diff --git a/M6502/inc/mos6502.h b/M6502/inc/mos6502.h
index 8ac47a6..d6de017 100644
--- a/M6502/inc/mos6502.h
+++ b/M6502/inc/mos6502.h
@@ -372,7 +372,7 @@ namespace EightBit {
 			case 0b011:
 			case 0b101:
 			case 0b111:
-				setByte(MEMPTR(), value);
+				setByte(value);
 				break;
 			case 0b000:
 			case 0b100:
@@ -538,39 +538,33 @@ namespace EightBit {
 		// Operations
 
 		void ASL(int bbb) {
-			auto operand = AM_10(bbb);
-			ASL(operand);
-			AM_10(bbb, operand);
+			const auto result = ASL(AM_10(bbb));
+			AM_10(bbb, result);
 		}
 
 		void ROL(int bbb) {
-			auto operand = AM_10(bbb);
-			ROL(operand);
-			AM_10(bbb, operand);
+			const auto result = ROL(AM_10(bbb));
+			AM_10(bbb, result);
 		}
 
 		void LSR(int bbb) {
-			auto operand = AM_10(bbb);
-			LSR(operand);
-			AM_10(bbb, operand);
+			const auto result = LSR(AM_10(bbb));
+			AM_10(bbb, result);
 		}
 
 		void ROR(int bbb) {
-			auto operand = AM_10(bbb);
-			ROR(operand);
-			AM_10(bbb, operand);
+			const auto result = ROR(AM_10(bbb));
+			AM_10(bbb, result);
 		}
 
 		void DEC(int bbb) {
-			auto operand = AM_10(bbb);
-			adjustNZ(--operand);
-			AM_10(bbb, operand);
+			const auto result = DEC(AM_10(bbb));
+			AM_10(bbb, result);
 		}
 
 		void INC(int bbb) {
-			auto operand = AM_10(bbb);
-			adjustNZ(++operand);
-			AM_10(bbb, operand);
+			const auto result = INC(AM_10(bbb));
+			AM_10(bbb, result);
 		}
 
 		void DCP(int bbb) {
@@ -585,15 +579,28 @@ namespace EightBit {
 			A() = SBC(A(), operand);
 		}
 
+		//
+
+		uint8_t DEC(uint8_t value) {
+			const auto result = --value;
+			adjustNZ(result);
+			return result;
+		}
+
+		uint8_t INC(uint8_t value) {
+			const auto result = ++value;
+			adjustNZ(result);
+			return result;
+		}
+
 		void ORA(uint8_t value) {
 			adjustNZ(A() |= value);
 		}
 
 		void SLO(int bbb) {
-			auto operand = AM_01(bbb);
-			ASL(operand);
-			setByte(operand);
-			ORA(operand);
+			const auto result = ASL(AM_01(bbb));
+			setByte(result);
+			ORA(result);
 		}
 
 		void ANDA(uint8_t value) {
@@ -601,10 +608,9 @@ namespace EightBit {
 		}
 
 		void RLA(int bbb) {
-			auto operand = AM_01(bbb);
-			ROL(operand);
-			setByte(operand);
-			ANDA(operand);
+			const auto result = ROL(AM_01(bbb));
+			setByte(result);
+			ANDA(result);
 		}
 
 		void EORA(uint8_t value) {
@@ -612,28 +618,26 @@ namespace EightBit {
 		}
 
 		void SRE(int bbb) {
-			auto operand = AM_01(bbb);
-			LSR(operand);
-			setByte(operand);
-			EORA(operand);
+			const auto result = LSR(AM_01(bbb));
+			setByte(result);
+			EORA(result);
 		}
 
 		void RRA(int bbb) {
-			auto operand = AM_01(bbb);
-			ROR(operand);
-			setByte(operand);
-			A() = ADC(A(), operand);
+			const auto result = ROR(AM_01(bbb));
+			setByte(result);
+			A() = ADC(A(), result);
 		}
 
-		void ROR(uint8_t& output);
+		uint8_t ROR(uint8_t value);
 
-		void LSR(uint8_t& output);
+		uint8_t LSR(uint8_t value);
 
 		void BIT(uint8_t data);
 
-		void ROL(uint8_t& output);
+		uint8_t ROL(uint8_t value);
 
-		void ASL(uint8_t& output);
+		uint8_t ASL(uint8_t value);
 
 		void CMP(uint8_t first, uint8_t second);
 
diff --git a/M6502/src/mos6502.cpp b/M6502/src/mos6502.cpp
index 465986b..03e8bf0 100644
--- a/M6502/src/mos6502.cpp
+++ b/M6502/src/mos6502.cpp
@@ -474,16 +474,18 @@ uint8_t EightBit::MOS6502::pop() {
 
 ////
 
-void EightBit::MOS6502::ROR(uint8_t& output) {
+uint8_t EightBit::MOS6502::ROR(uint8_t value) {
 	const auto carry = P() & CF;
-	setFlag(P(), CF, output & CF);
-	output = (output >> 1) | (carry << 7);
-	adjustNZ(output);
+	setFlag(P(), CF, value & CF);
+	value = (value >> 1) | (carry << 7);
+	adjustNZ(value);
+	return value;
 }
 
-void EightBit::MOS6502::LSR(uint8_t& output) {
-	setFlag(P(), CF, output & CF);
-	adjustNZ(output >>= 1);
+uint8_t EightBit::MOS6502::LSR(uint8_t value) {
+	setFlag(P(), CF, value & CF);
+	adjustNZ(value >>= 1);
+	return value;
 }
 
 void EightBit::MOS6502::BIT(uint8_t data) {
@@ -492,15 +494,17 @@ void EightBit::MOS6502::BIT(uint8_t data) {
 	setFlag(P(), VF, data & VF);
 }
 
-void EightBit::MOS6502::ROL(uint8_t& output) {
-	const uint8_t result = (output << 1) | (P() & CF);
-	setFlag(P(), CF, output & Bit7);
-	adjustNZ(output = result);
+uint8_t EightBit::MOS6502::ROL(uint8_t value) {
+	const uint8_t result = (value << 1) | (P() & CF);
+	setFlag(P(), CF, value & Bit7);
+	adjustNZ(result);
+	return result;
 }
 
-void EightBit::MOS6502::ASL(uint8_t& output) {
-	setFlag(P(), CF, (output & Bit7) >> 7);
-	adjustNZ(output <<= 1);
+uint8_t EightBit::MOS6502::ASL(uint8_t value) {
+	setFlag(P(), CF, (value & Bit7) >> 7);
+	adjustNZ(value <<= 1);
+	return value;
 }
 
 uint8_t EightBit::MOS6502::SBC(const uint8_t operand, const uint8_t data) {