improve makefile

Author: JulyWitch

Makefile

@@ -9,9 +9,10 @@ I = "put file path here"
 T = "put test file path here"
 E = "put entity name here"
 
+S_TIME = 1us
+
 compile:
 $(GHDL_CMD) -a $(GHDL_FLAGS) $(I) $(T) 
 $(GHDL_CMD) -e $(GHDL_FLAGS) $(E)
-$(GHDL_CMD) -r $(GHDL_FLAGS) $(E) --vcd=$(dir $(I))$(E).vcd --wave=$(dir $(I))$(E).ghw --stop-time=1us
-
+$(GHDL_CMD) -r $(GHDL_FLAGS) $(E) --vcd=$(dir $(I))$(E).vcd --wave=$(dir $(I))$(E).ghw --stop-time=$(S_TIME)