diff --git a/build.sh b/build.sh
index 59b9853..9272b00 100755
--- a/build.sh
+++ b/build.sh
@@ -1,2 +1,2 @@
 mkdir ./bin
-clang -o ./bin/r16e ./emu/main.c ./emu/cpu/ram.c ./lib/carg-parse/carg-parse.c
\ No newline at end of file
+clang -o ./bin/r16e ./emu/main.c ./emu/cpu/ram.c ./emu/cpu/register.c ./emu/cpu/stack.c ./lib/carg-parse/carg-parse.c
\ No newline at end of file
diff --git a/emu/cpu/instruction.c b/emu/cpu/instruction.c
new file mode 100644
index 0000000..e409636
--- /dev/null
+++ b/emu/cpu/instruction.c
@@ -0,0 +1,41 @@
+#include "./instruction.h"
+
+r16_int GetArgVal(ArgumentInfo argInfo, r16_int arg)
+{
+    
+}
+
+void ExecuteInstruction(CpuInstructions instruction, ArgumentInfo arg1Info,
+                        ArgumentInfo arg2Info, r16_int arg1, r16_int arg2)
+{
+    switch (instruction)
+    {
+        case HLT:
+            printf("program halted\n");
+            exit(0);
+        case ADD:
+        case SUB:
+        case MUL:
+        case DIV:
+        case LBS:
+        case RBS:
+        case BAN:
+        case BOR:
+        case BXO:
+        case BNO:
+        case PUS:
+        case POP:
+        case JMP:
+        case JEQ:
+        case JNZ:
+        case CAL:
+        case RET:
+        case REG:
+        case INT:
+        case INP:
+        case OUT:
+        case DIN:
+        case DOT:
+        case MOV:
+    }
+}
\ No newline at end of file
diff --git a/emu/cpu/instruction.h b/emu/cpu/instruction.h
new file mode 100644
index 0000000..8cb3f5c
--- /dev/null
+++ b/emu/cpu/instruction.h
@@ -0,0 +1,9 @@
+#ifndef EMU_CPU_INSTRUCTION_H
+#define EMU_CPU_INSTRUCTION_H
+
+#include "../cpu_const.h"
+#include "./ram.h"
+#include "./register.h"
+#include "./stack.h"
+
+#endif
\ No newline at end of file
diff --git a/emu/cpu/stack.c b/emu/cpu/stack.c
index 3da01d0..cd378cd 100644
--- a/emu/cpu/stack.c
+++ b/emu/cpu/stack.c
@@ -1,13 +1,31 @@
 #include "./stack.h"
+#include <stdlib.h>
+#include <stdio.h>
 
-r16_int pop()
+r16_int StackPop()
 {
     #ifdef DO_STACK_CHECKS
-    if ()
+    if (GetRegister(SP).u == 0)
+    {
+        fprintf(stderr, "STACK UNDERFLOW\n");
+        exit(-1);
+    }
     #endif
+
+    SetRegister(SP, (r16_int){ GetRegister(SP).u - 1 });
+    return GetValue((r16_int){ GetRegister(SP).u + STACK_LOCATION });
 }
 
-void push(r16_int value)
+void StackPush(r16_int value)
 {
+    #ifdef DO_STACK_CHECKS
+    if (GetRegister(SP).u >= STACK_SIZE)
+    {
+        fprintf(stderr, "STACK OVERFLOW\n");
+        exit(-1);
+    }
+    #endif
 
+    SetValue((r16_int){ GetRegister(SP).u + STACK_LOCATION }, value);
+    SetRegister(SP, (r16_int){ GetRegister(SP).u + 1 });
 }
diff --git a/emu/cpu/stack.h b/emu/cpu/stack.h
index 28e4111..dc34ab7 100644
--- a/emu/cpu/stack.h
+++ b/emu/cpu/stack.h
@@ -9,4 +9,7 @@
 
 #define DO_STACK_CHECKS
 
+r16_int StackPop();
+void StackPush(r16_int value);
+
 #endif
\ No newline at end of file