NATO STANAG 7142

Abstract

<b><u>Scope:</u></b> <span id="LabelScope"> <br> The VMEbus specification defines an interfacing system used to interconnect microprocessors, data storage and peripheral control devices in a closely coupled hardware configuration. The aim of the agreement is to standardize on an already developed and accepted commercial standard microprocessor backplane bus for the following reasons: <br> a. To provide a common bus architecture that will support computing-intensive functions such as avionics systems. <br> b. To provide a wide procurement base for future systems supported by the provision of commercially produced hardware during the development stage. <br> c. To facilitate a higher degree of component commonality thus reducing costs (larger user base), whilst increasing component interchangeability. <br> d. Machine-based constraints such as addressing modes, word lengths, support software and languages will be obviated to some degree when considering interoperability. <br> e. To allow communication between devices on the VMEbus without disturbing the internal activities of other devices interfaced to the VMEbus. <br> f. To specify the electrical, mechanical system characteristics and protocols required to design devices that will reliably and unambiguously communicate with other devices interfaced to the VMEbus. <br> g. To allow a broad range of design latitude so that the designer can optimize cost and/or performance without affecting system compatibility.