Message Scrolling Code

[Can_Farm]

New to the forum and looking for a bit of advice or a nudge in the right direction.

I am currently working with the Beckhoff Twincat system and an "AdvancedHMI" HMI. I am looking for some help in writing some code.

Currently, I use the PLC to send a one line text message to the HMI to display any type of alarm or fault to help the operator understand what is happening with the equipment.

In the event that more than one of the bits that trigger these messages go high at the same time, I would like to be able to scroll through the multiple messages on the HMI for a certain time period, on an endless loop.

Thanks in advance for any help offered...

 

[L D[AR2P#0.0]]

Here's something I've just tested to give you one idea. Needs some work to clear the alarm message if there is no alarm.

//test data
#abAlarms[55]:=True;
#asAlarms[55]:='Bert55';
#abAlarms[77]:=True;
#asAlarms[77]:='Ernie77';

CASE #iState OF
    #INIT:
        #DisplayTime(IN := false,
                     PT := t#3s);
        #iState := #SCAN;
    #SCAN:
           
     IF #abAlarms[#iIndex] THEN
         #iCurrentAlarm := #iIndex;
         #sCurrentAlarm := #asAlarms[#iIndex];
         #iState := #SCROLLDELAY;
     END_IF;
     #iIndex:=#iIndex+1;
     IF #iIndex > #NUMBEROFALARMS THEN
         #iIndex := 1;
     END_IF;
 
        
    #SCROLLDELAY:
        #DisplayTime(IN := True,
                     PT := t#3s);
        IF #DisplayTime.Q THEN
            #iState := #INIT;
        END_IF;
END_CASE;

 

[Can_Farm]

Here's something I've just tested to give you one idea. Needs some work to clear the alarm message if there is no alarm.

//test data
#abAlarms[55]:=True;
#asAlarms[55]:='Bert55';
#abAlarms[77]:=True;
#asAlarms[77]:='Ernie77';

CASE #iState OF
    #INIT:
        #DisplayTime(IN := false,
                     PT := t#3s);
        #iState := #SCAN;
    #SCAN:
           
     IF #abAlarms[#iIndex] THEN
         #iCurrentAlarm := #iIndex;
         #sCurrentAlarm := #asAlarms[#iIndex];
         #iState := #SCROLLDELAY;
     END_IF;
     #iIndex:=#iIndex+1;
     IF #iIndex > #NUMBEROFALARMS THEN
         #iIndex := 1;
     END_IF;
 
        
    #SCROLLDELAY:
        #DisplayTime(IN := True,
                     PT := t#3s);
        IF #DisplayTime.Q THEN
            #iState := #INIT;
        END_IF;
END_CASE;

Thank you!

One question. Please excuse my ignorance. When it comes to ST, I am a novice at best.

Looking in your code, can you give me a quick explanation of what #INIT and #SCAN are?

Are these declared variables or symbolic constants?

 

[Can_Farm]

The error I am getting is on the line where #INIT is located. The error is..."Integer Number or Symbolic Constant expected".

 

[L D[AR2P#0.0]]

Here's the block interface:

 

[cardosocea]

The error I am getting is on the line where #INIT is located. The error is..."Integer Number or Symbolic Constant expected".

In your block, create the variables INIT, SCAN and SCROLLDELAY and give them a number (must be different for each). To make the code like it is here, you can declare the variables as CONSTANT. See below:

https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_plc_intro/2529284235.html&id=

 

[Can_Farm]

I created the variables and assigned them each a different number. Still getting the same error. Can you see where the problem is before I pull my hair out?

I attached picture of code.

 

[L D[AR2P#0.0]]

You needs constants to be declared - your screen shot doesn't clarify this.

 

[pal]

Hopefully attached is a 3 rung ladder circuit for an alarm banner . It is written for a Micrologix ML1000 in RS Logix 500 . Please note the routine includes a jump to the start of the same rung and if you have a large number of alarms the program scan time may be exceeded . In this case the alarms will need splitting into more than 1 scan .