Try to remove some casting warnings by redefining ROM size types.

src/InputOutput.cpp

@@ -6,7 +6,7 @@
 
 #include "../inc/Register.h"
 
-size_t EightBit::InputOutput::size() const noexcept {
+uint16_t EightBit::InputOutput::size() const noexcept {
 	return 0x100;
 }
 

src/Rom.cpp

@@ -57,8 +57,10 @@ EightBit::Rom& EightBit::Rom::operator=(const Rom& rhs) {
 	return *this;
 }
 
-size_t EightBit::Rom::size() const noexcept {
-	return m_bytes.size();
+uint16_t EightBit::Rom::size() const noexcept {
+	const auto size = BYTES().size();
+	assert(size <= 0x10000);
+	return static_cast<uint16_t>(size);
 }
 
 int EightBit::Rom::load(std::ifstream& file, const int writeOffset, const int readOffset, const int limit) {

src/UnusedMemory.cpp

@@ -3,10 +3,10 @@
 
 #include <cassert>
 
-EightBit::UnusedMemory::UnusedMemory(const size_t size, const uint8_t value) noexcept
+EightBit::UnusedMemory::UnusedMemory(const uint16_t size, const uint8_t value) noexcept
 : m_size(size), m_value(value) {}
 
-size_t EightBit::UnusedMemory::size() const noexcept {
+uint16_t EightBit::UnusedMemory::size() const noexcept {
 	return m_size;
 }