Applilet EZ PL is a programming software that can create microcontroller application software easily in a manner similar to solving a puzzle, without using any programming language. This software allows even users who are unfamiliar with programming languages and do not have knowledge of software development to easily create a variety of microcontroller application software using a graphical user interface (GUI) on a host machine. Applilet EZ PL can also be used to study and evaluate the basic operation of a system that uses a microcontroller.