Power Down

[pigeek]

in the middle of running programs, my NXT just shuts down. its usually after 5 minutes (like theres been no activity). i drove my car in circles and it just shut down.

any suggestions or ideas how to keep it from happening? i'm doing a mapping project and it doesnt have time to map a certain area before it shuts down.

[mdsmitty]

You most likely need to replace or charge your batteries.

[pigeek]

i've charged the batteries. its like the robot thinks its being inactive and powers down even when its running. its always after 5 minutes also which is the standard inactivity shut down time

[JavaMan]

I had the same problem. You need to change the setting on how long it take before the nxt goes to sleep.

Jman

[gloomyandy]

Just to clarify. I assume you are using iCommand with the standard firmware. leJOS does not have any powerdown after a period options.... It will not auto-powerdown.

Andy

[NMMDev]

Sorry to bring this up again, but I appear to be having exactly the same problem.

Regardless of what it's doing (idle or running a program), my NXT shuts down at about the 5 minute mark. I need it to be on indefinitely.

- I have set the Sleep Time to every value from 0 through to 10.

- I have used fresh batteries.

- I am using LeJOS 0.8, not iCommand.

Anyone else have this problem?

[gloomyandy]

Hi,
so just to be clear. If you run a leJOS program on the nxt (i.e. you download and run the program), that loops forever updating the screen with say the current time, then it will shutdown after 5 minutes? Have you actually tried doing exactly this?

There is no timeout logic in the firmware so I would be very surprised if the NXT shuts down in the above case. The only timeout logic is in the leJOS menu program (which is why it may shut down if you are running a program on your PC that controls the NXT, remotely)....

Andy

[NMMDev]

Hi Andy

I have a test app that runs a motor backwards and forwards indefinitely. This dies after 5 minutes.

If I switch on the brick and leave it (nothing running), it shuts down after 5 minutes.

I am not connecting via either USB or Bluetooth. Just to be sure, I unplugged the USB.

[pEhrlich]

Hmm. I think I remember something like this when I was just starting out, I had a program for a car that would drive motors forever (I would just be changing speed to control it.) After about 5 mins, the brick would shut off. Unfortunately I can't find the thread on it to tell you why, but I would suggest running a loop test (something similar to what Andy said,) as the motor operator might be different. Someone else will know more than I

[NMMDev]

And just to be absolutely absolutely clear...

This fails at the the 5 minute mark.

Code: Select all

import lejos.nxt.*;

public class Test
{
   public static void main(String[] args)
   {
      new Test();
   }

   Test()
   {
      int i = 0;
      
      while(true)
      {
         i++;
         LCD.drawString(""+i, 0, 0);
      }
   }

}

[gloomyandy]

When you say fails... Do you mean that the device is gets powered off. I assume you can simply restart it by pressing the orange key when it is in that state? I just want to check to see if it has powered off or has got locked up in some way...

Andy

[NMMDev]

It powers off. As you say, I press the orange button and it starts up again.

[gloomyandy]

Interesting... I'll try it on my NXTs later.... I assume you are running 0.8?

Andy

[NMMDev]

Yes

Thanks!

[gloomyandy]

Hi,
I've just had three NXTs (2 with Lego rechargeable batteries and one with normal batteries) running for about an hour (at which point I turned them off). So I don't think this is a general problem. What type of batteries are you using? The NXT does have a thermal fuse device to protect it, I wonder if your NXT is faulty and is overheating this?

Andy