Just starting with MRL.

My board is connected and when I attach I am not getting any movement.  The UNO is blinking the TX and RX leds when I move the slider.

the servo desn't move when I attach the slder. (running windows)

All MRL files downloaded, and services started.  Finger starter servo works with another sketch but I can't control with slider in MRL.  The uno R3 is connected



6 years 9 months ago

Hi Slowbot,

What sketch are you using ?

Are you sure you connected your servo to the right pin ?



6 years 9 months ago

Hey Slowbot ! welcome !

Seems like you are using an old version of myrobotlab (1.0.119) ...

Delete the old folder or just make a new one and install the latest myrobotlab.jar inside...

Here is where you can find the latest : http://mrl-bucket-01.s3.amazonaws.com/current/develop/myrobotlab.jar

Once you install all the services, open the arduino service and copy the .ino sketch which appear in the tab... Then use the normal Arduino IDE to upload it to your arduino UNO...

Let us know



6 years 9 months ago

Alessandruino,  Thank you for your help.  Yes, I was using the older version 1.0.119.  I deleted old version and downloaded the latest .JAR.

 MRL GUI is 947.  Downloaded all services and restarted.  When I start Arduino service it loads tabs but locks up. Doesn't do this  loading other services.  As soon as I load Arduino it locks up, I can only close.

Kind of worse.

Beetlejuice, First off thank you for your help.  The sketch is GroG version 21 from arudino service.  I double checkpin setup and I am on pin3 PWM and selected pin 3 in the attach slider service. 


6 years 9 months ago

In reply to by Slowbot

The last skecth is version 25, but if you followed what alessandruino said, you must have it

But i used the wrong word, i meaned , what's your python script ... or maybe you just start it with the gui .

When the arduino tab lock up, do you see a red message at the bottom of MRL windows ?

Is there an error logged in the bottom window of "python" tab ?

if you can't do anything, when you close MRL window, go in MRL folder and you will find a log in a text file called "myrobotlab" . open it and see if an error happened



Yes the error message is;  ERROR [Decoder _stdin] c.m.s.Cli [Cli.java:225} leaving Decoder.

I detached the runtime tab to watch the Python tab.  No error message, it opened  a blank screen at bottom.  Like a Cmd prompt screen. 

I can't delete MRL to reinstall. due to  file open Java se binary.

Thank you,


Hi Slowbot,

  (I assume you're on windows..) If you bring up task manager, you might see a bunch of java processes hanging around.  When you exit MyRobotLab it leaves these java processes running.  I recommend killing/ending those processes and starting MRL back up.  This is a known issue.. we call them "zombie java processes"  and you must kill them!  :)

good luck,


Ahoy Slowbot,  I noticed something in your last no-worky that you sent.

It seems that your system is only reporting the following 2 com ports:


Are you sure that the arduino is installed and that your operating system is seeing it correctly?  Also, are you actually using windows 7 32bit ?  I was curious because it seems odd that you're using a 32bit operating system if it's windows 7.  (it's possibly, just curious)

Anyway,  you should open up  the "device manager" in windows and make sure that you see your arduino listed under the com ports section.  You should see the arduino listed under the "Ports (COM & LPT)" section if the arduino is being recognized by the operating system.



Hello Kwatters,  I am using Windows 7 64bit OS.  Got everthing clean up and MRL is working and is seeing com4 port.  I even can see  RX and TX lights flash when I move the slider but the servo doesn't move.  just sent a no-worky.   thanks for the help.

Did this get resolved?  I just got the hand together and attempted to use MyRobotLab on Mac and now Windows 10 and I cannot get any finger movement.  It seems the Tx and Rx LEDs are lighting up when I move the slider.  Help please?

  Bradap, Not resolved but not from lack of elphere everyone has been great. I just haven't ben able spend anytime working this.  From my limited experience I have donethse things

1. got the right verion of MRL see alessadro post

2. killed all The ZOMBIES

3. made sure COM4 was selected an connected also pin 3

Still no worky.

even though I found a sketch version in the forum that compiled and loaded to the UNO.  The Audrino Service version 25  will not compile.

I am thinking that the sketch I am using needs tweaking or it is not seeing pin 3 control for the servo.


Good luck keep at it.