diff --git a/simulator/Makefile b/simulator/Makefile
new file mode 100644
index 0000000..c5aeecf
--- /dev/null
+++ b/simulator/Makefile
@@ -0,0 +1,17 @@
+CC=gcc
+CFLAGS=-Wall -Werror -O2 -ansi -std=gnu99
+LIBS=-lpthread
+
+OUT = sim
+OBJ = addrmode.o alu.o bus.o core.o decoder.o exec.o main.o memory.o serial.o
+
+%.o: %.c
+	$(CC) -c -o $@ $< $(CFLAGS)
+
+$(OUT): $(OBJ)
+	gcc -o $@ $^ $(CFLAGS) $(LIBS)
+
+.PHONY: clean
+
+clean:
+	rm -f *.o $(OUT) 
diff --git a/simulator/main.c b/simulator/main.c
index f6a6105..fb2535a 100644
--- a/simulator/main.c
+++ b/simulator/main.c
@@ -13,7 +13,7 @@ int main(int argc, char *argv[])
 
 	while (1) {
 		core_step();
-		thread_sleep(1000);
+		thread_sleep(1000000);
 	}
 
 	return 0;