Chapter 3 Creating and Editing Programs | DOP-EXIO Series 5. Click the icon to compile the ladder diagram and convert it to instruction codes. After compiler action is completed, the numbers of steps will show on the left-hand side of the start of the ladder diagram. 6. If the ladder diagram is not correct, an error message dialog box will appear and point out the exact erroneous rows and addresses after the compiler action is completed. 3-4 Revision March, 2008, Doc. Name: 2007PDD23000014