diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5bdd37c..18c98a8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -97,7 +97,7 @@ add_executable(unit_tests
         sources/Exceptions/DebuggableError.hpp
         tests/CPU/Math/testOthersMath.cpp
         tests/testRectangleMemory.cpp
-)
+        tests/CPU/Math/testCMP.cpp)
 
 # include criterion & coverage
 target_link_libraries(unit_tests criterion -lgcov)
diff --git a/sources/CPU/CPU.hpp b/sources/CPU/CPU.hpp
index e498095..a0598b6 100644
--- a/sources/CPU/CPU.hpp
+++ b/sources/CPU/CPU.hpp
@@ -389,6 +389,8 @@ namespace ComSquare::CPU
 		int RTS(uint24_t, AddressingMode);
 		//! @brief Return from subroutine long.
 		int RTL(uint24_t, AddressingMode);
+		//! @brief Compare Accumulator with Memory.
+		int CMP(uint24_t, AddressingMode);
 
 		//! @brief All the instructions of the CPU.
 		//! @info Instructions are indexed by their opcode
@@ -586,37 +588,37 @@ namespace ComSquare::CPU
 			{&CPU::LDX, 4, "ldx", AddressingMode::AbsoluteIndexedByY, 3}, // BE
 			{&CPU::LDA, 5, "lda", AddressingMode::AbsoluteIndexedByXLong, 4}, // BF
 			{&CPU::BRK, 7, "cpy #-#", AddressingMode::Implied, 2}, // C0
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // C1
+			{&CPU::CMP, 6, "cmp", AddressingMode::DirectPageIndirectIndexedByX, 2}, // C1
 			{&CPU::REP, 3, "rep", AddressingMode::Immediate8bits, 2}, // C2
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // C3
+			{&CPU::CMP, 4, "cmp", AddressingMode::StackRelative, 2}, // C3
 			{&CPU::BRK, 7, "cpy #-#", AddressingMode::Implied, 2}, // C4
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // C5
+			{&CPU::CMP, 3, "cmp", AddressingMode::DirectPage, 2}, // C5
 			{&CPU::BRK, 7, "dec #-#", AddressingMode::Implied, 2}, // C6
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // C7
+			{&CPU::CMP, 6, "cmp", AddressingMode::DirectPageIndirectLong, 2}, // C7
 			{&CPU::INY, 2, "iny", AddressingMode::Implied, 1}, // C8
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // C9
+			{&CPU::CMP, 2, "cmp", AddressingMode::Implied, 2}, // C9
 			{&CPU::DEX, 2, "dex", AddressingMode::Implied, 1}, // CA
 			{&CPU::BRK, 7, "wai #-#", AddressingMode::Implied, 2}, // CB
 			{&CPU::BRK, 7, "cpy #-#", AddressingMode::Implied, 2}, // CC
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // CD
+			{&CPU::CMP, 4, "cmp", AddressingMode::Absolute, 3}, // CD
 			{&CPU::BRK, 7, "dec #-#", AddressingMode::Implied, 2}, // CE
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // CF
+			{&CPU::CMP, 6, "cmp", AddressingMode::AbsoluteLong, 4}, // CF
 			{&CPU::BNE, 2, "bne", AddressingMode::Implied, 2}, // D0
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // D1
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // D2
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // D3
+			{&CPU::CMP, 5, "cmp", AddressingMode::DirectPageIndirectIndexedByY, 2}, // D1
+			{&CPU::CMP, 5, "cmp", AddressingMode::DirectPageIndirect, 2}, // D2
+			{&CPU::CMP, 7, "cmp", AddressingMode::StackRelativeIndirectIndexedByY, 2}, // D3
 			{&CPU::BRK, 7, "pei #-#", AddressingMode::Implied, 2}, // D4
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // D5
+			{&CPU::CMP, 4, "cmp", AddressingMode::DirectPageIndexedByX, 2}, // D5
 			{&CPU::BRK, 7, "dec #-#", AddressingMode::Implied, 2}, // D6
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // D7
-			{&CPU::CLD, 27, "cld", AddressingMode::Implied, 2}, // D8
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // D9
+			{&CPU::CMP, 6, "cmp", AddressingMode::DirectPageIndirectIndexedByYLong, 2}, // D7
+			{&CPU::CLD, 2, "cld", AddressingMode::Implied, 2}, // D8
+			{&CPU::CMP, 4, "cmp", AddressingMode::AbsoluteIndexedByY, 3}, // D9
 			{&CPU::PHX, 3, "phx", AddressingMode::Implied, 1}, // DA
 			{&CPU::BRK, 7, "stp #-#", AddressingMode::Implied, 2}, // DB
 			{&CPU::JML, 7, "jml", AddressingMode::AbsoluteIndirectLong, 2}, // DC
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // DD
+			{&CPU::CMP, 4, "cmp", AddressingMode::AbsoluteIndexedByX, 3}, // DD
 			{&CPU::BRK, 7, "dec #-#", AddressingMode::Implied, 2}, // DE
-			{&CPU::BRK, 7, "cmp #-#", AddressingMode::Implied, 2}, // DF
+			{&CPU::CMP, 5, "cmp", AddressingMode::AbsoluteIndexedByXLong, 4}, // DF
 			{&CPU::BRK, 7, "cpx #-#", AddressingMode::Implied, 2}, // E0
 			{&CPU::SBC, 6, "sbc", AddressingMode::DirectPageIndirectIndexedByX, 2}, // E1
