/Cart2K.hxx b/src/emucore/Cart2K.hxx
index fd636e0cf..e3fc8834a 100644
--- a/src/emucore/Cart2K.hxx
+++ b/src/emucore/Cart2K.hxx
@@ -130,10 +130,10 @@ class Cartridge2K : public Cartridge
     ByteBuffer myImage;
 
     // Size of the ROM image
-    uInt32 mySize;
+    size_t mySize;
 
     // Mask to use for mirroring
-    uInt32 myMask;
+    uInt16 myMask;
 
   private:
     // Following constructors and assignment operators not supported
diff --git a/src/emucore/Cart4K.cxx b/src/emucore/Cart4K.cxx
index 89196c993..1c1ee885f 100644
--- a/src/emucore/Cart4K.cxx
+++ b/src/emucore/Cart4K.cxx
@@ -64,15 +64,3 @@ const uInt8* Cartridge4K::getImage(size_t& size) const
   size = myImage.size();
   return myImage.data();
 }
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-bool Cartridge4K::save(Serializer&) const
-{
-  return true;
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-bool Cartridge4K::load(Serializer&)
-{
-  return true;
-}
diff --git a/src/emucore/Cart4K.hxx b/src/emucore/Cart4K.hxx
index 2cd5f6adb..5285dba35 100644
--- a/src/emucore/Cart4K.hxx
+++ b/src/emucore/Cart4K.hxx
@@ -86,7 +86,7 @@ class Cartridge4K : public Cartridge
       @param out  The Serializer object to use
       @return  False on any errors, else true
     */
-    bool save(Serializer& out) const override;
+    bool save(Serializer& out) const override { return true; }
 
     /**
       Load the current state of this cart from the given Serializer.
@@ -94,7 +94,7 @@ class Cartridge4K : public Cartridge
       @param in  The Serializer object to use
       @return  False on any errors, else true
     */
-    bool load(Serializer& in) override;
+    bool load(Serializer& in) override { return true; }
 
     /**
       Get a descriptor for the device name (used in error checking).
diff --git a/src/emucore/CartAR.cxx b/src/emucore/CartAR.cxx
index a8f84fa1e..094b2420f 100644
--- a/src/emucore/CartAR.cxx
+++ b/src/emucore/CartAR.cxx
@@ -316,7 +316,7 @@ void CartridgeAR::initializeROM()
   ourDummyROMCode[281] = mySystem->randGenerator().next();
 
   // Initialize ROM with illegal 6502 opcode that causes a real 6502 to jam
-  std::fill_n(myImage.begin() + (3<<11), 2048, 0x02);
+  std::fill_n(myImage.begin() + (3<<11), 2_KB, 0x02);
 
   // Copy the "dummy" Supercharger BIOS code into the ROM area
   std::copy_n(ourDummyROMCode.data(), ourDummyROMCode.size(), myImage.data() + (3<<11));
diff --git a/src/emucore/CartBUS.cxx b/src/emucore/CartBUS.cxx
index f916f5cef..09572f083 100644
--- a/src/emucore/CartBUS.cxx
+++ b/src/emucore/CartBUS.cxx
@@ -98,7 +98,7 @@ void CartridgeBUS::reset()
 void CartridgeBUS::setInitialState()
 {
   // Copy initial BUS driver to Harmony RAM
-  std::copy_n(myImage.begin(), 0x0800, myBusDriverImage);
+  std::copy_n(myImage.begin(), 2_KB, myBusDriverImage);
 
   myMusicWaveformSize.fill(27);
 
diff --git a/src/emucore/CartCDF.cxx b/src/emucore/CartCDF.cxx
index d1a79a16d..a3b8d92f1 100644
--- a/src/emucore/CartCDF.cxx
+++ b/src/emucore/CartCDF.cxx
@@ -68,11 +68,11 @@ CartridgeCDF::CartridgeCDF(const ByteBuffer& image, size_t size,
   std::copy_n(image.get(), std::min(myImage.size(), size), myImage.begin());
 
   // even though the ROM is 32K, only 28K is accessible to the 6507
-  createCodeAccessBase(4096 * 7);
+  createCodeAccessBase(28_KB);
 
   // Pointer to the program ROM (28K @ 0 byte offset)
   // which starts after the 2K CDF Driver and 2K C Code
-  myProgramImage = myImage.data() + 4096;
+  myProgramImage = myImage.data() + 4_KB;
 
