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NEED HELP! The motors are running without being told to. 
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Joined: Tue May 15, 2012 7:46 am
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Post NEED HELP! The motors are running without being told to.
We are working on a PLTW project and we just set up all of the sensors, connected it to the computer, and input values from -127 to 127 but the motors just started and won't stop. Can anyone help?


Tue May 15, 2012 7:54 am
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Post Re: NEED HELP! The motors are running without being told to.
Are you trying to connect 2 wire motors directly to 3 wire motor ports? If so this is your problem - you should use the motor controller 29 cables between the motor and Cortex.

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Jesse Flot
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Tue May 15, 2012 1:15 pm
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Post Re: NEED HELP! The motors are running without being told to.
Hi !
I'm experiencing the same problem, so I though I'll describe it here in more details.

I'm using examplary code 'single joystick control.c' for testing and I have problems with motors whenever connection between Cortex and Joystick is lost.

I have a feeling that ( when there's no connection ) some default values for joystick channels are assumed. And they're not set to zero! They're set to maximum or minimum values, therefore this piece of code:
Code:
 while(1 == 1)
  {
      motor[leftMotor]  = (vexRT[Ch2] + vexRT[Ch1])/2;  // (y + x)/2
      motor[rightMotor] = (vexRT[Ch2] - vexRT[Ch1])/2;  // (y - x)/2
  }

makes my robot move in a circle (it's right motor is on full speed, while left motor is not moving).

Is there any possibility to add sth like this

Code:
if(noConnectionWithJoystick)
{
     motor[leftMotor]  = 0;
     motor[rightMotor] = 0;
}

in Robotc? To prevent robot behaving like crazy?


Fri Aug 03, 2012 10:29 am
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Post Re: NEED HELP! The motors are running without being told to.
Do you still experience this same problem when the 9V backup battery is plugged in?

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Sat Aug 04, 2012 7:57 am
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Post Re: NEED HELP! The motors are running without being told to.
Can you confirm that your motors are plugged in correctly (no 2-wire motors plugged in on 3-wire ports)?

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Jesse Flot
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Mon Oct 01, 2012 2:56 pm
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Location: Pittsburgh, Pa
Post Re: NEED HELP! The motors are running without being told to.
Make sure everything is updated and the vexnet keys are not broken.

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Wed Oct 10, 2012 10:45 pm
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Joined: Thu Oct 11, 2012 8:34 am
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Post Re: NEED HELP! The motors are running without being told to.
Are you trying to connect 2 wire motors directly to 3 wire motor ports? If so this is your problem - you should use the motor controller 29 cables between the motor and Cortex.

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Thu Oct 11, 2012 8:47 am
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