Validation REquired for Checks

Hi, i have to write validation for FCH5 (manual check). This is because SAP allows to post a check for any house bank and account id.

I have a logic for it. But i do not know how to write validation. Its a new thing for me. Its will be of great help if anyone send the material on writing validation. You can send it on details mentioned in my profile

Edited by: Deepak Agrawal on Oct 5, 2009 6:20 PM