The N-S diagrams combine the structures of programming language or the pseudocode with graphic representations that facilitate visual perception, like flow diagrams. In spite of anterior, this technique is little used, maybe because the tools for design and to prove this type of diagrams are scarce. This article presents tool ICD-Chapin, a command interpreter for N-S diagrams, this program permits to construct, edit, review and execute N-S diagrams and generates code for C and Java language. This tool was developed with free software license, using object oriented methodology and under unified process of development.