Fix upload issue with Due Programming port

upload/upload.go

@@ -143,37 +143,48 @@ func reset(port string, wait bool, l Logger) (string, error) {
 
 	// Get port list before reset
 	ports, err := serial.GetPortsList()
-	debug(l, "Get port list before reset")
+	info(l, "Get port list before reset")
 	if err != nil {
 		return "", errors.Wrapf(err, "Get port list before reset")
 	} else {
-		debug(l, ports)
+		info(l, ports)
 	}
 
-	// Open port
-	mode := &serial.Mode{
-		BaudRate: 1200,
+	// Touch port at 1200bps
+	err = touchSerialPortAt1200bps(port, l)
+	if err != nil {
+		return "", errors.Wrapf(err, "1200bps Touch")
+	}
+
+	// Wait for port to disappear and reappear
+	if wait {
+		port = waitReset(ports, l)
 	}
-	p, err := serial.Open(port, mode)
-	debug(l, "Open port", port)
+
+	return port, nil
+}
+
+func touchSerialPortAt1200bps(port string, l Logger) error {
+	info(l, "Touching port ", port, " at 1200bps")
+
+	// Open port
+	p, err := serial.Open(port, &serial.Mode{BaudRate: 1200})
 	if err != nil {
-		return "", errors.Wrapf(err, "Open port %s", port)
+		return errors.Wrapf(err, "Open port %s", port)
 	}
+	defer p.Close()
 
 	// Set DTR
 	err = p.SetDTR(false)
-	debug(l, "Set DTR")
+	info(l, "Set DTR off")
 	if err != nil {
-		return "", errors.Wrapf(err, "Can't set DTR")
+		return errors.Wrapf(err, "Can't set DTR")
 	}
-	p.Close()
 
-	// Wait for port to disappear and reappear
-	if wait {
-		port = waitReset(ports, l)
-	}
+	// Wait a bit to allow restart of the board
+	time.Sleep(200 * time.Millisecond)
 
-	return port, nil
+	return nil
 }
 
 // waitReset is meant to be called just after a reset. It watches the ports connected