Software/hardware integration on microprocessors Time saved by parallel separate development of hardware and software for a given application is often lost when it comes to marrying the two components -- but adequate training can prevent this, says Jonathan Bowen Hardware and software are often designed separately and in parallel to speed up the design stage. A microprocessor-based project is described which demonstrates some examples of the possible pitfalls during the integration of these two components. Partici- pants in the project are also introduced to the advanced development equipment which should be used for this purpose. The experiences of a group of postgraduate students who initially undertook the project are described. microsystems system integration development syslems Because of time constraints, various aspects of industrial development work are often carried out in parallel. In microprocessor-based systems, an obvious breakdown of tasks is that between the production of software and hardware. However, when these components are produced separately many difficulties can arise when they are integrated into a complete product. For instance part of the system may have been incompletely or incorrectly specified. The purpose of the project described in this paper is to illustrate some of these problems and also to allow hands-on experience of the sophisticated equipment needed for this purpose. The project was developed as part of an intensive one-week UK Science and Engineering Research Council vacation course on robot technology for postgraduate students. Owing to the short timescale of the project, a relatively simple product was designed and partially implemented for the participants. The hardware was completely designed apart from the choice of divider Oxford University ComputingLaboratory, 8-11 KebleRoad,Oxford OX1 3QD, UK Jonathan Bowen is a member of the Program- ming Research Group at the Computing Laboratory of Oxford University, UK. Until the end of 1984 he was a research assistant at Imperial College of Science and Technology, London, UK, where he acted as adviser to college members wishing to develop micro- processor-based systems for their research. His own research interests include microprocessor and microcomputer applications, computer graphics and distributed computing. for the timing interrupt generator. One or two unexpected 'features' were also included. Some of these are described below. A working version of the software was developed to prove that it could be done. However, the group was only given skeleton versions of software modules to be implemented by them. Any modules which they could not complete because of lack of time or personnel could be supplied to be integrated with their software. As it turned out, this was not necessary to produce a working system. HAR DWAR E The project was chosen to be simple enough to be implemented in the short time available, but interesting 0141-9331/85/01008-07 $03.00 © 1985 Butterworth & Co. (Publishers) Ltd 8 microprocessors and microsystems