# Connecting Mindstorm Lego roboter
**URL:** https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354
**Category:** Electronics (Arduino, etc.)
**Created:** [May 1, 2020, 4:15pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354 "2020-05-01T16:15:10Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@kanktonk](https://discourse.processing.org/u/kanktonk)
#### Post date: [May 1, 2020, 4:15pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/1 "2020-05-01T16:15:10Z")
Hi im an art student from gemany and im working on a project with processing.
I have a mistake in my code and I can t figure out how to solve it. If you have any advice it would save me
a lot of time. I try to connect to my old Mindstorm Lego roboter.
Processing shows me this Error when i try to run the programm:
> jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> at jssc.SerialPort.openPort(SerialPort.java:164)
> at pt.citar.diablu.nxt.protocol.NXTCommBluetoothSerialChannelJSSC.openPort(Unknown Source)
> at pt.citar.diablu.nxt.protocol.NXTCommBluetoothSerialChannelJSSC.(Unknown Source)
> at pt.citar.diablu.processing.nxt.LegoNXT.(Unknown Source)
> at sketch\_200501a.setup(sketch\_200501a.java:60)
> at processing.core.PApplet.handleDraw(PApplet.java:2432)
> at processing.awt.PSurfaceAWT$12.callDraw(PSurfaceAWT.java:1547)
> at processing.core.PSurfaceNone$AnimationThread.run(PSurfaceNone.java:313)
> Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
I would really appreciate if you can help me!
This is my code:
```auto
/*
* NXTCommTest.pde
*
* Created on 07 de March 2007
* Modified on 14 August 2014
*
* NXTComm: A java library to control the NXT Brick.
* This is part a of the DiABlu Project (http://diablu.jorgecardoso.org)
*
* Copyright (C) 2007 Jorge Cardoso
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* You can reach me by
* email: jorgecardoso <> ieee org
* web: http://jorgecardoso.org
*/
import processing.serial.*;
import pt.citar.diablu.processing.nxt.*;
int power = 50;
LegoNXT lego;
void setup() {
size(400, 400);
lego = new LegoNXT(this, "/dev/tty.NXT-DevB");
frameRate(10);
}
void draw() {
}
void keyPressed() {
println(key);
if (key == '1') {
lego.motorForwardLimit(LegoNXT.MOTOR_A, power, 360);
}
else if (key == '2') {
lego.motorForward(LegoNXT.MOTOR_A, power);
}
else if (key == '+') {
power += 5;
println(power);
}
else if (key == '-') {
power -= 5;
println(power);
}
else if (key =='q') {
lego.motorHandBrake(LegoNXT.MOTOR_A);
}
else if (key == 's') {
System.out.println("TL: " + lego.getMotorTachoLimit(LegoNXT.MOTOR_A) +
" TC: " +lego.getMotorTachoCount(LegoNXT.MOTOR_A) +
" BTC: " + lego.getMotorBlockTachoCount(LegoNXT.MOTOR_A) +
" RC: " + lego.getMotorRotationCount(LegoNXT.MOTOR_A) );
} else if (key == 'r') {
lego.resetMotorPosition(LegoNXT.MOTOR_A, false);
}
}
void stop() {
println("Stop");
lego.motorStop(LegoNXT.MOTOR_A);
}
```
---
### Author:  [@glv](https://discourse.processing.org/u/glv)
#### Post date: [May 1, 2020, 4:39pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/2 "2020-05-01T16:39:55Z")
Hello,
Welcome to forum.
Please format your code:
[https://discourse.processing.org/faq#format-your-code](https://discourse.processing.org/faq#format-your-code)
`:)`
---
### Author:  [@Chrisir](https://discourse.processing.org/u/Chrisir)
#### Post date: [May 2, 2020, 12:18pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/3 "2020-05-02T12:18:48Z")
> [@kanktonk](#):
>
> DiABlu Project
maybe you can ask the maker of the DiABlu Project or the writer of the code above.
I don’t know the Lego NXT but maybe you can tell it to clear the port?
Also try another port (physically) on your computer please
---
### Author:  [@kanktonk](https://discourse.processing.org/u/kanktonk)
#### Post date: [May 2, 2020, 12:31pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/4 "2020-05-02T12:31:36Z")
thank you for your awensers, really appreciate it! i tried to rech the maker but he doesn t awenser.
how do i physically do a port?
