diff --git a/src/main.py b/src/main.py
index 89cd420..6ce4a42 100644
--- a/src/main.py
+++ b/src/main.py
@@ -1,6 +1,28 @@
-def main():
-    print("Hello from dp32-proto!")
+from argparse import ArgumentParser
+from vm import VM
 
+def main():
+    parser = ArgumentParser(
+            prog="DP32-emu",
+            description="simple emulator for DP32")
+    parser.add_argument(
+            "mem_file"
+            )
+    parser.add_argument(
+            "-o",
+            "--output",
+            help="output memory file of virtual machine",
+            default="out.mem"
+            )
+    args = parser.parse_args()
+    print(args)
+    with open(args.mem_file, 'rb') as f:
+        mem = bytearray(f.read())
+    vm = VM(mem)
+    vm.run()
+
+    with open(args.output, 'wb') as f:
+        f.write(vm.mem)
 
 if __name__ == "__main__":
     main()