it is about cp243-2 as-interface module

well, this is not that tough... What you need besides your S7-200 and the CP 243-2 is:

- a AS-i Power Supply,
- AS-i Cable, the yellow one, and
- your AS-i Slaves.

In some cases, especially if you have AS-i Slaves that have to be treated a certain way to set the AS-i Address to them you may need a AS-i Addressing device.

First you have to wire up all devices with the yellow Cable, you may have to care about the Connectors used, but this depends on the Slave you use.
Thanyou have to set the Address within the AS-i Bus to each Slave you use. This is done the easiest way by using the Addressing device I was writing about.
Now you can switch the Master to on. The Master has to be taught which I/O Slaves he has and as soon as he runs in the Protected Mode the Master System is on. The Access to the single Slave I/O is done within the PLC Program... that's it... I guess.

Have fun.

Best regards