diff --git a/mini-beieli-provision.go b/mini-beieli-provision.go
index 1bb990f..fdb2ead 100644
--- a/mini-beieli-provision.go
+++ b/mini-beieli-provision.go
@@ -12,6 +12,8 @@ import (
 )
 
 func RandomEUI64() string {
+	r := rand.New(rand.NewSource(time.Now().UnixNano()))
+
 	var letter = []rune("ABCDEF0123456789")
 
 	b := make([]rune, 16+7)
@@ -19,7 +21,7 @@ func RandomEUI64() string {
 		if (i+1)%3 == 0 {
 			b[i] = '-'
 		} else {
-			b[i] = letter[rand.Intn(len(letter))]
+			b[i] = letter[r.Intn(len(letter))]
 		}
 	}
 	return string(b)
@@ -38,6 +40,9 @@ func sendCommand(p *serial.Port, command string, waitForOk bool) string {
 	if waitForOk {
 		loop = 10
 	}
+
+	time.Sleep(200 * time.Millisecond)
+
 	for i := 0; i < loop; i++ {
 		// ignoring error as EOF raises error on Linux
 		n, _ := p.Read(buf)
@@ -53,14 +58,15 @@ func sendCommand(p *serial.Port, command string, waitForOk bool) string {
 }
 
 func main() {
-	if len(os.Args) != 2 {
-		fmt.Println("usage: " + filepath.Base(os.Args[0]) + " <DevEUI>")
+	if len(os.Args) != 3 {
+		fmt.Println("usage: " + filepath.Base(os.Args[0]) + " <SerialDevice> <DevEUI>")
 		os.Exit(1)
 	}
 
-	deveui := os.Args[1]
+	serialdev := os.Args[1]
+	deveui := os.Args[2]
 
-	c := &serial.Config{Name: "/dev/ttyUSB1", Baud: 115200, ReadTimeout: time.Second * 1}
+	c := &serial.Config{Name: serialdev, Baud: 115200, ReadTimeout: time.Second * 1}
 	s, err := serial.OpenPort(c)
 	if err != nil {
 		log.Fatal("Problem mit Serial Interface")