Synchronizing 2 digital outputs

[kallileo]

Let's that I want to synchronize 2 digital outputs so the fist DO is ON for 600 ms and a soon it goes to OFF state the second will turn ON for 400 ms and this will continue as long as needed.
What would be the solutions to do something like this?
Is it possible to do this by using PWM?

Let's say that I need to work on a S7-1200 but I would also like to see methods for other PLCs too.

 

[GTUnit]

This doesn't really require anything special then basic logic with timers.
Depends how precise you need the timing to be.
In RSLogix you can put the code in a Periodic Task with a higher processor priority so that
processor load does not affect the execution timing.