   // Pointer to CDF driver in RAM
   myBusDriverImage = myCDFRAM.data();
@@ -96,7 +96,7 @@ CartridgeCDF::CartridgeCDF(const ByteBuffer& image, size_t size,
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void CartridgeCDF::reset()
 {
-  initializeRAM(myCDFRAM.data()+2048, myCDFRAM.size()-2048);
+  initializeRAM(myCDFRAM.data()+2_KB, myCDFRAM.size()-2_KB);
 
   // CDF always starts in bank 6
   initializeStartBank(6);
@@ -114,7 +114,7 @@ void CartridgeCDF::reset()
 void CartridgeCDF::setInitialState()
 {
   // Copy initial CDF driver to Harmony RAM
-  std::copy_n(myImage.begin(), 0x0800, myBusDriverImage);
+  std::copy_n(myImage.begin(), 2_KB, myBusDriverImage);
 
   myMusicWaveformSize.fill(27);
 
diff --git a/src/emucore/CartCDF.hxx b/src/emucore/CartCDF.hxx
index 81c41c7f8..7c1e6aad4 100644
--- a/src/emucore/CartCDF.hxx
+++ b/src/emucore/CartCDF.hxx
@@ -20,8 +20,6 @@
 
 class System;
 class Thumbulator;
-class CartridgeCDFWidget;
-class CartridgeCDFInfoWidget;
 
 #include "bspf.hxx"
 #include "Cart.hxx"
@@ -41,8 +39,8 @@ class CartridgeCDFInfoWidget;
 */
 class CartridgeCDF : public Cartridge
 {
-  friend CartridgeCDFWidget;
-  friend CartridgeCDFInfoWidget;
+  friend class CartridgeCDFWidget;
+  friend class CartridgeCDFInfoWidget;
   friend class CartridgeRamCDFWidget;
 
   public:
diff --git a/src/emucore/CartCV.hxx b/src/emucore/CartCV.hxx
index 9a614c01b..d0df0115f 100644
--- a/src/emucore/CartCV.hxx
+++ b/src/emucore/CartCV.hxx
@@ -137,16 +137,16 @@ class CartridgeCV : public Cartridge
 
   private:
     // The 2k ROM image for the cartridge
-    std::array<uInt8, 0x0800> myImage;
+    std::array<uInt8, 2_KB> myImage;
 
     // Initial size of the cart data
     size_t mySize;
 
     // The 1024 bytes of RAM
-    std::array<uInt8, 0x0400> myRAM;
+    std::array<uInt8, 1_KB> myRAM;
 
     // Initial RAM data from the cart (doesn't always exist)
-    std::array<uInt8, 0x0400> myInitialRAM;
+    std::array<uInt8, 1_KB> myInitialRAM;
 
   private:
     // Following constructors and assignment operators not supported
diff --git a/src/emucore/CartDPC.cxx b/src/emucore/CartDPC.cxx
index f129c7a23..e25ecf093 100644
--- a/src/emucore/CartDPC.cxx
+++ b/src/emucore/CartDPC.cxx
@@ -30,13 +30,13 @@ CartridgeDPC::CartridgeDPC(const ByteBuffer& image, size_t size,
 {
   // Make a copy of the entire image
   std::copy_n(image.get(), std::min(myImage.size(), size), myImage.begin());
-  createCodeAccessBase(8192);
+  createCodeAccessBase(8_KB);
 
   // Pointer to the program ROM (8K @ 0 byte offset)
   myProgramImage = myImage.data();
 
   // Pointer to the display ROM (2K @ 8K offset)
-  myDisplayImage = myProgramImage + 8192;
+  myDisplayImage = myProgramImage + 8_KB;
 
   // Initialize the DPC data fetcher registers
   myTops.fill(0);
diff --git a/src/emucore/CartDPCPlus.cxx b/src/emucore/CartDPCPlus.cxx
index 75aa3dd12..3badc9fba 100644
--- a/src/emucore/CartDPCPlus.cxx
+++ b/src/emucore/CartDPCPlus.cxx
@@ -44,16 +44,16 @@ CartridgeDPCPlus::CartridgeDPCPlus(const ByteBuffer& image, size_t size,
   if(mySize < myImage.size())
     myImage.fill(0);
   std::copy_n(image.get(), size, myImage.begin() + (myImage.size() - mySize));
-  createCodeAccessBase(4_KB * 6);
+  createCodeAccessBase(24_KB);
 
