Watchdog Function Not Functioning

[virtuald]

Hey Will,

WPILib has the motor safety stuff built in and enabled for RobotDrive to make it harder for the robot to do something like go into an infinite loop and have all of the motors going at full blast.

Basically, if you don't tell the motors to do something within 100ms or so, then this error will occur. You can solve it by ensuring that you do something with robot drive each time teleopPeriodic is called.

You can run the following code in the simulator to demonstrate the problem and its solution:

import wpilib

class MyRobot(wpilib.IterativeRobot):

    def robotInit(self):
        self.joystick = wpilib.Joystick(0)
        self.robot_drive = wpilib.RobotDrive(1,2)

    def teleopPeriodic(self):
        if not self.joystick.getTrigger():
            self.robot_drive.arcadeDrive(self.joystick)

if __name__ == '__main__':
    wpilib.run(MyRobot)

If you run this code and stick it in teleop, then all is well, as robot drive is getting called on each loop. However, if you enable the trigger button on the first joystick, then the annoying robot safety output messages will start appearing -- because you're no longer calling robot drive.

Does that make sense?