Creating Menu

[meiya777]

Am very new to PLC, and waiting for my first T100MD. Just want to know  how I can make a simple menu on the LCD-420 with UP/DOWN button as inputs? Make it clear for you:

Option 1: print GOOD MORNING
Option 2: print GOOD AFTERNOON
Option 3: print GOOD EVENING
Option 4: print GOOD NIGHT

User choose any of the options, and PLC will execute the command and send it to LCD-420

[support]

You can use an input as up button and another input as down button:


   Up          C1
|--||-------[UpCtr]

   Down         C1
|--||-------[DnCtr]
   
   Up        Fn_#1
|--||------{dCusF}
|  Down  |    
|--||----+



C1 is an up/down counter with SV = 3. So when you press the Up button or down button more than 4 times it will scroll to 0 or SV.

Fn_#1 is a custom function which will check the value of C1 (ctrpv[1] if using counter #1) and determine what message to send to LCD.

There are other ways of doing it, e.g. instead of using a counter such as C1, you can use any variable as a counter.

   E.g.  X = X + 1
          If X >= 4 THEN return : ENDIF

That way you can forbid scrolling beyond the limit.
         
You can simulate the above in your education version of TRiLOGI software before your T100MD+ arrived.