diff --git a/.gitignore b/.gitignore
index ab22702..279ccc5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@ sillymachine
 *.sib
 *.ali
 *.o
+*.exe
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..9f4c6d2
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,13 @@
+
+default: sillymachine
+
+sillymachine: ./src/sillymachine.adb
+	gnatmake ./src/sillymachine.adb
+
+sillymachine.exe: ./src/sillymachine.adb
+	x86_64-w64-mingw32-gnatmake src/sillymachine.adb -lwinmm -lgdi32	
+
+all: sillymachine sillymachine.exe
+
+clean:
+	rm *.o *.ali sillymachine.exe sillymachine
diff --git a/src/shardware.adb b/src/shardware.adb
index b9ddd24..328bb19 100644
--- a/src/shardware.adb
+++ b/src/shardware.adb
@@ -19,10 +19,7 @@ package body Shardware is
 
   function Bytes_To_I (Instruction : ByteArr) return Integer is
   begin
-    return Integer(My_ShiftI(Instruction (7), 24) 
-    + My_ShiftI(Instruction (8), 16)
-    + My_ShiftI(Instruction (9), 8) 
-    + Integer(Instruction (10)));
+    return Integer(Bytes_To_U(Instruction));
   end Bytes_To_I;
 
   function Bytes_To_U (Instruction : ByteArr) return Unsigned_32 is