-  // Pointer to the program ROM (24K @ 3072 byte offset; ignore first 3K)
-  myProgramImage = myImage.data() + 0xC00;
+  // Pointer to the program ROM (24K @ 3K offset; ignore first 3K)
+  myProgramImage = myImage.data() + 3_KB;
 
   // Pointer to the display RAM
-  myDisplayImage = myDPCRAM.data() + 0xC00;
+  myDisplayImage = myDPCRAM.data() + 3_KB;
 
   // Pointer to the Frequency RAM
-  myFrequencyImage = myDisplayImage + 0x1000;
+  myFrequencyImage = myDisplayImage + 4_KB;
 
   // Create Thumbulator ARM emulator
   bool devSettings = settings.getBool("dev.settings");
@@ -67,7 +67,7 @@ CartridgeDPCPlus::CartridgeDPCPlus(const ByteBuffer& image, size_t size,
 
   // Currently only one known DPC+ ARM driver exhibits a problem
   // with the default mask to use for DFxFRACLOW
-  if(MD5::hash(image, 3*1024) == "8dd73b44fd11c488326ce507cbeb19d1")
+  if(MD5::hash(image, 3_KB) == "8dd73b44fd11c488326ce507cbeb19d1")
     myFractionalLowMask = 0x0F0000;
 
   setInitialState();
@@ -92,7 +92,7 @@ void CartridgeDPCPlus::setInitialState()
   myDPCRAM.fill(0);
 
   // Copy initial DPC display data and Frequency table state to Harmony RAM
-  std::copy_n(myProgramImage + 0x6000, 0x1400, myDisplayImage);
+  std::copy_n(myProgramImage + 24_KB, 5_KB, myDisplayImage);
 
   // Initialize the DPC data fetcher registers
   myTops.fill(0);
diff --git a/src/emucore/CartDetector.cxx b/src/emucore/CartDetector.cxx
index b6c52a339..957178419 100644
--- a/src/emucore/CartDetector.cxx
+++ b/src/emucore/CartDetector.cxx
@@ -402,7 +402,7 @@ Bankswitch::Type CartDetector::autodetectType(const ByteBuffer& image, size_t si
   {
     type = Bankswitch::Type::_WD;
   }
-  else if(size >= 10240 && size <= 10496)  // ~10K - Pitfall2
+  else if(size >= 10_KB && size <= 10_KB + 256)  // ~10K - Pitfall2
   {
     type = Bankswitch::Type::_DPC;
   }
@@ -915,7 +915,7 @@ bool CartDetector::isProbablyFA2(const ByteBuffer& image, size_t)
   // file sizes
 
   // 32K version has all zeros in 29K-32K area
-  for(uInt32 i = 29*1024; i < 32*1024; ++i)
+  for(uInt32 i = 29_KB; i < 32_KB; ++i)
     if(image[i] != 0)
       return false;
 
diff --git a/src/emucore/Control.hxx b/src/emucore/Control.hxx
index 0a61a2fff..54442928c 100644
--- a/src/emucore/Control.hxx
+++ b/src/emucore/Control.hxx
@@ -327,10 +327,10 @@ class Controller : public Serializable
 
   private:
     /// The boolean value on each digital pin
-    bool myDigitalPinState[5];
+    std::array<bool, 5> myDigitalPinState;
 
     /// The analog value on each analog pin
-    Int32 myAnalogPinValue[2];
+    std::array<Int32, 2> myAnalogPinValue;
 
   private:
     // Following constructors and assignment operators not supported
diff --git a/src/emucore/M6532.cxx b/src/emucore/M6532.cxx
index d9bc051a5..b58a9f15c 100644
--- a/src/emucore/M6532.cxx
+++ b/src/emucore/M6532.cxx
@@ -75,7 +75,7 @@ void M6532::reset()
   myDDRA = myDDRB = myOutA = myOutB = 0x00;
 
   // Zero the timer registers
-  myOutTimer[0] = myOutTimer[1] = myOutTimer[2] = myOutTimer[3] = 0x00;
+  myOutTimer.fill(0x00);
 
