[FTC]: Java in RobotC for TeleOp

Other FIRST Tech Challenge
1

I need help with programming. I found that you can use certain Java commands in RobotC. So I thought that I could use the Switch command which worked for some things but I have no idea how to make it work for the buttons in the TeleOp phrase.

The syntax for the Switch command is


    switch (*variable*)
    {
       case *condition*:
         *action*
         break;
       case *condition2*:
         *action*
         break;
       default:
         *action*
       break;
    }

or Just watch this YouTube video for more detail on the syntax.

http://www.youtube.com/watch?v=RVRPmeccFT0

This is my proof of concept code for Java in RobotC. It is supposed to display what button is being pressed on the NXT screen. Since this was only a proof of concept, only wrote code for Buttons 1-4 on Game controller #1(Logitech Dual action). The purpose of using the Switch command was to shorten up the code and make it less massive instead of using an IF and ELSE command for every button that will be used.


#pragma config(Hubs,  S1, HTMotor,  HTMotor,  HTMotor,  HTServo)
#pragma config(Motor,  mtr_S1_C1_1,     Intake,        tmotorNormal, openLoop)
#pragma config(Motor,  mtr_S1_C1_2,     Lift,          tmotorNormal, openLoop)
#pragma config(Motor,  mtr_S1_C2_1,     DriveL,        tmotorNormal, openLoop, reversed)
#pragma config(Motor,  mtr_S1_C2_2,     ShooterR,      tmotorNormal, openLoop)
#pragma config(Motor,  mtr_S1_C3_1,     DriveR,        tmotorNormal, openLoop)
#pragma config(Motor,  mtr_S1_C3_2,     ShooterL,      tmotorNormal, openLoop)
#pragma config(Servo,  srvo_S1_C4_1,    WingL,                tServoNormal)
#pragma config(Servo,  srvo_S1_C4_2,    WingR,                tServoNormal)
//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//

#include "JoystickDriver.c"  //Include file to "handle" the Bluetooth messages.

void initializeRobot()
{
  servo[WingL] = 127;  // Reset Left wing position
  servo[WingR] = 127;  // Reset Right wing position
  return;
}

task main()
{
  initializeRobot();

  waitForStart();   // wait for start of tele-op phase
  
  int buttons = joystick.joy1_Buttons; // shortens the joystick.joy1_Buttons variable
  
  while(1)
  {
    getJoystickSettings(joystick); //Updates controls
    switch (buttons)
    {
      case 1:  // checks if button 1 on Joy 1 is being pressed down
        nxtDisplayCenteredTextLine(2, "Button : %d", 1);  // Display "Button: 1"
        break;
      case 2:  // checks if button 2 on Joy 1 is being pressed down
        nxtDisplayCenteredTextLine(2, "Button : %d", 2);  // Display "Button: 2"
        break;
      case 3:  // checks if button 3 on Joy 1 is being pressed down
        nxtDisplayCenteredTextLine(2, "Button : %d", 3);  // Display "Button: 3"
        break;
      case 4:  // checks if button 4 on Joy 1 is being pressed down
        nxtDisplayCenteredTextLine(2, "Button : %d", 4);  // Display "Button: 4"
        break;
      default: // if nothing is being pressed
        nxtDisplayCenteredTextLine(2, "Button : %d",  );  // Display "Button:  "
      break;
    }
  }
}

Thanks in advanced,

Mason Tran
FTC Team 3385
Lead Programmer

2

The problem is the button commands you are using. “joystick.joy1_Buttons” doesn’t work like Joy1Btn, where it outputs the actual button number. Instead, it outputs numbers to the power of 2, like this:

button 1 = 1
button 2 = 2
button 3 = 4
button 4 = 8
button 5 = 16
button 6 = 32
etc…

This is useful to allow for commands where multiple buttons are pressed at once, but can be a pain otherwise. In your script, button 3 should activate case 4, with button 4 activating case 8. Case 3 currently displays when 1 and 2 are pressed togethor, and case 4 displays when button 3 is pressed.

3

^^Truth.

In addition, the joy1_buttons int adds the numbers together if multiple buttons are pressed at once (ex if button 3 (button 3 is 4) and button 4 (button 4 is 8) were pressed at the same time, the result in joy1_buttons would be 12).

Also, your code would only check to see if a single button is pressed each time the loop runs, because you’re using a single switch statement. So, if you had buttons 3 and 4 pressed, the program would only see button 3 as pressed.

You may want to try a loop that checks each button, something like…

for(int i=1;i<=12;i++) {
  if(joy1Btn(i)) {
    switch(i) {
      case 1: /* Button 1 code */ break;
      //...
    }
  if(joy2Btn(i)) {
    switch(i) {
      case 1: /* Button 1 code */ break;
      //...
    }
}

Good job, though. ^^