T100MD1616 plc

[beginner]

Hi, im just a beginner working with plcs and ladder logic and need some help.

I am trying to write a program using ladder logic to do the following:

i have a joystick that when a user presses any of the arrows (i.e left, right, up or down) certain messages must be displayed. for example: when you press the right button the frequency should be displayed and when you press it again you it should display maybe the temperature and so on.  

the problem i am having is how to write a program that when the user presses the left button, it should display the previous display i.e frequency and so on. the program should also allow the user to increase the value or decrease it using the up and down buttons.

Could someone please help me?

[support]

You can follow the example program "SetTimCtr_SV.PC5" that can be found in the "usr\samples" folder under the TRiLOGI installation directory which essentially does similar thing to what you want to do. It let you change the timer and counter set values using just 3 push buttons. Try to simulate it on your PC and you can see the effect.