 			{&CPU::SEP, 3, "sep", AddressingMode::Immediate8bits, 2}, // E2
diff --git a/sources/CPU/Instructions/MathematicalOperations.cpp b/sources/CPU/Instructions/MathematicalOperations.cpp
index 4872cbb..776a810 100644
--- a/sources/CPU/Instructions/MathematicalOperations.cpp
+++ b/sources/CPU/Instructions/MathematicalOperations.cpp
@@ -147,4 +147,41 @@ namespace ComSquare::CPU
 		this->_registers.p.n = this->_registers.y & negativeMask;
 		return 0;
 	}
+
+	int CPU::CMP(uint24_t valueAddr, AddressingMode mode)
+	{
+		unsigned negativeMask = this->_registers.p.m ? 0x80u : 0x8000u;
+		unsigned value = this->_bus->read(valueAddr);
+		if (!this->_registers.p.m)
+			value += this->_bus->read(valueAddr + 1) << 8u;
+		unsigned result = this->_registers.a - value;
+		if (this->_registers.p.m)
+			result %= 0x100;
+
+		this->_registers.p.n = result & negativeMask;
+		this->_registers.p.z = result == 0;
+		this->_registers.p.c = this->_registers.a >= result;
+
+		int cycles = !this->_registers.p.m;
+		switch (mode) {
+		case DirectPage:
+		case DirectPageIndirect:
+		case DirectPageIndirectLong:
+		case DirectPageIndexedByX:
+		case DirectPageIndirectIndexedByX:
+		case DirectPageIndirectIndexedByYLong:
+			cycles += this->_registers.dl != 0;
+			break;
+		case AbsoluteIndexedByX:
+		case AbsoluteIndexedByY:
+			cycles += this->_hasIndexCrossedPageBoundary;
+			break;
+		case DirectPageIndirectIndexedByY:
+			cycles += this->_registers.dl != 0 + this->_hasIndexCrossedPageBoundary;
+			break;
+		default:
+			break;
+		}
+		return cycles;
+	}
 }
\ No newline at end of file
diff --git a/tests/CPU/Math/testCMP.cpp b/tests/CPU/Math/testCMP.cpp
new file mode 100644
index 0000000..47968d4
--- /dev/null
+++ b/tests/CPU/Math/testCMP.cpp
@@ -0,0 +1,73 @@
+//
+// Created by anonymus-raccoon on 4/6/20.
+//
+
+#include <criterion/criterion.h>
+#include <bitset>
+#include "../../tests.hpp"
+#include "../../../sources/SNES.hpp"
+using namespace ComSquare;
+
+Test(CMP, underflow)
+{
+	Init()
+	snes.cpu->_registers.p.m = true;
+	snes.cpu->_registers.a = 0;
+	snes.wram->_data[0] = 0x1;
+	snes.cpu->CMP(0x0, ComSquare::CPU::AddressingMode::Implied);
+	cr_assert_eq(snes.cpu->_registers.p.c, false, "The carry flags should not be set.");
+	cr_assert_eq(snes.cpu->_registers.p.n, true, "The negative flags should be set.");
+	cr_assert_eq(snes.cpu->_registers.p.z, false, "The zero flags should not be set.");
+}
+
+Test(CMP, zero)
+{
+	Init()
+	snes.cpu->_registers.p.m = true;
+	snes.cpu->_registers.a = 0x5;
+	snes.wram->_data[0] = 0x5;
+	snes.cpu->CMP(0x0, ComSquare::CPU::AddressingMode::Implied);
+	cr_assert_eq(snes.cpu->_registers.p.c, true, "The carry flags should be set.");
+	cr_assert_eq(snes.cpu->_registers.p.n, false, "The negative flags should not be set.");
+	cr_assert_eq(snes.cpu->_registers.p.z, true, "The zero flags should be set.");
+}
+
+Test(CMP, nativeModeZero)
+{
+	Init()
+	snes.cpu->_registers.p.m = false;
+	snes.cpu->_registers.a = 0x5000;
+	snes.wram->_data[0] = 0x00;
+	snes.wram->_data[1] = 0x50;
+	snes.cpu->CMP(0x0, ComSquare::CPU::AddressingMode::Implied);
+	cr_assert_eq(snes.cpu->_registers.p.c, true, "The carry flags should be set.");
+	cr_assert_eq(snes.cpu->_registers.p.n, false, "The negative flags should not be set.");
+	cr_assert_eq(snes.cpu->_registers.p.z, true, "The zero flags should be set.");
+}
+
+Test(CMP, nativeModeNothing)
+{
+	Init()
+	snes.cpu->_registers.p.m = false;
+	snes.cpu->_registers.a = 0x8000;
+	snes.wram->_data[0] = 0x00;
+	snes.wram->_data[1] = 0x50;
+	snes.cpu->CMP(0x0, ComSquare::CPU::AddressingMode::Implied);
+	cr_assert_eq(snes.cpu->_registers.p.c, true, "The carry flags should be set.");
+	cr_assert_eq(snes.cpu->_registers.p.n, false, "The negative flags should not be set.");
+	cr_assert_eq(snes.cpu->_registers.p.z, false, "The zero flags should not be set.");
+}
+
+Test(CMP, negative)
+{
+	Init()
+	snes.cpu->_registers.p.m = false;
+	snes.cpu->_registers.a = 0xB000;
+	snes.wram->_data[0] = 0x00;
+	snes.wram->_data[1] = 0x10;
+	snes.cpu->CMP(0x0, ComSquare::CPU::AddressingMode::Implied);
+	cr_assert_eq(snes.cpu->_registers.p.c, true, "The carry flags should be set.");
+	cr_assert_eq(snes.cpu->_registers.p.n, true, "The negative flags should be set.");
+	cr_assert_eq(snes.cpu->_registers.p.z, false, "The zero flags should not be set.");
+}
+