Abstract This paper discusses a method for developing efficient and portable software for 8‐bit microprocessors used in real‐time applications. The technique used is to design an ‘intermediate level language’ (ILL) which defines low‐level primitives to support the real‐time application programming and the constructs of high level languages. Thus, the high level language (HLL) program goes through two stages of translation; first to the ILL code and then to the machine code of a microprocessor. The ILL instruction set developed bridges the gap between high level languages and the poor instruction set of microprocessors. This allows the development of optimized and portable code for the microprocessors. The ILL operations, data types, data organization, control structures, synchronization, communication and multi‐tasking facilities are described. The effectiveness of this technique is shown by comparing the code generated by the ILL approach with the code available for a sample real‐time application written directly in assembly level language.

The design and operation of a simple two-input arbiter module suitable for implementing n-input arbiter trees are given in this correspondence.