---
### Author:  [@Chrisir](https://discourse.processing.org/u/Chrisir)
#### Post date: [May 2, 2020, 12:32pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/5 "2020-05-02T12:32:13Z")
I mean just use another usb port on yor computer
---
### Author:  [@glv](https://discourse.processing.org/u/glv)
#### Post date: [May 2, 2020, 12:38pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/6 "2020-05-02T12:38:23Z")
Hello,
I have already explored the link and tested code examples and can offer my insight.
I can assist if you format your code and delete your duplicate post; please do this as a courtesy to others.
Try to cut and paste your code and you will see why this is an issue.
You can go back and edit it.
Also you have a duplicate post:
> [@Coding question for trecking device](https://discourse.processing.org/t/coding-question-for-trecking-device/20385):
>
> Hey I try to use processing together with my old lego mindstorm roboter. I spend a lot of time to research how to combine them and finally found a code online which looked helpfull. But now i get this ERROR can somebody please help me to fix this problem: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy. at jssc.SerialPort.openPort(SerialPort.java:164) at pt.citar.diablu.nxt.protocol.NXTCommBluetoothSerialChannelJSSC.openPort(Unkn…
You should delete this.
`:)`
---
### Author:  [@kanktonk](https://discourse.processing.org/u/kanktonk)
#### Post date: [May 4, 2020, 8:02am UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/7 "2020-05-04T08:02:30Z")
hey thanks for your awenser. I format the code now. But when i try to delete the duplicate post it says that I dont have permission.
---
### Author:  [@kanktonk](https://discourse.processing.org/u/kanktonk)
#### Post date: [May 4, 2020, 1:20pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/8 "2020-05-04T13:20:35Z")
ahh ok, unfortunately nothing changed its still the same error
---
### Author:  [@kanktonk](https://discourse.processing.org/u/kanktonk)
#### Post date: [May 2, 2020, 11:38am UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/9 "2020-05-02T11:38:05Z")
Hey I try to use processing together with my old lego mindstorm roboter.
I spend a lot of time to research how to combine them and finally found a code online which looked helpfull. But now i get this ERROR can somebody please help me to fix this problem:
> jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> at jssc.SerialPort.openPort(SerialPort.java:164)
> at pt.citar.diablu.nxt.protocol.NXTCommBluetoothSerialChannelJSSC.openPort(Unknown Source)
> at pt.citar.diablu.nxt.protocol.NXTCommBluetoothSerialChannelJSSC.(Unknown Source)
> at pt.citar.diablu.processing.nxt.LegoNXT.(Unknown Source)
> at sketch\_200502a.setup(sketch\_200502a.java:64)
> at processing.core.PApplet.handleDraw(PApplet.java:2432)
> Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> at processing.awt.PSurfaceAWT$12.callDraw(PSurfaceAWT.java:1547)
> at processing.core.PSurfaceNone$AnimationThread.run(PSurfaceNone.java:313)
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
> RuntimeException: jssc.SerialPortException: Port name - /dev/tty.NXT-DevB; Method name - openPort(); Exception type - Port busy.
---
### Author:  [@jeremydouglass](https://discourse.processing.org/u/jeremydouglass)
#### Post date: [May 8, 2020, 7:02pm UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/10 "2020-05-08T19:02:29Z")
I merged these posts.
> [@kanktonk](#):
>
> I spend a lot of time to research how to combine them and finally found a code online which looked helpful
@kanktonk – I hope that you were able to resolve your problem. What did you find online? Where? Can you link to that code, and can you paste it here?
---
### Author:  [@kanktonk](https://discourse.processing.org/u/kanktonk)
#### Post date: [May 10, 2020, 7:55am UTC](https://discourse.processing.org/t/connecting-mindstorm-lego-roboter/20354/11 "2020-05-10T07:55:07Z")
Hi jeremy this is what i found [https://www.dexterindustries.com/howto/connect-the-arduino-and-the-lego-mindstorms-together/](https://www.dexterindustries.com/howto/connect-the-arduino-and-the-lego-mindstorms-together/) but i switched to touchdesigner and arduiono which works quite well