   // Zero the interrupt flag register and mark D7 as invalid
   myInterruptFlag = 0x00;
@@ -383,7 +383,7 @@ bool M6532::save(Serializer& out) const
 
     out.putByte(myInterruptFlag);
     out.putBool(myEdgeDetectPositive);
-    out.putByteArray(myOutTimer, 4);
+    out.putByteArray(myOutTimer.data(), myOutTimer.size());
   }
   catch(...)
   {
@@ -416,7 +416,7 @@ bool M6532::load(Serializer& in)
 
     myInterruptFlag = in.getByte();
     myEdgeDetectPositive = in.getBool();
-    in.getByteArray(myOutTimer, 4);
+    in.getByteArray(myOutTimer.data(), myOutTimer.size());
   }
   catch(...)
   {
diff --git a/src/emucore/M6532.hxx b/src/emucore/M6532.hxx
index 2eed285e4..569dfda77 100644
--- a/src/emucore/M6532.hxx
+++ b/src/emucore/M6532.hxx
@@ -210,7 +210,7 @@ class M6532 : public Device
     bool myEdgeDetectPositive;
 
     // Last value written to the timer registers
-    uInt8 myOutTimer[4];
+    std::array<uInt8, 4> myOutTimer;
 
     // Accessible bits in the interrupt flag register
     // All other bits are always zeroed
diff --git a/src/emucore/MT24LC256.hxx b/src/emucore/MT24LC256.hxx
index 2a2009764..8555f53a5 100644
--- a/src/emucore/MT24LC256.hxx
+++ b/src/emucore/MT24LC256.hxx
@@ -46,7 +46,7 @@ class MT24LC256
 
   private:
     // Sizes of the EEPROM
-    static constexpr uInt32 FLASH_SIZE = 32 * 1024;
+    static constexpr uInt32 FLASH_SIZE = 32_KB;
 
   public:
     static constexpr uInt32 PAGE_SIZE = 64;
diff --git a/src/emucore/System.cxx b/src/emucore/System.cxx
index ce4151627..46e238d9e 100644
--- a/src/emucore/System.cxx
+++ b/src/emucore/System.cxx
@@ -41,11 +41,8 @@ System::System(Random& random, M6502& m6502, M6532& m6532,
 {
   // Initialize page access table
   PageAccess access(&myNullDevice, System::PageAccessType::READ);
-  for(int page = 0; page < NUM_PAGES; ++page)
-  {
-    myPageAccessTable[page] = access;
-    myPageIsDirtyTable[page] = false;
-  }
+  myPageAccessTable.fill(access);
+  myPageIsDirtyTable.fill(false);
 
   // Bus starts out unlocked (in other words, peek() changes myDataBusState)
   myDataBusLocked = false;
@@ -102,8 +99,7 @@ bool System::isPageDirty(uInt16 start_addr, uInt16 end_addr) const
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void System::clearDirtyPages()
 {
-  for(uInt32 i = 0; i < NUM_PAGES; ++i)
-    myPageIsDirtyTable[i] = false;
+  myPageIsDirtyTable.fill(false);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/src/emucore/System.hxx b/src/emucore/System.hxx
index 074af0f44..63c314385 100644
--- a/src/emucore/System.hxx
+++ b/src/emucore/System.hxx
@@ -399,10 +399,10 @@ class System : public Serializable
     NullDevice myNullDevice;
 
     // The list of PageAccess structures
-    PageAccess myPageAccessTable[NUM_PAGES];
+    std::array<PageAccess, NUM_PAGES> myPageAccessTable;
 
     // The list of dirty pages
-    bool myPageIsDirtyTable[NUM_PAGES];
+    std::array<bool, NUM_PAGES> myPageIsDirtyTable;
 
     // The current state of the Data Bus
     uInt8 myDataBusState;
diff --git a/src/emucore/tia/TIA.hxx b/src/emucore/tia/TIA.hxx
index aab7a483e..dcf467ebe 100644
--- a/src/emucore/tia/TIA.hxx
+++ b/src/emucore/tia/TIA.hxx
@@ -734,7 +734,7 @@ class TIA : public Device
     /**
      * The paddle readout circuits.
      */
-    PaddleReader myPaddleReaders[4];
+    std::array<PaddleReader, 4> myPaddleReaders;
 
     /**
      * Circuits for the "latched inputs".