diff --git a/led.c b/led.c
index 564b721..f972ad0 100644
--- a/led.c
+++ b/led.c
@@ -1,4 +1,5 @@
 
+#include <stdlib.h>
 #include <parapin.h>
 
 #define LED_A LP_PIN02
@@ -45,6 +46,12 @@ int main()
 
     /* set up pins as output pins */
     pin_output_mode(LED_ALL);
+
+    if (argc == 2)
+    {
+        int value = atoi(argv[1]);
+        turnOnDigit(2, value % 10);
+    }
 }
 
 void turnOnDigit(int digitPosition, int value)