Step7 cpu clock

How do i monitor the CPU clock in ladder program. I want to reset a whole lot of product data at the end of the each shift. So i would like ot set a bit at 6am and 6pm of each day. Any help is appreciated.

Here's a recent example that generates one-shots at pre-defined shift times. You can easily modify it to set bits instead of generating one-shots.

http://www.plctalk.net/qanda/showthread.php?t=51248

Thanks it works great. Now a different question.
Is there a way to sync the cpu time with Wincc pc time automatically. This will help to keep the correct time in the cpu with day light saving time.
Thanks