Navigating test access in systems

Abstract

Hierarchical navigation modes should allow for: (1) a simple busing structure capable of dynamically routing an 1149.1 test bus within any system hierarchy, (2) a protocol, transparent to 1149.1, capable of directing the routing process and confirming the connection made, (3) a method of transmitting 1149.1 test patterns through a routed connection without having to reformat or translate the patterns, and (4) a method of executing data transfer operations through a routed connection transparent to 1149. 1. It is important to note that only one of the three test access methods can provide these hierarchical navigation features, Hierarchical ASP (HASP)C41.