JTAG System Test in a MicroTCA World

The telecommunicatoins industry has developed new system architectures through the PICMG organization. These are the Advanced Telecom Computing Architecture (ATCA) platforms that consist of the ATCA, ATCA200, Advanced Mezzanine Card (AMC) and MicroCTA specifications. Unfortunately, only the AMC and MicroCTA specification directly addresses testability using a JTAG interface. This paper will address the system test facility specified in the MicroCTA specification for testing the incorporated AMC modules as well as the MicroTCA Carrier Hub (MCH) controllers. Access to the individual AMC JTAG chains is provided using a JTAG Switch Module that provides a programmable star architecture in the system.