Broadcast-based minimization of the overall access time for the IEEE 1687 network

摘要

The IEEE Std. 1687 enables flexible access to on-chip instruments through the JTAG test-access port. This flexibility enables the minimization of the overall access time (OAT), and a number of techniques have been proposed to achieve this goal. However, these techniques do not utilize the broadcast feature in the 1687 network. In order to further reduce the OAT, we present an efficient test-scheduling method that exploits the broadcast feature for instrument access. Two optimization solutions are then proposed - the first solution minimizes the OAT without the retargeting time, while the second one reorders the configurations so as to minimize the overall retargeting time among configurations. Three industry test cases are used to evaluate the effectiveness of the proposed method.