Hybrid pin control using boundary-scan and its applications

Boundary-Scan (B-S) has been widely used for interconnect testing. It allows all pins of a B-S chip to be controlled uniformly by either system or B-S logic. The requirement that all pins are controlled by the same logic limits B-S usage for many applications. We propose a new B-S instruction, called PINCONTROL, to allow mixed control of chip pins. That is, each pin can be individually configured to be controlled by the system or B-S logic. In this paper we shall demonstrate the application of this instruction for fault injection and inter-chip path delay testing.