Programming Talon PWM - Java

Technical Programming
#3

Yes using the PWMTalonSRX class

Using the Y cable to connect to ports 0 and 1 respectively.

Currently testing the example code from VS code using tank drive.

    /*----------------------------------------------------------------------------*/

/* Copyright © 2017-2018 FIRST. All Rights Reserved. /
/ Open Source Software - may be modified and shared by FRC teams. The code /
/ must be accompanied by the FIRST BSD license file in the root directory of /
/ the project. /
/----------------------------------------------------------------------------*/

package frc.robot;

import edu.wpi.first.wpilibj.Joystick;
import edu.wpi.first.wpilibj.PWMTalonSRX;
import edu.wpi.first.wpilibj.TimedRobot;
import edu.wpi.first.wpilibj.drive.DifferentialDrive;

/**

  • This is a demo program showing the use of the RobotDrive class, specifically
  • it contains the code necessary to operate a robot with tank drive.
    */
    public class Robot extends TimedRobot {
    private DifferentialDrive m_myRobot;
    private Joystick m_leftStick;
    private Joystick m_rightStick;

@Override
public void robotInit() {
m_myRobot = new DifferentialDrive(new PWMTalonSRX(0), new PWMTalonSRX(1));
m_leftStick = new Joystick(0);
m_rightStick = new Joystick(0);
}

@Override
public void teleopPeriodic() {
m_myRobot.tankDrive(m_leftStick.getY(), m_rightStick.getY());
}
}

#4

Look at your Joystick constructors. You are creating 2 joysticks both on port 0.

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#5

I tried multiple different controller configurations. Only using one controller right now. Also tried the arcade drive example code with the same result.

#6

What are the SRX LEDs doing, both when joysticks are at zero, and when you’re trying to drive forward or reverse?

#7

Flashing red under all instances.

#8

Like this?

Indication: Both LEDs quickly blink red then off. First one LED blinks red, followed immediately by the other, then finally both LEDs are off for a small period of time.
Problem:Limit Switch or Soft Limit Activated

Or together, or alternating, or strobing one direction or the other?

#9

They don’t blink quickly it’s more of a standard pattern of blinking. I feel like they are not either being instantiated or activated

Blinking together

#10

Try

private SpeedController m_Left;
private SpeedController m_Right;

m_Left = new PWMTalonSRX(0);
m_Right = new PWMTalonSRX(1);
m_myRobot = new DifferentialDrive(m_Left, m_Right);
m_leftStick = new Joystick(0);
m_rightStick = new Joystick(1);

Make sure your DS has the Joysticks in the correct USB port.

#11

That seems to indicate that you have reverse throttle all the time (?) or a failed calibration.

The blink codes are on page 32 here:

#12

I think the lights were blinking together but they could’ve been alternating I will have to check that tomorrow I have already left for the night from our lab.

#13

Any chance of a photo of your wiring setup?

What is this Y cable you have mentioned several times?

#14

The lights are alternating which would indicate no pwm signals.

#15

The Y cable links the left motors to 1 pwm signal and same for the right side.

#16

Do the yellow wires on the SRXs connect to the PWM port 0 and 1 pins marked “S” on the RIO, and the green to the Ground symbol ⏚? If reversed or not connected there, this would cause the “no pwm” condition.

#17

I was not there today but the robot got rewired with spark motor controllers and still did not have success. I don’t have the code that was changed but here are the pictures that was sent to me today. We used these sparks last year with no issues.

image
image1142×2030 416 KB
image
image1149×2043 497 KB

#18

Update-
After rewiring with sparks the colors change indicating that sparks were receiving from the signals from the pwm but did not get any movement.

#19

Um - I see four SPARK [original] motor controllers and zero Talon [anything] motor controllers in your pics. What are you actually using?

#20

Updated above. Robot was rewired today with sparks.

#21

SO… this is now an entirely different problem. Did you update your code? If so, what does it look like now? I never did see a link to a repository.

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#22

So after multiple struggling days and switching to Spark motor Controllers the problem has been resolved. We used some new wire connectors this year and overlooked a wiring issue. Thanks for the assistance given and good luck to all competing in the upcoming weeks.

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