An arithmetic oriented multiprocessor system for industrial measurements

Abstract

The system is intended to perform the local data acquisition and data processing works at a pipeline measuring station. The data acquisition part receives commonly used industrial 4–20 mA current loops, performs relatively slow quad slope A/D conversion with high common voltage and normal mode rejection to four BCD digits precision. The arithmetic processor is a cheap, calculator-like device, running to its own ROM. Each calculation subroutine is initiated by the 8085 master processor. Data exchange goes by means of a dual port CMOS RAM. Ease of software generation, even for complex calculations containing transcendental functions is emphasised. For man-machine interface convenience, BCD coding is maintained from data entry to display results.