diff --git a/firmware/firmware.ino b/firmware/firmware.ino
index fe919c6..c82fd91 100644
--- a/firmware/firmware.ino
+++ b/firmware/firmware.ino
@@ -5,6 +5,7 @@
 #define CMD_SIZE	(5 * 4)
 #define CMD_DATA_LEN	CMD_SIZE * 40
 
+//add
 #define PIN_PULS 5
 #define PIN_DIR 6
 #define PIN_ENABLE 8