project startup vi

[tilky]

I am making a simple drive project which allows you to either drive with tank or arcade drive, depending on keyboard input. There are 3 different vi's in this project. How would i set which one runs first?

[Alan Anderson]

Do you want to run all three in sequence, with the order depending on a user choice? Or do you want to run only one of the three based on what the user selects?

Are you planning to have the robot controller get information from the Driver Station keyboard?

[tilky]

well, i want it to load with an initial vi that reads the keyboard input. Depending on if A or T is pressed, it will run either the tank drive vi or the arcade drive vi.

[Alan Anderson]

The Driver Station program does not pass keyboard information to the robot. You should think about other ways to select arcade vs. tank drive, such as a joystick button or a switch on the Cypress I/O board (which doesn't have to be a real switch; you can use the emulated I/O on the Driver Station tab).

Use a Case block to run either the Arcade or Tank drive functions. Which one gets run will depend on the select input to the Case, and that should come from the switch you've chosen.

Does this help?

[tilky]

oh, thought it would get keyboard. Ok. Can you explain "Case Block"?

[plnyyanks]

Also called a case structure, this is basically equivalent to an if statement and a switch statement as found in some text based languages. Wire your selector value to the node on the left side of the rectangle and put the code you want to execute in each state in the corresponding subdiagram.

NI Reference

[tilky]

oh, ok. Didn't recognize the name. I know what that is. The problem that i found was that it wouldn't keep the value. I fixed this by putting a while loop inside the case structure.