diff --git a/src/RS232_unix.c b/src/RS232_unix.c
--- a/src/RS232_unix.c
+++ b/src/RS232_unix.c
@@ -89,7 +89,7 @@ int rs232setparity(rs232port_t fd, rs232
 	}
 }
 
-int rs232setnbstop(rs232port_t fd, int NbStop)
+int rs232setnbstop(rs232port_t fd, rs232stop NbStop)
 {
 	if ((int)fd == -1)
 	{