How do I scroll strings from different programs on ONE LED message display board

Currently I have 14 different programs for 14 different assembly lines. In each program if a knob is turned, then an integer is sent via a MSG function to a seperate PLC for the LED display. How do I scroll multiple strings on the message display?

Example: Line 1's downtime knob is turned. Therefore, on the LED display the message is: (4:58=downtime in minutes and seconds)

Line 1 4:58 (4:58=downtime in minutes and seconds)

If I turn on Line's 1 AND 2 then the message is:

Line 2 2:37 (it never shows Line 1)

How do I get the LED display to scroll all the Line #'s that are down and their indvidual downtimes?

Let me see if I understand. Each machine that is down sends a message to one central PLC which then handles the message display. If so, make sure that each PLC writes to a diffent area in the target PLC. Then in that PLC, step through the areas for valid 'down time' messages. Display that message for a given amount of time, then step to the next area. If there is no valid message then immediately step to the next. This way all valid messages are shown for a minimum amount of time. While this wouldn't technically be a 'scroll' it would show all the messages.

Check out this old post.

Here

This post is basically about what Bernie is talking about, it sounds like your program is taking whatever the most recent change is and sends it to the PLC, it's not continually checking for inputs to be on, just looking for a change.

you might try a FIFO in the master plc and let it index after a given amount of time then index again and so on.