Having covered the fundamentals to stepping motors and drive systems, this second and final part provides a comprehensive design to a fourchannel unipolar stepper drive with complete interface electronics for direct operation from a standard PC.This second part of the article includes full details to build, test and use a low-cost 4-channel stepper motor drive which can be tailored to your applications. The project includes the RS-232 interface for direct connection to the PC, a custom high-level control language for executing commands sent to the controller and the drive electronics to power the motors. In addition, the PC communication software will be explained in some detail allowing full customisation to your specific requirements. This software is compatible with all Microsoft Windows 32-bit platforms and was developed in Borland Delphi.